The Cleanroom Wiki: Terms and definitions
Welcome to the Cleanroom Wiki, the wiki for terms related to cleanroom technology.
This service of COLANDIS GmbH was created to provide companies from the industry and technology sector with a central contact point for the technical area in cleanroom technology.
We will regularly explain new terms related to cleanroom, cleanliness suitability and cleanroom suitability. Have fun browsing, looking up and informing.
Cleanroom technology terms from A to E
Absorption
Transfer of infrared energy to the molecules present within the pathway of the radiation. (ECSS-Q-ST-70-05C, 2009)
The incorporation of one substance into another. (VDI 2083: Blatt 9.2: 2009-07 Düsseldorf)
acceptance test (acceptance, qualification)
qualitative and quantitative verification of the specified parameters and/or acceptance criteria of an ME at the intended place of use prior to commissioning (VDI 2083: Blatt 16.2: 2021-04 Düsseldorf)
ACC filter
Device dedicated to the removal of gaseous (molecular) contamination from the air.
Note 1: Its functioning is based on physical or chemical mechanisms.
Note 2: The following terms are also common: adsorber, molecular filter, gas-phase filter, chemical filter.
(VDI 2083: Blatt 8.1: 2014-10 Düsseldorf)
Acid
Species whose chemical reaction characteristic is to establish new bonds by the acceptance of electron pairs (ISO 14644-8: 2003-09)
Substance whose chemical reaction characteristic is to establish new bonds by the acceptance of electron pairs. (VDI 2083: Blatt 17: 2013-06 Düsseldorf)
Acid capacity (KS)
Quantity of hydrogen ions (H3O+) that a certain volume of water can accommodate until reaching a predefined of water can accommodate until reaching a predefined pH-value. In water, this is primarily the effect of hydrogen-carbonate and carbonate ions. With regard to the titration curve of carbonic acid, the final pH-values are specified to be 8,2 and 4,3: acid capacity up to pH-value 8,2 (KS8,2), acid capacity up to pH-value 4,3 (KS4,3; formerly carbonate hardness or m-value). (as defined in DIN 4046)
Note: Obsolete term: m-value
(VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Action level
Level set by the user in the context of controlled environments, which, when exceeded, requires immediate intervention, including the investigation of cause, and corrective action. (EN ISO 14644-7) (VDI 2083: Blatt 3.1: 2012-06 Düsseldorf)
Active minienvironment
A minienvironment that creates and maintains a controlled condition. (SEMI E44-96, Guide for Procurement and acceptance of minienvironments, 1995)
ME which creates special process conditions by active ventilation through HEPA and/or AMC filters or by means of an inert gas flow (VDI 2083: Blatt 16.2: 2021-04 Düsseldorf)
Active surface
Surface area in contact with the air in a cleanroom (VDI 2083: Blatt 9.2: 2017-01 Düsseldorf)
Activity
Effective concentration of atoms, ions and molecules. It is the measure of concentration to be entered in the laws derived for ideal mixtures and solutions (such as the law of mass action) so that they can even be applied when the behaviour in the respective system is no longer ideal. It is expressed in terms of the activity coefficient. (VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Adapted minienvironment
A minienvironment which can be removed from the process tool without restricting the tool’s wafer loading/unloading and processing functions. Tools may have provisions for input/output interface, power and interlock communications. (SEMI E44-96, Guide for Procurement and acceptance of minienvironments, 1995)
ME which is not permanently connected to the production facility, which is thus removable, and which can (but does not necessarily) contain components for the supply of conditioned air (VDI 2083: Blatt 16.2: 2021-04 Düsseldorf)
Adapted SMIF
A unit including a SMIF port and a cassette transfer mechanism. The unit can be removed from the process tool without restricting the tool’s loading/unloading function. (SEMI E44-96, Guide for Procurement and acceptance of minienvironments, 1995)
Adsorption
The process of adhesion of an atom or molecule from the gas or liquid phase onto a solid surface.
Note: The reverse process is desorption.
(VDI 2083: Blatt 9.2: 2009-07 Düsseldorf)
Aerobe
Organism only viable in the absence of oxygen. (Introduction to Contamination Control and Cleanroom Technology, 1999)
Aerosole
A colloidal system in which the dispersion medium is a gas, i.e. a liquid solution which has been atomized into a fine mist (small droplets). (Introduction to Contamination Control and Cleanroom Technology, 1999)
Agar
A dried substance of algar origin having the property of melting at 100°C and solidifying into a gel at 40°C . Agar is not normally digested by most bacteria and is used as a medium in the preparation of solid cultures of microorganisms. (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Airborne contamination
Within this Guideline it is understood that contamination of the air is due to particles. (VDI 2083: Blatt 2: 1996-02 Düsseldorf)
Airborne molecular contamination (AMC)
Presence in the atmosphere of a cleanroom or controlled environment of molecular (chemical, non-particulate) species in the gaseous or vapour state, which may have a deleterious effect on the product, process or equipment in the cleanroom or controlled environment
NOTE. This definition does not include biomolecules, which are judged to be particulates.
(ISO 14644-8: 2003-09)
Airborne particulate cleanliness class
The level of cleanliness specified by the maximum allowable number of particles per cubic meter of air (per cubic foot of air), shown for the class in Table 1, as determined by the statistical methods of 5.4. The name of class in SI units is taken from the logarithm (base 10) of the maximum allowable number of particles, 0.5µm and larger, per cubic meter. The name of the class in English (U.S. customary) units is taken from the maximum allowable number of particles, 0.5µm and larger, per cubic foot. (Federal Standard FED-STD-209E / 11. September 1992; airborne particulate cleanless classes in cleanrooms and clean zones)
Air changes
A value indicating the number of times per hour that the air is changed within a certain room or containment. A very commonly used indicator for conventional cleanroom that purge themselves. (Introduction to Contamination Control and Cleanroom Technology, 1999)
Airlock
Intermediate room that is normally ventilated. (Introduction to Contamination Control and Cleanroom Technology, 1999)
Intermediate room that is normally ventilated, and used to minimize the transfer of airborne contaminants from one area to another (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Air / gas supply
A method to create a clear air/ gas environment in the minienvironment. (SEMI E44-96, Guide for Procurement and acceptance of minienvironments, 1995)
Air velocity
A value indicating the speed of the air movement in a room. A very commonly used indicator of the ability of a unidirectional-flow cleanroom that purge itself. (Introduction to Contamination Control and Cleanroom Technology, 1999)
A value indicating the speed of the air movement in a room or a zone in the room. A very commonly used indicator of the ability of a unidirectional-flow cleanroom that purge itself. (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Alcohol
Any of a class of organic substance formed from hydrocarbons by the substitution of one or more hydrogen atoms with en equal number of hydroxyl groups. Alcohols are mainly used as cleaning agents because they can solubilize fats and are potent disinfectants where microorganisms are concerned (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Alert level
Level set by the user in the context of controlled environments, giving early warning of a drift from normal conditions, which, when exceeded, should result in increased attention to the process. (EN ISO 14644-7) (VDI 2083: Blatt 3.1: 2012-06 Düsseldorf)
Alga
Any individual species of algae. (Introduction to Contamination Control and Cleanroom Technology, 1999)
Algae
A group of cryptogamic plants in which the body is unicellular. This group includes seaweeds and many unicellular fresh water plants, most of which contain chlorophyll. (Introduction to Contamination Control and Cleanroom Technology, 1999)
Alkali
A class of chemicals which from soluble soaps with acids and also form soluble carbonates. These substances are mainly used as cleaning agents due to their ability to dissolve proteins and other organic, material (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Alkalinity
Acid consumption by water.
Note: See also acid capacity, base capacity.
(VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Alternative test method
Test method for verifying the same characteristic, proven to return results identical to those obtained using the preferred method.
(VDI 2083: Blatt 18: 2012-01 Düsseldorf)
AMC (airborne molecular contamination)
The occurrence of such molecular (chemical, nonparticulate) substances in the gas or vapour phase, within the atmosphere of a cleanroom or controlled environment, as can have a detrimental effect on the product, the process, the equipment or the personnel.
Note: The classification of a substance as AMC is application-specific; this means that the same substance may, or may not, in different applications, be classified as a contamination.
(VDI 2083: Blatt 9.2: 2009-07 Düsseldorf)
Presence in the atmosphere of a cleanroom or controlled environment of molecular gases or vapours that may have a deleterious effect on humans, the product, process, environment or equipment (adapted from DIN EN ISO 14644-6, 2.12)
Note 1: This definition does not include macromolecules of biological origin, which are judged to be particles [adapted from DIN EN ISO 14 644-6].
Note 2: The AMC classification varies from case to case. Hence, the same substance can be classified or not as a contaminant in different cases (compatibility with the required cleanliness).
According to current standards, “AMC” is no longer used for classifying cleanliness. For this purpose, the airborne cleanliness by chemicals (ACC) as per DIN EN ISO 14 644-8 shall be used.
(VDI 2083: Blatt 9.2: 2017-01 Düsseldorf)
AMC filter
Device dedicated to the removal of gaseous (molecular) contamination from the air. Its functioning is based on physical or chemical mechanisms.
Note: The following terms are also common: adsorber, molecular filter, gas-phase filter, chemical filter.
(VDI 2083: Blatt 9.2: 2009-07 Düsseldorf)
Anaerobic
Lacking molecular oxygen (Introduction to Contamination Control and Cleanroom Technology, 1999)
Anaerobic microorganisms
Microorganisms that have the ability to grow in the complete or almost complete absence of molecular oxygen. (Introduction to Contamination Control and Cleanroom Technology, 1999)
Anderson sampler
Sampling device for the collection of microorganisms based on impaction. The sampler has up to eight stages stacked in series, each stage consisting of a perforated plate. A Petri dish of agar growth medium is placed beneath each plate. Air that is draw into the sampler impacts with the agar of each stage. Air velocity increases at each succeeding stage due to progressively smaller holes causing suspended particles to be distributed among the plates according to size. Larger particles are trapped in the upper stages; smaller particles in the lower stages (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Anisokinetic sampling
The condition of sampling in which the mean velocity of the flowing air stream differs from the mean velocity of the air entering the inlet sampling probe. Because of particle inertia, anisokinetic sampling can cause the concentration of particles in the sample to differ from the concentration of particles in the air being sampled. (Federal Standard FED-STD-209E / 11. September 1992; airborne particulate cleanless classes in cleanrooms and clean zones)
The taking of air samples under conditions in which the velocity and direction of the air entering the sampler are different from the velocity and direction of the air in the room (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Antiseptic
A substance that will inhibit the growth and development of microorganisms without necessarily destroying them. (Introduction to Contamination Control and Cleanroom Technology, 1999)
Antisepsis
The prevention of sepsis by the inhibition or destruction of the causative organisms. (Introduction to Contamination Control and Cleanroom Technology, 1999)
Antistatic
Property of a material having little tendency to electrostatic charging
Note: The limits listed in this standard (resistance, charge, etc.) are but examples and have to be agreed upon between user and supplier for the object in question. For instance, even electrostatic potentials below 10 V can damage or destroy electronic components.
Antistatic material
Material with little tendency to accumulate electrostatic charge, i.e. the material allows no, or only little, electrostatic charging (3.4) to occur. (VDI 2083: Blatt 17: 2013-06 Düsseldorf)
Antistatic properties
The capability to reduce electrostatic charges on the surfaces of the workplace or the product, either to a specified level or to the nominal value, by means of conduction or other mechanism. (VDI 2083: Blatt 9.1: 2006-12 Düsseldorf)
As-built cleanroom (facility)
A cleanroom (facility) that is complete and ready for operation, with all services connected and functional, but without equipment or operating personnel in the facility. (Federal Standard, Stuttgart 1991)
Condition where the installation is complete with all services connected and functioning but with no production equipment, materials, or personnel present (ISO 14644-1:1999 (E))
Aseptic
Free from infection or septic material. (Introduction to Contamination Control and Cleanroom Technology, 1999)
Aseptic filling
Sterile containers are filled with the sterile product and sealed with sterile closures. Frequently used with products that cannot be sterilized at the final stage of production (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Aseptic technique
Techniques that are carried out to avoid infection. In other words aseptic techniques are used to prevent sterile material and/or products from becoming infected. (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Associated controlled environment
Clean area surrounding the core area (see also VDI 2083 Part 4.1). (VDI 2083: Blatt 9.1: 2006-12 Düsseldorf)
ASTM
American Society for Testing and Materials (ECSS-Q-ST-70-05C, 2009)
ATR
Attenuated total reflection (ECSS-Q-ST-70-05C, 2009)
At-rest cleanroom (facility)
A cleanroom (facility) that is complete, with all services functioning and with equipment installed and operable or operating, as specified, but without operating personnel in the facility. (Federal Standard, Stuttgart 1991)
Condition where the installation is complete with equipment installed and operating in a manner agreed upon by the customer and supplier, but with no personnel present (ISO 14644-1:1999 (E))
Attenuated total reflection
Reflection that occurs when an absorbing coupling mechanism acts in the process of total internal reflection to make the reflectance less than unity. (ECSS-Q-ST-70-05C, 2009)
AU
Absorbance Unit (ECSS-Q-ST-70-05C, 2009)
Audit
Systematic, independent and documented process for obtaining audit evidence and evaluating it objectively to determine the extent to which audit criteria fulfilled. [ISO 9000: 2000] (VDI 2083: Blatt 11: 2008-01 Düsseldorf)
Auditor
person with the competence to conduct an audit (International Standard, ISO/FDIS 14001, 2004)
Autoclave
An apparatus for effecting sterilization by steam under pressure, fitted with a gauge that automatically regulates the pressure and therefore the degree of heat to which the contents are subjected (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Background
Outgassing rate of the vacuum chamber under normal conditions of operation at a certain mass range and time in the absence of the part to be verified. (ASML-Standards, Cleanliness Grades, Grade 2: Verification RGA, GSA 07 2211,2008)
Background noise
Within the context of this guideline, background noise is the concentration of particles introduced into the test environment by the air-conditioning system. (VDI 2083: Blatt 8: 2002-09 Düsseldorf)
Bacteria
Main group of microorganisms. (Introduction to Contamination Control and Cleanroom Technology, 1999)
Bacterial
Capable of killing vegetative bacterial cells, but not necessarily bacterial spores (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Bacteriostat
An agent that inhibits the growth of bacteria (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Bacteriostatic
An agent that inhibits the growth or multiplication of bacteria (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Barrier class
The barrier classes are based on the protective effect to be afforded by the clean environment. Depending on the application, they are either
-person-related,
-product-related,
-environment-related or
-combinations of the above,
see also OEL value.
(VDI 2083: Blatt 16.1: 2010-08 Düsseldorf)
Base
Species whose chemical reaction characteristic is to establish new bonds by the donation of electron pairs (ISO 14644-8: 2003-09)
Substance whose chemical reaction characteristic is to establish new bonds by the donation of electron pairs. (VDI 2083: Blatt 17: 2013-06 Düsseldorf)
Base capacity (KB)
Quality of hydroxide ions (HO–) that a certain volume of water can accommodate until reaching a predefined pH-value. The final pH-values defined are the same as for the acid capacity:
base capacity up to pH-value 8,2 (KB8,2); formerly “free carbonic acid”), base capacity up to pH-value 4,3 (KB4,3, formerly negative m-value). (as defined in DIN 4046)
Note: Obsolete term: p-value
(VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Base noise
Particle concentration which is brought into the test environment by the air-handling system. (VDI 2083: Blatt 9.1: 2006-12 Düsseldorf)
Bioaerosol
Finely dispersed biological agents in a gaseous environment. (VDI 2083: Blatt 18: 2012-01 Düsseldorf)
Biocide
An agent that kills organisms (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Biocontamination (biological contamination)
Biocontaminations may be particulate (bacteria, viruses, etc.) or molecular (endotoxins, etc.).
Note: In the context of this guideline, medical or specific characteristics of biocontamination are not addressed unless these characteristics concern matters of general product protection/personal protection. Also, the guideline only deals with such characteristics as concern the respective categories, rather than considering characteristics of specific biological entities, provided this is not required for assessing the hazard potential (see also VDI 2083 Part 18)
(VDI 2083: Blatt 16.1: 2010-08 Düsseldorf)
Contamination of raw materials, equipment, personnel, surfaces, liquids, gases or air with viable particles. (VDI 2083: Blatt 18: 2012-01 Düsseldorf)
Biofilm (bacterial lawn)
Film-like growth of microorganisms held together by a matrix of extracellular polymeric substances (EPS). Biofilms form primarily in the aqueous phase. They can form and grow at any aqueous-phase interface. (VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Biofouling (biological fouling)
Deposits on surfaces due to microbial growth (bacteria, algae, moulds) and to biofilm formation. May lead to corrosion and material damage.
Note: See also fouling of membranes (Section 3.3) and fouling of ion exchangers (Section 3.4).
(VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Biological agents
Microorganisms, including those which have been genetically modified, cell cultures and human endoparasites which may be able to provoke any infection, allergy or toxicity.
(in accordance with the Council Directive 90/679/EEC)
(VDI 2083: Blatt 12: 2000-01 Düsseldorf)
Biomonitoring
Measurements for monitoring biocontamination, carid out either continuously or at regular intervals. (VDI 2083: Blatt 18: 2012-01 Düsseldorf)
Biosafety cabinet
Contaminate device for protection of operations and workers from hazardous microorganisms and in some cases for protecting the work area from contaminants from the outer environment (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Biotoxic
Contaminant species that is obnoxious to the development and preservation of the life of organisms, microorganisms, tissues or individual cells (ISO 14644-8: 2003-09)
Breakthrough
breakthrough = 100% – separation efficiency
Note: The breakthrough is expressed as a percentage.
(VDI 2083: Blatt 9.2: 2009-07 Düsseldorf)
Buffer intensity (PI)
Sensitivity of a solution towards an added acid or base.
Note: The buffer intensity is used to assess the corrosiveness of water.
(VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Calibration
Comparison of a measurement standard or instrument of unknown accuracy (Federal Standard, Stuttgart 1991)
Determination of the accuracy of an invariation from a standard, to a certain necessary correction factor. (Introduction to Contamination Control and Cleanroom Technology, 1999)
Comparison of a measurement standard or instrument of unknow accuracy with another standard or instrument of know accuracy to detect, correlate, report, or eliminate by adjustment any variation in the accuracy of the unknown standard or instrument. (Federal Standard FED-STD-209E / 11. September 1992; airborne particulate cleanless classes in cleanrooms and clean zones)
Capacity
The mass of a specific substance (AMC) taken up by a filter before a specified breakthrough occurs.
Note 1: The capacity is a characteristic of AMC filters which depends on the concentration and the operating conditions.
Note 2: The total capacity is the mass of a specific substance (AMC) for 100% breakthrough.
(VDI 2083: Blatt 9.2: 2009-07 Düsseldorf)
Carbonate hardness (temporary hardness)
Hydrogen-carbonate (HCO3-) concentration not exceeding the total hardness. (VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
CCP
Critical Control Point (Introduction to Contamination Control and Cleanroom Technology, 1999)
CDA
Clean dry air (SEMI F28-1103, test method for measuring particle generation from process panels, 2003)
Centrifugal air sampler
A sampling device used for the collection of microorganisms suspended in air, based on impaction. The impaction force is obtained with a rotating fan which forces particles in the onto an agar plate (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
CFU
Colony Forming Unit (Introduction to Contamination Control and Cleanroom Technology, 1999)
cGMP
Current Good Manufacturing Practice (Introduction to Contamination Control and Cleanroom Technology, 1999)
Changing room
Room where people using a cleanroom may change into or out of cleanroom clothing. (Introduction to Contamination Control and Cleanroom Technology, 1999)
Room where people using a cleanroom may change into, or out of, cleanroom apparel (ISO 14644-4:2001 (E))
Chemical contamination
(molecular contamination)
Undesirable perceivable molecular modification of substances and their contamination or degradation, caused by contaminations, regardless of the contamination path (e.g. from the gas phase, as a particle, as a germ).
(VDI 2083: Blatt 8.1: 2014-10 Düsseldorf)
Undesirable and perceptible chemical change, or contamination (3.1) or destruction, of substances caused by contaminants (3.4), regardless of how the contamination is carried in (from the gaseous phase, as a particle (3.2) or germ, etc.). (VDI 2083: Blatt 17: 2013-06 Düsseldorf)
Chemical-mechanical polishing (CMP)
Planarization of structures on a wafer surface by the action of mechanical forces and simultaneous chemical action of the oxidant.
Note: The process uses polishing slurries and abrasives.
(VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Chemical resistance
Resistance to the effects of chemicals (e.g. cleaning agents and disinfectants)
Note 1: The outer appearance can change.
Note 2: “Chemical resistance” is not to be mistaken in this case for the PPE requirements regarding chemical protection.
(VDI 2083: Blatt 9.2: 2017-01 Düsseldorf)
Chemical resistance generally describes the durability of materials (3.1) under the influence of chemicals/substances (such as cleaning agents and disinfectants).
Note 1: Changes in appearance of material are possible.
Note 2: An aspect of chemical resistance referring to matals is corrosion (3.6).
(VDI 2083: Blatt 17: 2013-06 Düsseldorf)
Chemisorption
The removal of specific substances (here: ->AMC) by way of physical adsorption and subsequent chemical reaction. The chemical reaction is, as a rule effected by a reactive agent with which the adsorbent has been impregnated (cf. ->physiorption).
Note: Unlike physisorption, chemisorption is mostly irreversible.
(VDI 2083: Blatt 9.2: 2009-07 Düsseldorf)
Classification
Level (or the process of specifying or determining the level) of airborne particulate cleanliness applicable to a cleanroom or clean zone, expressed in terms of an ISO Class N, which represents maximum allowable concentrations (in particles per cubic metre of air) for considered sizes of particles
NOTE 1 The concentrations are determined by using equation (1)
NOTE 2 Classification in accordance with this International Standard is limited to the range extending from ISO Class 1 through ISO Class 9.
NOTE 3 The considered particle sizes (lower threshold values) applicable for classification in accordance with this International Standard are limited to the range from 0,1 µm through 5 µm. Air cleanliness may be described and specified (but not classified) in terms of U descriptors or M descriptors (see 2.3.1 or 2.3.2) for considered threshold particle sizes that are outside of the range covered by classification.
NOTE 4 Intermediate ISO classification numbers may be specified, with 0,1 the smallest permitted increment; i.e., the range of intermediate ISO classes extends from ISO Class 1,1 through ISO Class 8,9.
NOTE 5 Classification may be specified or accomplished in any of three occupancy states
(ISO 14644-1:1999 (E))
Distinction of classes of air cleanliness by defining limits. The limit of a class is the maximum permissible particle concentration for a specified particle size (VDI 2083: Blatt 1: 2003-06 Düsseldorf)
Distinction of airborne particulate cleanliness according to class limits. The class limit is the maximum permissible particle concentration at a specified particle size (VDI 2083 Part 1). (VDI 2083: Blatt 9.1: 2006-12 Düsseldorf)
Rating of the particle emission from materials (3.1) under frictional load based on nationally and internationally established air cleanliness classes (such as VDI 2083 Part 1, DIN EN ISO 14644-1). (VDI 2083: Blatt 17: 2013-06 Düsseldorf)
Cleanability
Degree to which a cleaning (3.5) on contaminated surface (3.5) is possible using appropriate cleaning methods and agents. (VDI 2083: Blatt 17: 2013-06 Düsseldorf)
Clean air device
Stand-alone equipment for treating and distributing clean air to achieve defined environmental conditions (ISO 14644-4:2001 (E))
Clean area(s)
Zones in which the concentration of airborne particles is controlled to meet a specified cleanless class according to part 1 of this Guideline. (VDI 2083: Blatt 4: 1996 Düsseldorf)
Area within a room, an installation, or a machine, where the condition are specified as for a cleanroom, and which may be enclosed by a further area (VDI 2083: Blatt 1: 2003-06 Düsseldorf)
Clean environment
Clean area adjacent to the critical area. This includes material locks and personal locks connected to the clean environment. (VDI 2083: Blatt 4: 1996 Düsseldorf)
Cleaning
Removal of contamination (ASML-Standards, Cleanliness Grades Grade 2: Surface Cleanliness, GSA 07 2310, 2007)
Cleaning for the purpose of this Guideline is the removal of particulate contamination affecting product or process. (VDI 2083: Blatt 4: 1996 Düsseldorf)
For the purposes of this guideline, the term “cleaning” denotes the targeted removal of particulate contaminations affecting the product or the process. (VDI 2083: Blatt 9.1: 2006-12 Düsseldorf)
Targeted removal of contaminants from a surface (ISO 14698-3). (VDI 2083: Blatt 5.1: 2007-09 Düsseldorf)
Cleaning is the targeted removal of visible particle and other contamination.
Note: The effectiveness is assassed visually, using optical means, if required. This assessment is qualitative.
(VDI 2083: Blatt 16.1: 2010-08 Düsseldorf)
targeted reduction of impurities to a defined level
Note: Effectiveness is established according to specified procedures. As a rule, these are qualitative procedures.
(VDI 2083: Blatt 16.2: 2021-04 Düsseldorf)
Dedicated removal of contaminations (3.1) interfering with the product or the process. (VDI 2083: Blatt 17: 2013-06 Düsseldorf)
Removal of contamination from an area or an object to the extent required for further processing and for the intended use. (VDI 2083: Blatt 18: 2012-01 Düsseldorf)
Cleanliness
Condition of a product, surface, device, gas, fluid, etc. with a defined level of contamination
NOTE Contamination can be particulate, non-particulate, biological, molecular or of other consistency.
(ISO 14644-4:2001 (E))
Air cleanliness at the work place is particulate cleanliness, i.e. the absence of disturbing airborne contamination (particles) which appear as dust, mist or microorganisms. The measure of this cleanliness is the particulate concentration per volume unit.
Non-particulate cleanliness of gases and ions (electrical fields) has be differentiated from this.
(VDI 2083: Blatt 2: 1996-02 Düsseldorf)
Cleanliness chain
The term “cleanliness chain” subsumes the entirety of all conditions to be met and all measures to be taken and their interactions. (VDI 2083: Blatt 11: 2008-01 Düsseldorf)
Cleanliness grade
Established level of cleanliness in a given volume, or a given surface. (ASML-Standards, Cleanliness Grades Grade 2: Surface Cleanliness, GSA 07 2310, 2007)
Cleanliness level
An established maximum allowable amount of contamination in a given area or volume, or on a component. (Military Standard Product Cleanliness Levels and Contamination Control Program MIL-STD-1246C, 11. April 1994)
Cleanliness suitability
Cleanliness suitability tests on operation materials are concerned with all contamination factors (see Annex A). Product-specific cleanliness requirements form the basis for assessing form the basis for assessing the cleanliness suitability of an operating material.
(VDI 2083: Blatt 8: 2000-08 E; Düsseldorf)
Cleanliness suitability tests on operation materials are concerned with all contamination factors Product-specific cleanliness requirements form the basis for assessing form the basis for assessing the cleanliness suitability of an operating material.
(VDI 2083: Blatt 8: 2002-09 Düsseldorf)
Cleanliness verification
Checking the required cleanliness level. (ASML-Standards, Cleanliness Grades Grade 2: Surface Cleanliness, GSA 07 2310, 2007)
Cleanroom
A room in which the concentration of airborne particles is controlled and which contains one or more clean zones. (Federal Standard, Stuttgart 1991)
Room in which the concentration of airborne particles is controlled, and which is constructed and used in a manner to minimize the introduction, generation, and retention of particles inside the room, and in which other relevant parameters, e.g. temperature, humidity, and pressure, are controlled as necessary (ISO 14644-1:1999 (E))
Room with a defined concentration of airborne particles, so designed and used as to minimise the number of particles carried into, or generated in, the room, and deposited in the room, and where other parameters relevant to cleanliness, such as temperature, humidity, and pressure are controlled as required (VDI 2083: Blatt 1: 2003-06 Düsseldorf)
Room in which a specified limit for the concentration of airborne, and other forms of, contamination is observed.
Note: A controlled environment may be open or enclosed and may lie within or outside of a cleanroom.
(VDI 2083: Blatt 4.1: 2006-10 Düsseldorf)
A room in which the concentration of airborne particles is controlled to a certain level. Control of cleanliness in such a room in often achieved by controlling the introduction, formation and retention of particles in the room. In many cases there is also a need to control temperature, pressure and humidity (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Cleanroom compatibility
Cleanroom compatibility serves to assess the suitability of a piece of equipment for use in cleanrooms specified in accordance with a technical rule for assessing the air cleanliness. For the purposes of this guideline, the classification is based on the particle emission. (VDI 2083: Blatt 9.1: 2006-12 Düsseldorf)
criterion for the assessment of the suitability of a piece of equipment for use in cleanrooms specified in accordance with technical in rule for assessing the air cleanliness
Note 1: For the purposes of this standard, the classification is based on the particle emission.
Note 2: Cleanroom compatibility is included in the compatibility with the required cleanliness.
(VDI 2083: Blatt 9.1: 2021-01 Düsseldorf)
Evaluation of consumables in terms of the compatibility with cleanrooms based on the release of particulate contaminants Note: Cleanroom compatibility is part of compatibility with the required cleanliness. Regarding the cleanroom compatibility of equipment/compatibility of equipment with the required cleanliness, see Figure 1 as well as VDI 2083 Part 9.1 and Part 17.
(VDI 2083: Blatt 9.2: 2017-01 Düsseldorf)
Cleanroom installation
Cleanroom or one or several controlled environments together with all associated buildings, air-conditioning systems, connections and utilities (ISO 14644-1:1999, 2.1.3). (VDI 2083: Blatt 4.1: 2006-10 Düsseldorf)
Cleanroom protocol
The cleanroom protocol includes activities during the realisation of a cleanroom project, which serve to maintain a defined level of cleanliness during the construction stage in question; examples are cleanroom apparel, behaviour, the entering of personnel and materials, cleaning and clean assembly. (VDI 2083: Blatt 4.1: 2006-10 Düsseldorf)
Cleanroom suitability
Cleanroom suitability assesses the suitability of an operating material for use in cleanrooms which have been specified in accordance with a regulating body for assessing air cleanliness. The classification criterion in this instance is the emission of particles from the operation material. Cleanroom suitability is an integral part of cleanliness suitability.
- The tests must be carried out in cleanrooms with unidirectional airflows (prevention of cross-contamination).
No other particle sources may influence the test whilst measurements are being performed. The exclusion of foreign particles ensures that only particles emitted from the operating material are detected. Before carrying out measurements, the person concerned must first perform qualitative measurements at the measuring site using random samples without the operating material being present. In this way, no other particle sources should be able to influence the measurements obtained during the classification measurements. The operating material must first be decontaminated using suitable cleaning techniques before it is introduced into the cleanroom (see VDI 2083 Part 4).
(VDI 2083: Blatt 8: 2000-08 E; Düsseldorf)
Cleanroom suitability assesses the suitability of an operating material for use in cleanrooms which have been specified in accordance with a regulating body for assessing air cleanliness. The classification criterion in this instance is the emission of particles from the operation material. Cleanroom suitability is an integral part of cleanliness suitability
(VDI 2083: Blatt 8: 2002-09 Düsseldorf)
Cleanroom suitability of materials
Suitability of materials for use in cleanrooms based on an evaluation of their emission of particulate contaminations (3.1) (particles 3.2).
Note: All contamination criteria relevant to the product in question are taken into consideration.
(VDI 2083: Blatt 17: 2013-06 Düsseldorf)
Cleanroom technology
That area of contamination control which utilizes cleanrooms. Cleanroom technology also includes all the different actions and precautions taken in order to create a working environment in which the level of contamination is controlled (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Cleanwork place
A controlled area with a cleanliness level corresponding to the air cleanliness classes as specified in Part 1
The personnel can stay either with the clean work place (cleanroom) or outside (e.g. clean work bench or clean cabin).
Different types of clean work places can be distinguished by size and constructional demarcation, e.g.:
-cleanroom (personal is working within the room);
-clean cabin (personal only opens the all-enclosed cabin if required);
-cleanroom tent (clean area enclosed by foil)
(VDI 2083: Blatt 2: 1996-02 Düsseldorf)
Clean zone
A defined space in which the concentration of airborne particles is controlled to meet a specified airborne particulate cleanliness. (Federal Standard, Stuttgart 1991)
Dedicated space in which the concentration of airborne particles is controlled, and which is constructed and used in a manner to minimize the introduction, generation, and retention of particles inside the zone, and in which other relevant parameters, e.g. temperature, humidity, and pressure, are controlled as necessary
NOTE This zone may be open or enclosed and may or may not be located within a cleanroom
(ISO 14644-1:1999 (E))
Cluster
Aggregation of molecules. (VDI 2083: Blatt 8.1: 2014-10 Düsseldorf)
CNC
Condensation nucleaus counter (SEMI E44-96, Guide for Procurement and acceptance of minienvironments, 1995)
Collected volatile condensable material (CVCM)
The mass that outgasses from a material and subsequently condenses on a collector surface as specified in ASTM E 595 expressed as a percentage of the initial specimen mass. See also Total Mass Loss. (Military Standard Product Cleanliness Levels and Contamination Control Program MIL-STD-1246C, 11. April 1994)
Colloid (colloidal system)
Heterogeneous substance consisting of a liquid (dispersion medium) in which ultramicroscopic (1nm to 100nm) particles are suspended evenly because of their electrical charges. They exhibit Brownian motion and are subject to cataphoresis. (VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Colony
A collection or group of microorganisms derived from the proliferation of an isolated single organism or group of organisms. (Introduction to Contamination Control and Cleanroom Technology, 1999)
Colony-forming unit (cfu)
Unit for expressing the number of culturable microorganisms. [DIN EN 13098]
Note 1: A colony-forming unit may be formed by one microorganism, a clump of microorganisms or a large number of microorganisms adhering to a particle. [DIN EN 13098]
Note 2: The number of colonies formed can depend on the culture conditions. [DIN EN 13098]
(VDI 2083: Blatt 18: 2012-01 Düsseldorf)
Compatibility of materials with the required cleanliness
Suitability of materials (3.1) for use in clean production environments, established by evaluation.
Note: All contamination criteria relevant to the product in question are taken into consideration.
(VDI 2083: Blatt 17: 2013-06 Düsseldorf)
Compatibility with the required cleanliness
Compatibility with the required cleanliness serves to assess pieces of equipment or air-handling components in view of their use in cleanrooms. It describes the generation or existence of the contamination generated by, or existing on, the piece of equipment or air-handling component. (VDI 2083: Blatt 9.1: 2006-12 Düsseldorf)
Criterion for the assessment of pieces of equipment or air-handling components in view of their use in cleanrooms
Note: The compatibility with the required cleanliness describes the generation or existence of the contamination generated by, or existing on, the piece of equipment or air-handling component.
(VDI 2083: Blatt 9.1: 2021-01 Düsseldorf)
Evaluation of consumables in terms of the compatibility with controlled production environments
Note 1: All contamination criteria relevant to the product in question are taken into consideration (see also Table 1)
Note 2: Cleanroom compatibility is part of compatibility with the required cleanliness. Regarding the cleanroom compatibility of equipment/compatibility of equipment with the required cleanliness, see Figure 1 as well as VDI 2083 Part 9.1 and Part 17.
(VDI 2083: Blatt 9.2: 2017-01 Düsseldorf)
Complex former
A chemical agent with the ability to solubilize metal-containing oxides. (Introduction to Contamination Control and Cleanroom Technology, 1999)
Commissioning
Planned and documented series of inspections, adjustments and tests carried out systematically to set the installation into correct technical operation as specified (ISO 14644-4:2001 (E))
Planned and documented series of inspections, adjustments and tests carried out systematically with the aim of commissioning the cleanroom installation in accordance with requirements for specified normal operation. (VDI 2083: Blatt 4.1: 2006-10 Düsseldorf)
Concentrate (retentate)
That part of the feed in a membrane system which does not pass the membrane. (VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Condensable
Species capable of depositing on a surface by condensation, under cleanroom operating conditions (ISO 14644-8: 2003-09)
Substance, which, under cleanroom operation conditions, is capable of depositing on a surface by condensation (see ISO 14644-8). (VDI 2083: Blatt 9.2: 2009-07 Düsseldorf)
Condensable contaminant
Substance capable of depositing, by way of condensation, on a surface (3.5) under cleanroom operating conditions. (VDI 2083: Blatt 17: 2013-06 Düsseldorf)
Condensation nucleus counter (CNC)
An instrument for counting small airborne particles, approximately 0.01 μm and larger, by optically detecting droplets formed by condensation of a vapor upon the particles. (Federal Standard 209D, Stuttgart 1991)
An instrument for counting small airborne particles, approximately 0.01μm and larger in size, by detecting, with optical methods, droplets formed by condensation of vapor on the particles (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Conditioning
Pretreatment of raw water so as to meet the resin or membrane-specific requirements for avoiding precipitates and biofouling (Section 3.2) in the resins or modules. (VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Consequential nonconformity
For the purposes of this guideline, consequential nonconformities are deviations from specified quality requirements to be fulfilled by the products or persons to be protected through contamination control while the clean facility is in operation, provided that these deviations can be identified to be contamination-control-related.
Note: These definitions apply to all stage to all stage of design, construction and operation of a clean facility. For instance, even planning and design work not allowing to expect fulfilment of requirements and specifications in accordance with the rules of contamination control, must be considered nonconforming.
(VDI 2083: Blatt 11: 2008-01 Düsseldorf)
Consumable
Equipment used in cleanrooms or controlled environments and disposed of as intended after single or multiple use
Note 1: Production facilities, equipment for long-term use and powder-like or gaseous and liquid media are not consumables.
Note 2: Consumables for multiple use, e.g. multiple use cleanroom clothing, can be subjected to cleaning cycles.
(VDI 2083: Blatt 9.2: 2017-01 Düsseldorf)
Contact plate
A small plastic dish overfilled with growth medium so that the level of agar rises above the rim of the plate and used for surface sampling of microorganisms. To take a sample on a flat surface the convex agar surface is firmly pressed against the surface using a gentle rocking motion in order to secure complete contact. (Introduction to Contamination Control and Cleanroom Technology, 1999)
Containment
Something that contaminates. (Introduction to Contamination Control and Cleanroom Technology, 1999)
Technical containment: the use of suitable barriers either to contain as much as possible or to avert the accidental release of biological/chemical agents or ionizing radiation from a closed system (e.g. fermenter, room, building) into the environment. (VDI 2083: Blatt 12: 2000-01 Düsseldorf)
Contaminant
A specific type of contamination. (Military Standard Product Cleanliness Levels and Contamination Control Program MIL-STD-1246C, 11. April 1994)
Contaminant category
Group of contaminants (3.4) with similar chemical properties. [adapted from DIN EN ISO 14644-6] (VDI 2083: Blatt 17: 2013-06 Düsseldorf)
Contaminate
To soil, stain and/or infect by contact or association. (Introduction to Contamination Control and Cleanroom Technology, 1999)
Contamination
Any particulate or non-particulate, molecular, physical or biological entity having a potential of affecting the product or process (ISO 14644-4). (VDI 2083: Blatt 9.1: 2006-12 Düsseldorf)
Any particulate, molecular, non-particulate or biological unit which is capable of exerting a negative influence on the product or process. (VDI 2083: Blatt 4.1: 2006-10 Düsseldorf)
Particulate or non-particulate, chemical, physical or biological entity that can adversely affect the product or process. (adapted from DIN EN ISO 14644-4) (VDI 2083: Blatt 17: 2013-06 Düsseldorf)
Contamination Control
Organized action to control the level of (re)contamination during all processes starting after cleaning up to install. (ASML-Standards, Cleanliness Grades Grade 2: Surface Cleanliness, GSA 07 2310, 2007)
Securing an environment in which the number/concentration of airborne particles and or other relevant contaminants of the direct process environment is controlled or minimised (VDI 2083: Blatt 16.2: 2021-04 Düsseldorf)
Any organized action taken to control the level of contamination. (Military Standard Product Cleanliness Levels and Contamination Control Program MIL-STD-1246C, 11. April 1994)
The overall description of all actions taken in order to gain control of contaminants. Can be used either to product being manufactured or to protect the personnel working in the production, or both (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Controlled area
The surroundings of the clean environment and the external parts of the material locks and personnel locks. (VDI 2083: Blatt 4: 1996 Düsseldorf)
Core area
Area in which a process takes place, and where process and environment interact (ISO 14644-4). (VDI 2083: Blatt 9.1: 2006-12 Düsseldorf)
Corrective action
action to eliminate the cause of a detected nonconformity (International Standard, ISO/FDIS 14001, 2004)
Corrosion
Reaction of a metallic material (3.1) with its environment, producing a measurable change of the material, and leading possibly to an impairment od the function of a metal component or entire system.
Note 1: In most cases, this reaction is electrochemical in nature, but in a few cases, it can also be of a chemical or metal-physical character (corrosion as defined in DIN EN ISO 8044).
Note 2: Corrosion is the term used for metallic materials, whereas ageing is used for plastics and lubricants.
(VDI 2083: Blatt 17: 2013-06 Düsseldorf)
Corrosive
Species that causes destructive chemical change of a surface (ISO 14644-8: 2003-09)
Corrosive contaminant
Substance causing an undesirable, destructive chemical change of a surface (3.5). [adapted from DIN EN ISO 14644-6, corrosive] (VDI 2083: Blatt 17: 2013-06 Düsseldorf)
Critical area
Confined area in which the product or the process in to be protected from defined contamination.
NOTE: Examples for critical areas are safety benches, SMIF-boxes, isolators and others; openings which cannot be avoided are secured by positive pressure.
(VDI 2083: Blatt 4: 1996 Düsseldorf)
Cross-over bench
See Step-over bench (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Cut-off
Molecular mass corresponding to a rejection rate of 90%. (as defined in EN 14652) (VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Declination phase
The stage in the growth curve of microorganisms, when they gradually begin to deteriorate. (Introduction to Contamination Control and Cleanroom Technology, 1999)
Decontamination
The freeing of a person or an object of some contaminating substance such as gas, radioactive material, microorganisms etc. Within the area of contamination control decontamination often refers to the reduction of numbers of living organisms to some lower population level, but not necessarily to zero. (Introduction to Contamination Control and Cleanroom Technology, 1999)
Removal of undesirable material down to a specified level (lSO14644-7). (VDI 2083: Blatt 9.1: 2006-12 Düsseldorf)
Reduction of contamination to a defined level (see also ISO 14644-7). (VDI 2083: Blatt 5.1: 2007-09 Düsseldorf)
Decontamination is the targeted removal of contamination down to a defined level.
Note: The effectiveness is established qualitatively in accordance with specified procedures.
(VDI 2083: Blatt 16.1: 2010-08 Düsseldorf)
Deionized water (DI water, fully desalinated water, FD water)
Water from which ions (anions and cations) of the salts dissolved in it were removed to a predefined degree. (VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Demonstrated equivalence
The condition where a method of measurement has passed a series of tests to show that it gives equivalent results to those of a standard measurement. (Military Standard Product Cleanliness Levels and Contamination Control Program MIL-STD-1246C, 11. April 1994)
Design qualification (DQ)
The basic design process shall reach closure in a qualification verifying conformance with the requirements as specified in the user requirements specification (URS). The following items shall be verified in particular (see also VDI 2083 Part 3):
- cleanroom concept
- materials and personnel flow diagrams
- machine arrangement drawing
- description of installation including design drawing
- plans and drawings
- incorporation of all agreed additional requirements
- interfaces/limits to the scope of supply
(VDI 2083: Blatt 4.1: 2006-10 Düsseldorf)
Desorption
The release of an adsorbed substance to the gas or liquid phase, the reverse process to ->adsorption. (VDI 2083: Blatt 9.2: 2009-07 Düsseldorf)
Diffuse reflection
Reflection in which the flux is scattered in many directions by diffusion at or below the surfaces. (ECSS-Q-ST-70-05C, 2009)
Discrete-particle counter (DPC)
An instrument, such as an optical particle counter or a condensation nucleaus counter, capable of resolving responses from individual particles. (Federal Standard 209D, Stuttgart 1991)
An apparatus used for the numerical counting of discrete particles. (Introduction to Contamination Control and Cleanroom Technology, 1999)
Disinfect
To free from pathogenic organisms, or to render them inert. Within contamination control the word disinfect is often used in order to express the gross elimination of all organisms (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Disinfectant
An agent that disinfects. The term is usually applied to agents used on in animate objects (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Disinfection
Elimination, destruction or deactivation of microorganism on objects or surfaces (see also ISO 14644-5). (VDI 2083: Blatt 5.1: 2007-09 Düsseldorf)
Disinfection is a process aiming to destroy, or irreversibly inactivate, bacteria, fungi and viruses found an and in objects. In the context of this VDI guideline, disinfection is considered to be a count of 1000000 organisms capable of reproduction (socalled colony-forming units -CFUs, germ count), only 10 should be detectable after disinfection. Disinfection is an important measure for discontinuing infection chains.
Note 1: Technically, a distinction is made between disinfection and sterilization. In the case of sterilization. In the case of sterilization, all bacteria, fungi and viruses must be irreversibly inactivated irrespective of the original count.
Note 2: The term disinfection is also used to designate sanitizing, a term common in water and food applications. Both are selective measures that will not destroy all microorganisms (see also sterilization).
Note 3: Note applies to German version only.
(VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Inactivation of all pathogens and a multitude of other microorganisms down to a level adequate to the hygienic use of the facility. [DIN EN 1672-2] (VDI 2083: Blatt 18: 2012-01 Düsseldorf)
Dissociation
The process in which a molecule is broken into fragments such as atoms, radicals. (VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Documentation
The results from requalification or testing of each installation to prove continued compliance shall be recorded and submitted as a comprehensive report, along with a statement of compliance or non-compliance with the specified tests. (ISO 14644-2:2000 (E))
DOP
dioctylphthalate, synonym (2-ethylhexyl)phthalate (ECSS-Q-ST-70-05C, 2009)
a liquid that can be broken up into particles of minute size, e.g. smoke. (Introduction to Contamination Control and Cleanroom Technology, 1999)
DOP aerosol
Finely dispersed DOP particles in a gas (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Dopant, doping agent
Species which, after sorption, is incorporated in the bulk of a product and is capable of changing the properties of materials, even in trace amounts
NOTE. Typical examples of bulk modifiers in microelectronics are dopants and critical metal contaminants like, e.g. Na, Cu or Fe.
(ISO 14644-8: 2003-09)
Substance which, following -> sorption and/or diffusion, will migrate into the bulk of a product, and which, even as a trace constituent, is capable of modifying the characteristics of materials.
Note 1: Common examples of dopants are compounds of P, B, As, Sb, Ga (see ISO 14644-8).
Note 2: The process of doping can be an intended process step or an undesirable contamination process, e.g. through ->AMC.
(VDI 2083: Blatt 9.2: 2009-07 Düsseldorf)
Substance which, after adsorption, is incorporated in the bulk of a product and is capable of changing the properties of materials, even in trace amounts.
Note: Typical example of dopants are substances changing the electrical properties of semiconductor materials, e.g. critical metal contaminants such as P, B and As.
(VDI 2083: Blatt 17: 2013-06 Düsseldorf)
DPC
Discrete Particle Counter (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
DRIFT
diffuse reflection infrared fourier transform (ECSS-Q-ST-70-05C, 2009)
Dry heat sterilization
Thermal sterilization at relative humidities less than 100%. It is less efficient than moist heat where the relative humidity is 100% and required longer exposure times at higher temperatures (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
DTGS
deuterated triglycine sulphate IR detector (ECSS-Q-ST-70-05C, 2009)
Dust
Solid material that can be found on surfaces or suspended in gases. (Introduction to Contamination Control and Cleanroom Technology, 1999)
D-value
The decimal reduction time. The D-value is defined as the sterilization time, for a physical or chemical agent, used to obtain a 90% reduction in the number of microorganisms (one log) present in a sample (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Electrical conductivity of water
Conductivity of water as a measure of the total amount of ions dissolved in the water; units: µS/cm and mS/m. (VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Electrical resistance of water
Electrical resistance of water as a measure of the total amount of ions dissolved in the water, unit: Ω cm or M Ω cm.
Note: Electrical resistance is the reciprocal of electrical conductivity.
(VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Electrostatic charging
Difference in potential, generated by friction and separation of materials (triboelectric charging), or by the action of an electric field (electrostatic induction, or influence).
Note 1: The magnitude of the charging potentials depends largely on the tendency of the materials to accumulate charges and on the relative humidity of ambient air.
Note 2: The limits listed in this guideline (resistance, charge, etc.) are but examples and have to be agreed upon between user and supplier for the object in question. Even potentials below 10V can damage or destroy electronic components; this fact should be given consideration in the selection of suitable materials.
(VDI 2083: Blatt 17: 2013-06 Düsseldorf)
Electrostatic discharge (electrostatic dissipation, ESD)
Spontaneous transfer of electrostatic charge between two bodies or materials at different electrostatic potentials
Note 1: An electrostatic discharge occurs through direct contact or is induced by an electrostatic field.
Note 2: Regarding the determination of electrostatically charged materials/material combinations, see SEMI E78-0309.
(VDI 2083: Blatt 9.2: 2017-01 Düsseldorf)
Spontaneous transfer of charges between two bodies or materials at different electrostatic potentials, caused by direct contact or induced by an electrostatic field.
Note: Electrostatically charged (combinations of) materials can be determined by means of electrostatic-field measurements in accordance with, e.g. SEMI E78-0309)
(VDI 2083: Blatt 17: 2013-06 Düsseldorf)
Enclosure
A physical barrier between the localized environment and the surroundings. (SEMI E44-96, Guide for Procurement and acceptance of minienvironments, 1995)
Endotoxin
Endotoxins are biochemical substances in the external membrane of Gram-negative bacteria (lipopolysaccharides). Endotoxins are pyrogens and can induce fever when brought into contact with mucosae and when entering the blood of humans and some animals species. Endotoxins are pyrogens and can induce fever when brought into contact with mucosae and when entering the blood of humans and some animal species. Endotoxins are released after cell death and are biologically effective at even the minutest concentrations (lower pg/m range). Unlike the bacteria from which they originate, endotoxins are highly heat-resistant, withstanding even sterilization. (VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Entrance plane
A plane perpendicular to the unidirectional airflow located immediately upstream of the region. (Federal Standard 209D, Stuttgart 1991)
A plane perpendicular to the unidirectional airflow located immediately upstream of the region of interest (typically the work area unless otherwise specified) and having the same dimensions an the cross section of the clean zone perpendicular to the direction of the airflow. (Federal Standard FED-STD-209E / 11. September 1992; airborne particulate cleanless classes in cleanrooms and clean zones)
Environmental management system (EMS)
part of an organization’s management system used to develop and implement its environmental policy and manage its environmental aspects (International Standard, ISO/FDIS 14001, 2004)
EP
Electropolished (SEMI F28-1103, test method for measuring particle generation from process panels, 2003)
EPS
expanded polystyrene (SEMI E137-0705, guide for final assembly, packaging, transportation, unpacking and relocation of semiconductor manufacturing equipment, 2004)
Equipment/ piece of equipment
Equipment includes e.g., the facilities or objects listed hereafter, which are brought into a controlled environment.
This list of examples of pieces of equipment is based on the list given in VDI 2815 Part 5:
-production facilities (such as bonders, assembly equipment, filling stations)
-measuring and testing equipment (such as inspection facilities, microscopes)
-equipment for transport and handling (such as linear axles, conveyor belts, robots)
-storage units (such as boxes, buffers)
-organization tools (such as workpiece carriers
-interior furnishings (such as tables, chairs)
-elements of interior work (such as walls, doors, ceilings, floors)
(VDI 2083: Blatt 9.1: 2006-12 Düsseldorf)
facilities or objects listed hereafter, which are brought into a controlled environment:
-production facilities (such as bonders, assembly equipment, filling stations)
-measuring and testing equipment (such as inspection facilities, microscopes)
-equipment for transport and handling (such as linear axles, conveyor belts, robots)
-storage units (such as boxes, buffers)
-organization tools (such as workpiece carriers
-interior furnishings (such as tables, chairs)
-elements of interior work (such as walls, doors, ceilings, floors)
(VDI 2083: Blatt 9.1: 2021-01 Düsseldorf)
Equivalent diameter
The diameter of a reference sphere having the same properties and producing the same response in the sensing instrument as the particle being measured (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
ESD
electrostatic discharge (ECSS-Q-ST-70-05C, 2009)
Cleanroom technology terms from F to J
Facultative anaerobe
Microorganisms which are able to grow under either anaerobic or aerobic conditions (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Fall out plate
A Petri dish containing sterile agar medium used to determine the presence of microorganisms in the air. A fall out plate is placed on a surface and exposed to the surrounding air. Particles suspended in the air will be deposited in the agar as a result of the force of gravity and air movements (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
FDA
Food and Drug Administration (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Fermentation
An enzymatic decomposition, especially of carbohydrates as used in the production of alcohol, bread, vinegar and other food or industrial materials (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
FFT
Fast fourier transformation (SEMI E44-96, Guide for Procurement and acceptance of minienvironments, 1995)
FFU (filter fan unit)
module consisting of one or several fans and one or several filter elements for the creation of a clean airflow (VDI 2083: Blatt 16.2: 2021-04 Düsseldorf)
Fiber
A fiber is defined (ISO 14644) as a particle that has an aspect (length-to-width) ratio of 10 or more (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Fibre
Particle having an aspect (length-to-width) ratio of 10 or more (ISO 14644-1:1999 (E))
Particle where the length is at least 10 times the width (VDI 2083: Blatt 1: 2003-06 Düsseldorf)
Filter life
Time of operation of a filter until the maximum permissible passage of residual AMC concentration (protection goal) is reached, or until maximum permissible -> breakthrough.
Note: This definition deviates from the one usual for particle filtration where the filter is defined by the reaching of a maximum permissible pressure drop. The pressure drop across an -> AMC filter, however, is not a function of the filter load.
(VDI 2083: Blatt 9.2: 2009-07 Düsseldorf)
Flow uniformity
Unilateral flow profile where the flow velocities measured at various points will not vary by more than the specified percentage with respect to the average flow velocity. (VDI 2083: Blatt 4.1: 2006-10 Düsseldorf)
Fluorescent marker
Agents emitting visible light after being excited by short – wavelength light up to ultraviolet wavelengths or by electron bombardment. (VDI 2083: Blatt 18: 2012-01 Düsseldorf)
FMEA
Failure Mode Effects Analysis. A method of accessing risks. (Introduction to Contamination Control and Cleanroom Technology, 1999)
Fouling of ion exchangers
Accumulation of mainly organic substances, leading to a decrease in efficiency of the ion exchanger. (as defined in DIN 54400)
Note: See also fouling of membranes.
(VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Fouling of membranes (plugging)
Reduction in permeability of membranes for water due to deposits on the membrane surface and/or in the membrane pores. (as defined in DIN 19645) (VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Fourier transformation
Mathematical process used to covert an amplitude-time spectrum to an amplitude-frequency spectrum or vice versa. (ECSS-Q-ST-70-05C, 2009)
Friction
Dissipation of mechanical energy as relative motion occurs, begins or ends between materials in contact.
Note: Solid-body friction is a specific form of sliding friction, where surface elevations are planed (reshaped and/or removed), which in turn gives rise to the emission of particulate contaminations (3.1).
Sliding friction depends on the magnitude of the normal force, FN, acting between the surface (3.5) of the material pair, on the coefficient of sliding friction, µGL, and the relative velocity, vrel, of the sliding surfaces rubbing against each other. It is determined by the roughness and material type of the interacting surfaces. The friction coefficient, µGL, is a material-specific quantity, defined as the ratio of frictional force over normal force.
(VDI 2083: Blatt 17: 2013-06 Düsseldorf)
FTA
Failure Tee Analysis. A method for accessing risks. (Introduction to Contamination Control and Cleanroom Technology, 1999)
FTIR
Fourier transform infrared (sepctrometry) (ECSS-Q-ST-70-05C, 2009)
f-value
The time needed to reduce the total number of microorganisms in a certain medium at 121 °C (using an autoclave) (Introduction to Contamination Control and Cleanroom Technology, 1999)
Garment system
A set of clothing which when worn together provides optimum protection to both wearer and the environment. (Introduction to Contamination Control and Cleanroom Technology, 1999)
Generation
The act or process of reproduction (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Generation time
The time needed for the act or process of reproduction, e.g. the time needed for one microorganism to divide into two daughter cells (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Germ count
Number of colony-forming units that will form macroscopically countable colonies unter specified condition. (based on DIN 10192-1)
Note: The common unit is the number of colony-forming units (CFUs); the term “colony number” is also in use.
(VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Germ reduction
Reduction of the number of viable microorganisms. (VDI 2083: Blatt 18: 2012-01 Düsseldorf)
GFAAS
Graphite furnace atomic absorption spectroscopy (SEMI E44-96, Guide for Procurement and acceptance of minienvironments, 1995)
GLP
Good Laboratory Practice (Introduction to Contamination Control and Cleanroom Technology, 1999)
GMP
Good Manufacturing Practice. A series of rules, used to ensure that the product is always produced in the same way with respect to cleanliness, identity, effect and content. (Introduction to Contamination Control and Cleanroom Technology, 1999)
Ground resistance
Electrical resistance between an electrode placed at an arbitrary point on the surface of a piece of equipment and the groundable point of that piece of equipment, which has a potential of 0 V (mass). (VDI 2083: Blatt 9.1: 2006-12 Düsseldorf)
HACCP
Hazard Analysis Critical Control Point. HACCP is a risk analysis mostly used by the food and beverage industry (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
handling zone (product space)
zone in which the product is manually or automatically handled before, during, and after the process (VDI 2083: Blatt 16.2: 2021-04 Düsseldorf)
HAZOP
Hazard and Operability studies of the International Social Security Association. A method for assessing risks (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
HEPA
High Efficiency Particulate Air Filter. A HEPA filter is defined as a filter for ventilation air with the ability to reduce the number of particles of 0.3 µm or greater in size in the air by at least 99.97 % as measured with a DOP aerosol. (Introduction to Contamination Control and Cleanroom Technology, 1999)
Humic substances
Organic matter, typically plant degradation products contained in surface water. Interfering with strongly basic anion exchangers. (VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Hydrophobic
Not readily wetted by water (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Hydrophilic
Water wettable (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
IES
Institute of Environmental Sciences (ECSS-Q-ST-70-05C, 2009)
Impaction
Physical phenomenon taking place when the movement of a particle suspended in a gas is stopped by an obstruction present in the gas stream. When a gas stream is forced towards a solid material, the gas itself will alter direction. Particle suspended in this gas stream, if they have a mass great enough, will not follow the gas stream due to inertia, and will continue in a tangential direction and finally hit the solid material. Impaction is often utilized in apparatus used for the collection of solid contaminants. (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Impingement
Collection of airborne particles in liquids by means of several underlying mechanisms such as impaction, diffusion, interception and sedimentation.
[VDI 4252 Part 3 and VDI 4257 Part 2]
(VDI 2083: Blatt 18: 2012-01 Düsseldorf)
Impinger
Purpose-made gas-washing bottle made of glass or Teflon, serving to sample air constituents. In the impinger, the air is brought into contact with a sampling liquid (solvent or sorption medium) (VDI 2083: Blatt 9.2: 2009-07 Düsseldorf)
Special gas-washing bottle made of glass or Teflon, serving to collect airborne substances. The air is brought into contact with a liquid (solvent or sorption medium). [VDI 2083 Part 8.1] (VDI 2083: Blatt 18: 2012-01 Düsseldorf)
An apparatus used for the collection of contaminants in air and other gases when the gas is forced through liquid in a flask (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Impregnation agent
Substance with which a sorption agent is impregnated in order to allow, by way of chemical reactions (cf. chemisorption) between the impregnation agent and the adsorbed substance, the removed of -> AMC which cannot economically be removed from gas streams by mere physisorption. (VDI 2083: Blatt 9.2: 2009-07 Düsseldorf)
Incubation
The process of maintaining warm conditions in which microorganisms or other cells can replicate when provided with appropriate media (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Incubator
An apparatus for maintaining a constant and suitable temperature for the development of eggs, cultures of microorganisms or other living cells (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Increase in salinity
Increase of the salt concentration in treated water compared to raw water as a result of the excess regenerating agents which is indispensable for the regeneration of ion exchangers and the neutralization of the regeneration effluents. (VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Inductive charging
Moving conductors carrying art electric current in a static magnetic field, or the variation in time of a magnetic field (B-field) around an electric current which is constant in time and space. will cause induction which may result in a build-up of surface potentials. (VDI 2083: Blatt 9.1: 2006-12 Düsseldorf)
Inert
Having no action. Not reacting with other elements (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Inertia
Inability to move spontaneously. Inertia is used in many sampling techniques and is based on the inability of a particle to be collected due to both mass and speed of movement of the particle (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Infrared spectroscopy
Spectroscopy in the infrared region of the electromagnetic spectrum, i.e. with wavelength range from approximately 0.78 µm to 1000 µm (wave number range (12820 cm-1 to 10 cm-1) (ECSS-Q-ST-70-05C, 2009)
In operation
Condition where the installation is functioning in the specified manner, with the specified number of personnel present and working in the manner agreed upon (VDI 2083: Blatt 1: 2003-06 Düsseldorf)
ready and in operation while producing (VDI 2083: Blatt 16.2: 2021-04 Düsseldorf)
Installation
Cleanroom or one or more clean zones, together with all associated structures, air-treatment systems, services, and utilities (ISO 14644-1:1999 (E))
Installation qualification (IQ)
A systematic series of inspections, measurements and tests (and modifications, if necessary) shall be carried out in order to ensure the compliance of each and every part of the cleanroom installation which the design requirements. The following items shall be verified in particular:
- inspection and tests for completeness as well as quality in comparison with the specifications given
- confirmation of compliance with safety regulations, ergonomic requirements and the relevant regulations and standards
- acceptance pf supplier certificates
- interfaces between systems and trades
- completeness of the cleanroom installation
- spare parts package
- installation and on-site testing of terminal filters
- agreed documentation
(VDI 2083: Blatt 4.1: 2006-10 Düsseldorf)
Installed filter system
System consisting of filter medium, filter frame and retainer, installed in the ceiling, wall, in a unit or an air duct. (VDI 2083: Blatt 4.1: 2006-10 Düsseldorf)
Insulation material
Material with a very limited mobility of charges, as a consequence of which any occurring charges do not dissipate.
Note: For instance, the surface resistance (3.4) of an insulating packaging material as specified in DIN IEC 61 340-1 (VDE 0300-1) has be at least 1 x 1011 Ω ore more under the specified conditions.
(VDI 2083: Blatt 17: 2013-06 Düsseldorf)
Integrated minienvironment
The minienvironments in an integral part of the tool. (SEMI E44-96, Guide for Procurement and acceptance of minienvironments, 1995)
ME which is permanently connected to, or integrated in, the production facility and is thus an inherent part of the production facility (VDI 2083: Blatt 16.2: 2021-04 Düsseldorf)
Integrated SMIF
A unit including SMIF port and a mechanism for indexing the port door. The entire unit being incorporated within the tool. (SEMI E44-96, Guide for Procurement and acceptance of minienvironments, 1995)
Internal audit
systematic, independant and documented process for obtaining audit evidence and evaluating it objectively to determine the extent to which the environmental management system audit criteria set by the organization are fulfilled (International Standard, ISO/FDIS 14001, 2004)
Interested party
person or group concerned with or affected by the environmental performance of an organization (International Standard, ISO/FDIS 14001, 2004)
Intrinsic conductivity of water
Electrical conductivity of pure water.
Note: Due to the intrinsic dissociation of water into H3O+ and OH– -ions which a concentration of 10-7 mol/ l each (pH=7), at 25°C, the electrical conductivity of pure water is 0,05483 µS/cm (see EN 27888); this corresponds to an electrical resistance of approximately 18,24 M Ω cm.
(VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
IPA
isopropyl alcohol (ECSS-Q-ST-70-05C, 2009)
isopropyl alcohol (2-propanol) (SEMI E137-0705, guide for final assembly, packaging, transportation, unpacking and relocation of semiconductor manufacturing equipment, 2004)
IR
Infrared (ECSS-Q-ST-70-05C, 2009)
ISO
International Organization for Standardization (ECSS-Q-ST-70-05C, 2009)
Isoaxial
A condition of sampling in which the direction of the airflow into the sampling probe inlet is in the same as that of the unidirectional airflow being sampled. (Federal Standard 209D, Stuttgart 1991)
Isokinetic sampling
The condition of isoaxial sampling in which the mean velocity of the air entering the probe inlet is the same as the mean velocity of the unidirectional airflow at that location. (Federal Standard 209D, Stuttgart 1991)
The condition of isoaxial sampling in which the mean velocity of the air entering the probe inlet is the same as the mean velocity of the unidirectional airflow at the location (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Item
Anything that can be individually described considered, examples including:
– an activity
– a process
– a product
– an organization
– a system
– a person
– a combination of the aforementioned items
(VDI 2083: Blatt 11: 2008-01 Düsseldorf)
IUPAC
International Union of Pure and Applied Chemistry (ECSS-Q-ST-70-05C, 2009)
Cleanroom technology terms from K to O
LAF
Laminar Airflow. A theoretical situation where the air is moving in absolutely parallel streams. In practice very hard to achieve. LAF is not used frequently today. A more accurate term to use is UDF (Unidirectional Flow9. (Introduction to Contamination Control and Cleanroom Technology, 1999)
Lag phase
The early period in the growth pattern of microorganisms when growth or cell division is slow, following inoculation into a culture medium (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
LAL test (Limulus Amebocyte Lysate test)
Test system that determines the coagulation/clotting of amebocyte lysate extracted from the blood of horseshoe crabs (limulus polyphemus) with lipopoly-sacchiarides in the cell walls of Gram-negative bacilli. The test system reacts to as little as 100 to 1000 Gram-negative bacteria per ml; however, it only responds to endotoxin (LPS) released by Gram-negative bacteria. The results are expressed in the international unit EU (endotoxin units). (VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Laminar flow
A flow of parallel streams in the same direction. (Introduction to Contamination Control and Cleanroom Technology, 1999)
LCS
Laser Current Sensor (SEMI E54.10-0600, Specification for sensor/actuator network specific device model for an in-situ particle monitor device, 2000)
Lethal
Deadly, fatal (Introduction to Contamination Control and Cleanroom Technology, 1999)
Liquor ratio
The ratio of liquor to the dry weight of the cleanroom garments being washed. (VDI 2083: Blatt 5.2: 2008-10 Düsseldorf)
Load collective
<tribology> Parameters of input quantities acting on material pair under fictional load.
Note: A load collection is commonly composed of the normal force and the relative velocity between the materials, the duration of load application, and the path lengths covered between the materials (3.1).
(VDI 2083: Blatt 17: 2013-06 Düsseldorf)
Logarithmic phase
Logarithmic growth phase, the stage of active division in the growth pattern of microorganisms (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Macroparticle
Particle with an equivalent diameter greater than 5 µ (ISO 14644-1:1999 (E))
Particle whose equivalent diameter excessds 5µm (VDI 2083: Blatt 1: 2003-06 Düsseldorf)
Manufacturing
Making a product from raw or semi-finished materials ready for cleaning. (ASML-Standards, Cleanliness Grades Grade 2: Surface Cleanliness, GSA 07 2310, 2007)
Material
Any solid or paste-like material or surface coating.
Note: Pulverised, gaseous and liquid media are not considered within the scope of this guideline.
(VDI 2083: Blatt 17: 2013-06 Düsseldorf)
MCT
mercury cadmium telluride IR detector (ECSS-Q-ST-70-05C, 2009)
Measuring method
Method for determining measurands.
Note: The measuring method used depends on the sampling.
(VDI 2083: Blatt 18: 2012-01 Düsseldorf)
Measuring technique
Method for the generation of measured values. (VDI 2083: Blatt 9.2: 2009-07 Düsseldorf)
Medium
A substance used for the culture of microorganisms (Introduction to Contamination Control and Cleanroom Technology, 1999)
Membrane methods
For the purpose of this guideline, membrane methods are:
-reverse osmosis (RO)
-ultrafiltration (UF)
-nanofiltration (NF)
-microfiltration (MF)
-continuous electrodeionization (CEDI)
-electrodialysis (ED)
-electrodialysis with polarity reversion (EDR)
(VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Membrane types
-Anion membrane: membrane selectively permeable for anions (negative ions) while retaining cation
-Cation membrane: membrane selectively permeable for cations (positive ions) while retaining anions
-Composite membrane: membrane consisting of various laminates, a thin separating layer made from various materials
-Symmetric membrane: membrane acting as separating layer throughout its thickness
-Asymmetric membrane: membrane consisting of a thin separating layer and a porous supporting layer
(VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Microbiology
The science which deals with the study of microorganisms (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Micrometer (µm)
A unit of measurement equal to onemillionth of a meter, or approximately thirty-nine millionths of an inch (0,000039 inch), or, 25 microns is approximately 0.001 inch. The micrometer has replaced the micron in the SI system of measurement. (Military Standard Product Cleanliness Levels and Contamination Control Program MIL-STD-1246C, 11. April 1994)
One thousand of a millimeter, or one millionth of a meter (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Minienvironment (ME)
confined, isolated product environment designed to protect the product against contamination
Note 1: Sources of contamination are, e.g., human beings and other, adjacent processes or process environments.
Note 2: It has proven beneficial to distinguish various ME types (see Figure 2)
Note 3: Transport and storage containers are MEs as defined in this standard. They can be passive or active MEs.
(VDI 2083: Blatt 16.2: 2021-04 Düsseldorf)
Minienvironment input/output
Means to transfer cassettes or substrates into/ out of a minienvironment. (SEMI E44-96, Guide for Procurement and acceptance of minienvironments, 1995)
MNS
Median Noise Sensor (SEMI E54.10-0600, Specification for sensor/actuator network specific device model for an in-situ particle monitor device, 2000)
Module types (membrane module types)
The following module types are used in membrane methos:
-spiral-wound module
-hollow-fibre module
-capillary module
-plate module
-tubular module
-cushion module
(VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Mold
A large group of fungi (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
MPPS
Most penetrating particle size (SEMI E44-96, Guide for Procurement and acceptance of minienvironments, 1995)
Moist heat sterilization
Sterilization by heart at 100% relative humidity (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Molecule
A particle consisting of at least two identical or different atoms being held together by covalent bonds. Molecules are the smallest parts of compounds still having the properties of the compounds and consisting of stable aggregates of atoms. (VDI 2083: Blatt 9.2: 2009-07 Düsseldorf)
Molecular/chemical contamination
The undesirable and perceivable molecular modification of substances and their contamination of substances and their contamination or degradation, caused by contamination, regardless of the contamination path (e.g. from the gas phase, as a particle, as a germ) (see also ISO 14644-6).
(VDI 2083: Blatt 9.2: 2009-07 Düsseldorf)
Monodisperse aerosol
An aerosol which contains particles that are all same size (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Monitoring
Immediate systematic recording, observation and checking of measurands, core functions being
- data recording,
- comparison to specifications; triggering alerts, if required,
- representation/visualization, and
- data storage/archiving
(VDI 2083: Blatt 3.1: 2012-06 Düsseldorf)
Monitoring
The routine determination of airborne concentrations, as well as the other relevant conditions, in cleanrooms and clean zones. (Federal Standard 209D, Stuttgart 1991)
Observations made by measurement in accordance with a defined method and plan to provide evidence of the performance of an installation
NOTE This information may be used to detect trends in operational state and to provide process support
Routine monitoring of airborne particle concentration and other parameters shall be performed according to a written plan
NOTE Monitoring is normally performed with the installation in the operational state
(ISO 14644-2:2000 (E))
Morphology
Physical shape of an object (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Nanoscale
property of particle within the size range from 1nm to 100nm (VDI 2083: Blatt 1.1: 2013-01 Düsseldorf)
Nanoparticle (nanoscale particle, ultrafine particle)
particle whose three outer dimensions are nanoscale (VDI 2083: Blatt 1.1: 2013-01 Düsseldorf)
NC
Noise criteria
Non-carbonate hardness (permanent hardness)
That contribution to total hardness which is not bonded to hydrogen carbonate. (VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Nonconformity
non-fulfilment of a requirement (International Standard, ISO/FDIS 14001, 2004)
For the purpose of this guideline, nonconformities are, e.g., exceedances of limits given in the contamination control specifications for a facility as agreed between the parties involved. (VDI 2083: Blatt 11: 2008-01 Düsseldorf)
Non-particulate contamination
Non-particulate contamination are precipltates, condensates, filmlike deposits or diffusion products with varying physical states (ionic components, radio-active, reactive materials or allergens, endotoxins, droplets etc.). (VDI 2083: Blatt 4: 1996 Düsseldorf)
Liquid or paste-like, film-like contamination having the potential to affect the process, the product, the personnel or the facilities. (VDI 2083: Blatt 9.1: 2006-12 Düsseldorf)
Nonunidirectional airflow
Airflow which does not meet the defintion of unidirectional airflow; previously referred to as “turbulent” or “non-laminar” airflow. (Federal Standard 209D, Stuttgart 1991)
Air distribution where the supply air entering the clean zone mixes with the internal air by means of induction (ISO 14644-4:2001 (E))
Air distribution where the supply air entering the room mixes with the internal air by means of induction. This type of air distribution results in dilution of the concentration of particles and/or other contaminants (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Non-Volatile Residue (NVR)
Material remaining after evaporation of a liquid. Units are determined by the test method used. (Military Standard Product Cleanliness Levels and Contamination Control Program MIL-STD-1246C, 11. April 1994)
not in operation (production facility at rest)
ready and in operation while not producing (VDI 2083: Blatt 16.2: 2021-04 Düsseldorf)
NVR
non-volatile residue (ECSS-Q-ST-70-05C, 2009)
Obligate anaerobe
Microorganisms that can grow only in the complete absence of molecular oxygen. Some obligate anaerobe microorganisms are killed by oxygen (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Objectionable organism
Organism that, by its very nature, represents a particular health hazard and must, therefore, not be present and must not be detectable in any 100-ml sample. (VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Objective evidence
Information which can be proven true, based on facts obtained through observation, measurement, test or other means. (VDI 2083: Blatt 11: 2008-01 Düsseldorf)
Occupancy state
Occupancy states for cleanrooms (as built, at rest, in operation) are defined in VDI 2083 Part 1. The modes of operation for pieces of equipment shall be agreed. (VDI 2083: Blatt 9.1: 2006-12 Düsseldorf)
States for cleanrooms (as built, at rest, in operation) as defined in DIN EN ISO 14644-1, 4.1)
Note 1: The modes of operation for pieces of equipment shall be agreed.
(VDI 2083: Blatt 9.1: 2021-01 Düsseldorf)
OEL value
OEL values (occupational exposure limits) are limit values for hazardous substances in breathing air, specified to protect occupational health and safety (OHS).
Note 1: Based on OEL values, occupational exposure bands (OEB) or OEL classes can be defined.
Note 2: Figure 2 compares the concentration bands of the OEL-classes to specific barrier techniques.
(VDI 2083: Blatt 16.1: 2010-08 Düsseldorf)
OEM
Original equipment manufacturer (SEMI E44-96, Guide for Procurement and acceptance of minienvironments, 1995)
Offline measuring technique
Measuring technique where measured data are transmitted to a master data processing system at regular intervals, with some delay between recording and transmission. (VDI 2083: Blatt 3.1: 2012-06 Düsseldorf)
Online measuring technique
Measuring technique where measured data are transmitted immediately, almost at the instant of recording, to a master data processing system. (VDI 2083: Blatt 3.1: 2012-06 Düsseldorf)
OPC
Optical Particle Counter (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Operator
Person working in the cleanroom performing work or carrying out process procedures (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Operation
Condition where the installation is functioning in the specified manner, with the specified number of personnel present and working in the manner agreed upon. (VDI 2083: Blatt 1: 2013-01 Düsseldorf)
Operational Cleanroom
A cleanroom or facility in normal operation, with all services functioning and with equipment and personnel, if applicable, present and performing their normal work functions in the facility. (Introduction to Contamination Control and Cleanroom Technology, 1999)
Condition where the installation is functioning in the specified manner, with the specified number of personnel present and working in the manner agreed upon (ISO 14644-1:1999 (E))
Operational qualification (OQ) or functional qualification (FQ)
A series of tests and measurements shall be carried out in order to ensure the functioning of all parts of the cleanroom installation in such a way as to meet the conditions required for the occupancy states “as built”, and “at rest”. The following items shall be verified in particular:
- proper functioning of utilities and auxiliary equipment
- calibration of sensors and measuring equipment
- testing of open- and closed-loop control systems
- confirmation of reserve capacity of the air-conditioning systems
- determination of barrier function of the controlled environment, where specified
- if necessary, proof and recording of airflow profiles or air change rates as a function of the type of flow
- filter leak test
- if necessary, verification whether or not the required over- or under-pressure (depending on the purpose of installation) is reached
- determination of the particulate air cleanliness class
- verification if the requirements concerning temperature and relative humidity can be met
- determination of sound pressure, illuminance and type of illumination
(VDI 2083: Blatt 4.1: 2006-10 Düsseldorf)
Operator inspection
That part of the quality inspection required for quality control which is performed by the operator himself. (DIN 55350-17)
Note 1: “Operator inspection” must be distinguished from “operator control” which is “that part of quality control which is performed by the operator himself”.
Note 2: “Operator inspection” must be distinguished from “self-inspection” and “third-party inspection”, the latter two terms stating whether a quality inspection is performed by the manufacturer or by a different body.
(VDI 2083: Blatt 11: 2008-01 Düsseldorf)
organic
Species based on carbon and also containing hydrogen, with or without oxygen, nitrogen or other elements (ISO 14644-8: 2003-09)
Organic contaminant
Almost all compounds containing carbon; exceptions include carbon monoxide, carbon dioxide, carbon disulphide, carbonic acid, carbonates. (VDI 2083: Blatt 17: 2013-06 Düsseldorf)
organization
Company, corporation, firm, enterprise, authority or institution, or part or combination thereof, whether incorporated or not, public or private, that has its own functions and administration. (International Standard, ISO/FDIS 14001, 2004)
Osmotic pressure
Pressure differential caused by water transport through a semi-permeable membrane that separates two salt solutions of different concentration levels.
Note: In reverse osmosis, the osmotic, pressure must be overcome.
(VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Outgasing
Release of a molecular species in the gaseous or vapour state from a material (ISO 14644-8: 2003-09)
The emission of chemical substances into the gas phase by a material under typical specified cleanroom conditions (temperature, relative humidity and pressure). (VDI 2083: Blatt 9.1: 2006-12 Düsseldorf)
The release of a molecular substance, or of molecular substance, in the gaseous or vapour state, from a material. (VDI 2083: Blatt 9.2: 2009-07 Düsseldorf)
Release of a substance, or of molecular substance, in the gaseous or vapour state, from a material. (VDI 2083: Blatt 8.1: 2014-10 Düsseldorf)
Chemical compounds in the gaseous or vapour state released from a material under typical specified conditions (temperature, relative humidity and pressure)
Note: see also VDI 2083 Part 17
(VDI 2083: Blatt 9.2: 2017-01 Düsseldorf)
Overpressure
A term used in a cleanroom if the pressure in the room is higher than in the surrounding envireonment. Overpressure is utilized to reduce the risk of contaminants entering critical environments (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Oxidant
Species which, upon deposition to a product or surface of interest, results in the formation of an oxide (ISO 14644-8: 2003-09)
Cleanroom technology terms from P to T
Parasite
An organism that derives its nutrients from other living organisms (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Particle
An object of solid or liquid composition, or both, and generally between 0.001 and 1000 µm in size. (Federal Standard 209D, Stuttgart 1991)
Solid or liquid object which, for purposes of classification of air cleanliness, falls within a cumulative distribution that is based upon a threshold (lower limit) size in the range from 0,1 µm to 5 µm (ISO 14644-1:1999 (E))
Minute piece of matter with defined physical boundaries
NOTE For classification purposes refer to ISO 14644-1
(ISO 14644-4:2001 (E))
For the purpose of this Guideline, a particle is a minute piece of matter with defined physical boundaries.
Microorganisms are particles which can multiply under favourable conditions.
Fibres are particles with a length of more than five times the diameter.
(VDI 2083: Blatt 4: 1996 Düsseldorf)
Solid or liquid object with defined physical borders and a particle size of at least 0,1µm, but no more than 5µm (VDI 2083: Blatt 1: 2003-06 Düsseldorf)
Microparticle with defined physical boundaries. (as defined in ISO 14644-5) (VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Defined according most standards as an object of solid or liquid composition, or both, of a certain size. US Federal Standard 209 E specifies a size between 0.001 and 1.000µm. ISO 14644 defines a particle as a minute piece of matter with defined physical boundaries (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Particle concentration
The number of individual particles per unit volume of air. (Federal Standard 209D, Stuttgart 1991)
Number of individual particles per unit volume of air (ISO 14644-1:1999 (E))
The number of individual particles per unit volume of air (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Particle emission
Release of particles from a consumable under specified load
Note 1: All emitted particles released during typical use are considered. Therefore, unlike the particle emission behaviour of equipment (VDI 2083 Part 9.1) and materials (VDI 2083 Part 17), the particle emission behaviour of consumables is also influenced by the particle load condition.
Note 2: The following distinction can be made when measuring particle emissions from consumables:
– Immediately prior to the particle emission measurement, the particles are generated due to a typical load.
– Particles have been carried over due to an earlier particle sedimentation process.
– Surfaces from which particles are emitted have not been cleaned properly.
(VDI 2083: Blatt 9.2: 2017-01 Düsseldorf)
Particle emission behaviour
Quantitative characterisation of the particulate emission from a material (3.1) under specified load. (VDI 2083: Blatt 17: 2013-06 Düsseldorf)
Particle size
The apparent maximum linear dimension of a particle in the plane of observation as seen with a microscope, or the equivalent diameter of a particle detected by automatic instrumentation. The equivalent diameter is the diameter of a reference sphere having known properties and producing the same responses in the sensing instrument as the particle being measured. (Federal Standard 209D, Stuttgart 1991)
Diameter of a sphere that produces a response, by a given particle-sizing instrument, that is equivalent to the response produced by the particle being measured
NOTE For discrete-particle-counting, light-scattering instruments, the equivalent optical diameter is used (ISO 14644-1:1999 (E))
The maximum linear dimension of a reference which is usually described by the equivalent diameter.
The equivalent diameter is the diameter of a reference sphere having known properties and producing the same response in the Instrument used as the particle being measured.
NOTE: Different measurement methods produce different equivalent diameters.
(VDI 2083: Blatt 4: 1996 Düsseldorf)
Diameter of any particle, determined by comparison with defined reference particles (VDI 2083: Blatt 1: 2003-06 Düsseldorf)
The apparent maximum linear dimension of a particle in the plane of observation as seen with a microscope or the equivalent diameter of a particle detected by automatic instrumentation. (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Particle size distribution
Cumulative distribution of particle concentration as a function of particle size (ISO 14644-1:1999 (E))
Distribution of cumulative frequency of particle concentration as a function of particle diameter (VDI 2083: Blatt 1: 2003-06 Düsseldorf)
Particulate contamination
Particles having the potential to affect the process, the product, the personnel or the facilities.
Note 1: The principal way for particles to settle on surfaces is by deposition. Deposition processes are primarily driven by physical effects such as gravitation, electrostatic attraction, diffusion, thermophoresis or a combination of these.
Note 2: Particulate contaminations may be generated by reactive, chemical processes such as corrosion or abrasion of a surface.
(VDI 2083: Blatt 9.1: 2006-12 Düsseldorf)
Particulate percent area coverage
The fraction of the surface that is covered by particles, reported as total particle projected area divided by total surface area. (Military Standard Product Cleanliness Levels and Contamination Control Program MIL-STD-1246C, 11. April 1994)
passive minienvironment (passive ME)
ME which protects the product by means of an enclosure isolation it from the environment (VDI 2083: Blatt 16.2: 2021-04 Düsseldorf)
Pasteurization
The process of heating milk or other liquids to a moderate temperature for a specified period of time. This exposure kills most species of pathogenic bacteria and significantly retards the development of others (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Pathogen
Any disease producing microorganism or material. (Introduction to Contamination Control and Cleanroom Technology, 1999)
Pathogenic
Giving origin to disease or to morbid symptoms (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Percentage of the theoretical (stoichiometric)
quantity (theoretical percentage)
Percentage of the theoretically required quantity of chemicals (100% is the stoichiometrically required quality) used for the regeneration of ion exchangers. As a rule, leaner-than-stoichiometric quantities are used (in excess of 100%)
(VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Performance qualification (PQ, also: clearance for production)
A series of tests and measurements shall be carried out in order to demonstrate compliance of the cleanroom installation with the specified design parameters, taking into account the personnel and the specified processes or activities in the occupancy state “in operation” (see also VDI 2083 Part 5.1). (VDI 2083: Blatt 4.1: 2006-10 Düsseldorf)
Permeate
That part of the feed in a membrane system which passes the membrane. (VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Personal filter
A simple way of expressing a clothing system for cleanroom use. (Introduction to Contamination Control and Cleanroom Technology, 1999)
Physical contamination
Interference with the process, the product, the personnel or the facilities caused by physical factors such as humidity, temperature, vibration, electrostatic and electromagnetic fields. (VDI 2083: Blatt 9.1: 2006-12 Düsseldorf)
Physisorption
The removal of specific substances (here AMC) by way of physical adhesion to the active surface of the sorbent and bonding by weak interaction, cf. ->chemisorption.
Note: Unlike chemisorption, physisorption is reversible.
(VDI 2083: Blatt 9.2: 2009-07 Düsseldorf)
Planning qualification
An integral planning test for complying with the requirements laid down in the technical specifications (planning objectives), performed by an authority independent of the project organization. (VDI 2083: Blatt 12: 2000-01 Düsseldorf)
PO
purchase order (SEMI E137-0705, guide for final assembly, packaging, transportation, unpacking and relocation of semiconductor manufacturing equipment, 2004)
POC
Point of connection (SEMI F42-0600, test mtehod for semiconductor processing equipment voltage sag immunity, 1999)
Pod
A box having a Standard Mechanical Interface (SMIF). (SEMI E44-96, Guide for Procurement and acceptance of minienvironments, 1995)
Point of connection (POC)
Distributer of a distribution system, e.g. outlet valve of an ultrapure-water submain or of the equipment hook-up. (VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Point of contact
A designated individual position in an organization, the occupant of which has the responsibility for assuring that contractual contamination control requirements are met. This position is identified and serves as a focal point for all activities concerning contamination control. (Military Standard Product Cleanliness Levels and Contamination Control Program MIL-STD-1246C, 11. April 1994)
Point of distribution (POD)
Point of hand-over from the production plant. (VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Point of entry (POE)
Entry at the consumer, e.g. inlet valve of the internal distribution in a wet etch bench. (VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Point of supply (POS)
Point of media supply; here: exit of ultrapure-water production. (VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Point of use (POU)
The point where a particular activity is carried out. Typically the final filter of a ventilation system is point of use, i.e. the filter is an integrated part of the roof. (Introduction to Contamination Control and Cleanroom Technology, 1999)
Actual consumer (introduction into the process), e.g. water quench in a wet etch bench. (as defined in VDI 2083 Part 10) (VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
zone within which specified parameters shall be complied with (VDI 2083: Blatt 16.2: 2021-04 Düsseldorf)
Positive ventilation
Ventilation pattern where a positive flow of air or other gas is used to purge the room or zone of containments. (Introduction to Contamination Control and Cleanroom Technology, 1999)
pre-acceptance test (initial acceptance)
qualitative and quantitative verification of the specified parameters and/or acceptance criteria of an ME at the contractor’s site after manufacture (VDI 2083: Blatt 16.2: 2021-04 Düsseldorf)
Pre-filter
A filter unit positioned in front of any other filter, used to reduce blockage of the main filter caused by containments. The pre-filter has in general a lower removal rating than the main filter. (Introduction to Contamination Control and Cleanroom Technology, 1999)
Air filter fitted upstream of another filter to reduce the challenge on that filter (ISO 14644-4:2001 (E))
Present Engineering Classes
These Classes are used mainly in rooms where electronic and engineering items are manufactured. Most of these standards are based on one of the various of the US Federal Standard 209.
Some countries completely adopted FS 209, while others made their own national version, similar to FS 209. Some made minor changes of the classes to comply with the metric system, but all changed the denomination of the classes.
Major national standards
Country
|
Standard
|
Year
|
Description
|
Australia |
AS 1386
|
1989 |
Cleanroom and clean work stations |
France |
AFNOR X44101 |
1981 |
Definition of cleanroom levels |
Germany |
VDI 2083.3 |
1993 |
Contamination control measuring technique for clean air rooms |
Holland |
VCCN 1 |
1992 |
Dust and microorganism classification of air |
Japan |
JIS-B-9920 |
1989 |
Measuring methods for airborne particles in cleanroom and evaluating methods, etc. |
Russia |
Gost-R 50766 |
1995 |
Cleanroom classification, general requirements |
UK |
BS 5295 |
1989 |
Environmental cleanliness in enclosed spaces |
US |
FS 209E |
1992 |
Airborne particulate cleanliness and clean zones |
A comparison of major engineering cleanroom classes in the world
USA 209E 1992 |
|
ISO 14644-1 1997 |
Japan B 9920 1989 |
France X44101 1981 |
Germany VDI 2083 1990 |
UK BS 5295 1989 |
Australia AS 1386 1989 |
|
|
|
ISO Class 1 |
1 |
|
|
|
|
|
|
||||||||
|
ISO Class 2 |
2 |
|
0 |
|
|
||
M1 |
||||||||
1 |
ISO Class 3 |
3 |
|
1 |
C |
0,035 |
||
M2 |
||||||||
10 |
ISO Class 4 |
4 |
|
2 |
D |
0,35 |
||
M3 |
||||||||
100 |
ISO Class 5 |
5 |
4,000 |
3 |
E, F |
3,5 |
||
M4 |
||||||||
1,000 |
ISO Class 6 |
6 |
– |
4 |
G, H |
35 |
||
M5 |
||||||||
10,000 |
ISO Class 7 |
7 |
40,0000 |
5 |
J |
350 |
||
M6 |
||||||||
100,000 |
ISO Class 8 |
8 |
4,000,000 |
6 |
K |
3500 |
||
M7 |
||||||||
|
ISO Class 9 |
|
|
7 |
L |
|
||
|
|
Note: The M values for FS 209E (and the ISO values) are in metric units. The M figures are therefore elevated above the line of the others, which are given in cubic feet. FS 209E class 100 therefore corresponds to M class 3.5 and ISO 5.
(Cleanroom Technology / Fundament of Cleanroom Technology, FESTO AG & Co., Ruiter Strasse 82, 73734 Esslingen; Festo Singapore: Jiang Hong, Christian Burdin, Edward Gasper, Festo Germany: Robert Strommer)
Prevention of pollution
use of processes, practices, techniques, materials, products, services or energy to avoid, reduce or control (separately or in combination) the creation, emission or discharge of any type of pollutant or waste, in order to reduce adverse environmental impacts (International Standard, ISO/FDIS 14001, 2004)
Preventive action
action to eliminate the cause of a potential nonconformity (International Standard, ISO/FDIS 14001, 2004)
Procedure
specified way to carry out an activity or a process (International Standard, ISO/FDIS 14001, 2004)
Process core
Location at which the process and the interaction between the environment and the process occurs (ISO 14644-4:2001 (E))
Product
Result of activities or processes; a product may be a manufactured item or a service. (VDI 2083: Blatt 11: 2008-01 Düsseldorf)
production facility
process tool, process machine, production equipment (VDI 2083: Blatt 16.2: 2021-04 Düsseldorf)
Product space of a piece of equipment
Three-dimensional geometrical space containing the volume in which the product is handled. (VDI 2083: Blatt 9.1: 2006-12 Düsseldorf)
Protection factor
The protection factor is the ratio of emission to exposure for the respective type of protection (see also Figure 3).
The protection factor shall be related to the type of protection:
-person-related,
-product-related,
environment-related or
-combinations of the above
(VDI 2083: Blatt 16.1: 2010-08 Düsseldorf)
Protozoa
A major group of microorganisms comprising the simplest forms of life in the animal kingdom (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
PTFE
Polytetrafluoroethylene (ECSS-Q-ST-70-05C, 2009)
PWP
Particles per wafer pass (SEMI E44-96, Guide for Procurement and acceptance of minienvironments, 1995)
Pyrogen
In the medical domain, pyrogens are substance that can induce fever when administered parenterally. This includes (bacterial endotoxin) as well as particles (Section 3.6, e.g. rubber abraded from injection bottles, microscopic plastic particles). (VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
A substance that causes fever (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
QCM
quartz crystal microbalance (ECSS-Q-ST-70-05C, 2009)
Qualification
Working process in accordance with defined procedures, serving to determine and/or verify the performance of a cleanroom installation or a part thereof. (VDI 2083: Blatt 4.1: 2006-10 Düsseldorf)
Documented process of demonstration that
- a production unit,
- an installation or a unit,
- an activity,
- a process,
- a product,
- an organisation, or
- a combination of the aforementioned
is capable of meeting the specified requirements.
Note: In addition to the term “qualification”, the them “validation” is used in the field of pharmaceutics; in this field, the term “validation” subsumes, among other things, all activities verifying the suitability of processes.
(VDI 2083: Blatt 5.1: 2007-09 Düsseldorf)
Prospective definition and checking of systems, subassemblies, components and materials with the objective of proper functioning and achieving the expected results. (VDI 2083: Blatt 11: 2008-01 Düsseldorf)
Qualitative
A term used in relation to quality (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Quality
Degree to which a set of inherent characteristics fulfils requirements. (ISO 9000: 2000)
Note 1: The term “quality” can be used with adjectives such as poor, good or excellent.
Note 2: “Inherent”, as opposed to “assigned”, means existing in something, especially as a permanent characteristic.
(VDI 2083: Blatt 11: 2008-01 Düsseldorf)
Quality inspection
Establishing to what degree an item fulfils a specified quality requirement. (DIN 55350-17)
Note 1: Quality inspections are performed on the basis of inspection characteristics. It must be specified which characteristics the quality inspection refers to and which stage of implementation of the quality requirement is relevant.
Note 2: Quality inspections may be performed at any time and any site, e.g. referred to each stage of the quality cycle. The term “inspection”, “countercheck”, “preliminary check”, “check”, “compliance test” and “confirmation test” are often used as synonyms for “quality inspection”, althougt in a limited sense. These terms should, therefore, be avoided, or the definition applying to the respective application should be specified.
Note 3: Above definition and notes are based on DIN 55350-17
Note 4: The quality inspection may refer to one of the items below:
-material product,
-immaterial product,
-combination of material and immaterial products,
-activity or process
(VDI 2083: Blatt 11: 2008-01 Düsseldorf)
Quantitative
A term used in relation to the measurement of quantity (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Raw water
The water fed into the ultrapure-water plant. (VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
RCS
Reuter Centrifugal Sampler (Introduction to Contamination Control and Cleanroom Technology, 1999)
re-acceptance test
repeated verification or check of the results recorded during the acceptance test (e.g. annually or after recommissioning) (VDI 2083: Blatt 16.2: 2021-04 Düsseldorf)
Reclaim
Process of returning water from production for reuse; with or without treatment, depending on the level of contamination. Exception: production of ultrapure water. (VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Recycling
Process of returning water from production to the ultrapure-water plant; with or without treatment, depending on the level of contamination. (VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Regeneration effluent
The contaminated water obtained from regeneration of exhausted ion exchangers. (based on DIN 25416-2) (VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Regulated operation
(operation in a regulated environment)
Operation of a system subject to legal stipulations.
Note: As an example, consider the operation of a GMP-regulated pharmaceutical plant.
(VDI 2083: Blatt 3.1: 2012-06 Düsseldorf)
Rejection rate (R)
Mean percentage of the undissolved particles and of the ionic and molecular (organic) substances removed by the membrane.
R = (1 – CP/Cf) x 100
where
Cf feed solution concentration of the substance considered
CP filtrate or permeate solution concentration of the substance considered
The rejection rate depends on the operating conditions as well as on the type of the membrane used. (based on EN 14652)
(VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Requalification
Execution of the test sequence specified for the installation to demonstrate compliance with ISO 14644-1 according to the classification of the installation, including the verification of the selected pre-test conditions (ISO 14644-2_2000 (E))
Performance of qualification activities activities at specified intervals and after substantial changes to the processes or subsystems. (VDI 2083: Blatt 5.1: 2007-09 Düsseldorf)
Reuse
Process of returning water from production for reuse and for the production of ultrapure water; with or without treatment, depending on the level of contamination.
Note: Reuse = recycling + reclaim
(VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Resistance to earth
Electrical resistance between an electrode on the surface (3.5) of the material and the grounding point of the material (3.1), when the latter is at a potential of 0 V (“ground”). (VDI 2083: Blatt 17: 2013-06 Düsseldorf)
Resistivity
Capability of dissipating any existing charge in a controlled manner and sufficiently raoidly.
Note: The conductivity of a material depends on its resistivity: the higher the resistivity, the lower the conductive or static dissipative and insulating materials (3.4).
(VDI 2083: Blatt 17: 2013-06 Düsseldorf)
RI
refractive index (ECSS-Q-ST-70-05C, 2009)
Risk
Probability of occurrence of a hazard causing harm and the degree of severity of the harm. (VDI 2083: Blatt 18: 2012-01 Düsseldorf)
Risk analysis
Use of available information to identify hazards and to estimate the risk. [DIN EN 764-7] (VDI 2083: Blatt 18: 2012-01 Düsseldorf)
RODAC plate
A form of contact plate. (Introduction to Contamination Control and Cleanroom Technology, 1999)
RP
Recommended Practices, a series of documents published by the Institute of Environmental Sciences and Technologies (IEST) USA. (Introduction to Contamination Control and Cleanroom Technology, 1999)
Salt passage
Percentage of salts passing through a separating membrane, expressed in terms of the ratio of concentration of salt on the permeate side of the membrane relative to the concentration of salt in the feedwater. (VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Sampling
Passive or active capture or collection of a representative portion of the whole of a biocontamination. (VDI 2083: Blatt 18: 2012-01 Düsseldorf)
Sanitizing
Activity (activities) carried out to properly keep a system in good hygienic condition, comprising cleaning and, possibly, the use of disinfection methods and disinfectants as well as appropriate rinsing. (based on EN 15161) (VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Saturation index (SI)
Logarithm of the ratio of the product of the ion activities of calcium and carbonate over the solubility product of calcite under the prevailing thermodynamic conditions. (as defined in DIN 51009; based on DIN 38404-10)
Note: The auxiliary quantity SI can be used to describe the calcite saturation of water.
SI < 0: Calcite will dissolve in the water
SI = 0: The water is at calcite equilibrium
SI > 0: Calcite will precipitate from the water
(VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Scaling on membranes
Deposition of hardly soluble salts (such as CaCO3, CaSO4) on a membrane, due to an excess of solubility product arising during concentration. (VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
SD module, separative device
Device using dynamic effects to create a safe cascade of separation between the interior and exterior of a defined volume. (VDI 2083: Blatt 9.2: 2009-07 Düsseldorf)
Separation efficiency
separation efficiency= ((c roh -c rein)/c roh)x 100
where
c roh crude-air concentration of a specific substance (->AMC)
c rein clean-air concentration of a specific substance (AMC)
Note 1: The separation efficiency depends on the filter load; it is thus a function of time.
Note 2: The term “efficiency“ is a term adopted from particle filtration; it is not used in this guideline.
Note 3: The separation efficiency is expressed as a percentage.
(VDI 2083: Blatt 9.2: 2009-07 Düsseldorf)
Settle plate
Appropriate vessel (such as a petri dish) of adequate size with a suitable, sterile nutrient medium, left uncovered for a specified time to collect viable particles from the air.
[DIN EN ISO 14698-1]
(VDI 2083: Blatt 18: 2012-01 Düsseldorf)
Significant surface
Any surface of an item or product which is required to meet established cleanliness level requirements. (Military Standard Product Cleanliness Levels and Contamination Control Program MIL-STD-1246C, 11. April 1994)
Silt density index (SDI, Plugging factor PF)
Ratio of the times required to filter a given volume of water (500ml) through a 0,45µm pore size membrane under a constant pressure (2 bar pe) in percent per minute, measured before and after a constant filter test time of T=15min as a function of this test time. (as defined in ASTM D 4189)
Note: The SDI is a measure of the contamination of water with colloid-disperse substances.
(VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Slit sampler
An impaction sampler for microbial analysis in which airborne particles are collected onto a slowly rotating agar plate making it possible to obtain the microbiological profile of a facility as a function of time. The impact forces in such an apparatus are obtained by allowing the air to be analysed to pass through a very fine slit. (Introduction to Contamination Control and Cleanroom Technology, 1999)
SLS
Stray Light Sensor (SEMI E54.10-0600, Specification for sensor/actuator network specific device model for an in-situ particle monitor device, 2000)
SMIF
Standard mechanical interface (SEMI E44-96, Guide for Procurement and acceptance of minienvironments, 1995)
SMIF-Pod (standard mechanical interface pod)
ME with a standardised interface pod)
ME with a standardised mechanical interface (opening and connecting mechanism) for automated opening without human intervention. (VDI 2083: Blatt 16.2: 2021-04 Düsseldorf)
SPC
statistical process control (VDI 2083: Blatt 10: 1998-02 Düsseldorf)
Specific area
Diameter of the infrared beam at the window location (ECSS-Q-ST-70-05C, 2009)
Specification
Document stating requirements. [ISO 9000: 2000]
Note: A specification can be related to activities (e.g. procedure document, process specification and test specification), or products (e.g. product specification, performance specification and drawing).
(VDI 2083: Blatt 11: 2008-01 Düsseldorf)
Spore
A subcellular body produced by some species of bacteria which is considerably more resistant to harsh conditions such as heat, disinfectants and radiation, than the vegetative form (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
S/N
signal or noise ratio (ECSS-Q-ST-70-05C, 2009)
Softening
Reduction of water hardness by exchanging the alkaline-earth ions (primarily calcium and magnesium) with sodium ions. This is accomplished by directing the flow of water over a bed of cation-exchange-resin beads in which the cations are available in the form of sodium (as defined in EN 14743) (VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Sorption
Generic term for the enrichment of a substance in the boundary region between different phases (e.g. -> absorption, -> adsorption, ->desorption). Sorption will occur predominantly at liquid-solid and gassolid interfaces. (VDI 2083: Blatt 9.2: 2009-07 Düsseldorf)
Enrichment of a substance in the boundary region between different phases (e.g. absorption, adsorption, desorption).
Note: sorption will occur predominantly at liquid-solid and gas-solid interfaces.
(VDI 2083: Blatt 8.1: 2014-10 Düsseldorf)
Sorption kinetics
Time variation of -> sorption until equilibrium is attained. (VDI 2083: Blatt 9.2: 2009-07 Düsseldorf)
Start-up
Act of preparing and bringing an installation into active service, including all systems
EXAMPLE Systems may include procedures, training requirements, infrastructure, support services, statutory undertakings requirements.
(ISO 14644-4:2001 (E))
Preparation and commissioning of a cleanroom installation including all systems, following the execution of a construction activity. All procedures and requirements relevant to the functioning of a system, such as documentation, training and the operation of auxiliary equipment, are covered. (VDI 2083: Blatt 4.1: 2006-10 Düsseldorf)
Static conductive
Property of a material allowing electrostatic charge to dissipate very rapidly across its surface and/or through its volume (VDI 2083: Blatt 9.2: 2017-01 Düsseldorf)
Static conductive material
Material allowing an electrostatic charge to dissipate very rapidly on its surface (3.5) and/or through its volume. (VDI 2083: Blatt 17: 2013-06 Düsseldorf)
Static dissipative
Property of a material allowing an electrostatic charge to dissipate across its surface and/or through its volume within a period of time that is short compared to the time within which said charge is generated or the time within which said charge can cause an electrostatic problem
(VDI 2083: Blatt 9.2: 2017-01 Düsseldorf)
Static dissipative material
Material allowing an electrostatic charge to dissipate on its surface (3.5) and/or through its volume, within a period of time that is short compared to the time within which said charge is generated or can cause an electrostatic problem.
Note: Floorings, for instance, are classified as static dissipative according to DIN EN 14041 if their volume resistance measured to DIN EN 1081 is 109 Ω or less.
(VDI 2083: Blatt 17: 2013-06 Düsseldorf)
Stationary phase
The stage in the growth pattern of microorganisms where the number of new cells formed is equal to the number of cells that die (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Step-over bench
Bench that is used when changing cleanroom clothing and which provides a barrier to the spread of floor contamination. (Introduction to Contamination Control and Cleanroom Technology, 1999)
Sterile
Cleanliness defintion (Introduction to Contamination Control and Cleanroom Technology, 1999)
Cleanliness definition. Different definition can be recognised: Free from living organisms or free from living microorganisms (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Sterilization
Any process or activity leading to the complete elimination of microbial activity. (Introduction to Contamination Control and Cleanroom Technology, 1999)
Process which eliminates all forms of viable microorganisms from a product. (based on ISO 14160) (VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Total elimination of biological entities capable of reproduction. (VDI 2083: Blatt 16.1: 2010-08 Düsseldorf)
Process of inactivation of all microorganisms and all relevant microbial spores. [DIN EN ISO 14159] (VDI 2083: Blatt 18: 2012-01 Düsseldorf)
Surface
This Guideline applies to all surfaces which
- face the clean area and / or
- are in contact with the cleanroom product
Textiles and other porous materials have no defined closed surface. Particles and other contamination are also emitted from within the material.
(VDI 2083: Blatt 4: 1996 Düsseldorf)
For the purposes of this guideline, the term “surface” denotes any surface
-facing the controlled environment,
-being located within the controlled environment and/or
-coming into contact with the product.
(VDI 2083: Blatt 9.1: 2006-12 Düsseldorf)
Any area
-facing the controlled environment,
-being located within the controlled environment, and/or
-coming into contact with the product
(VDI 2083: Blatt 9.1: 2021-01 Düsseldorf)
All surfaces which
-are related within the controlled area and/or
-come into contact with the product manufactured.
(VDI 2083: Blatt 17: 2013-06 Düsseldorf)
Surface characteristics
Characteristics which are of importance in view of the surface cleanliness (such as roughness, surface conductivity, cleanability, accessibility, waviness) (VDI 2083: Blatt 9.1: 2006-12 Düsseldorf)
Characteristics relevant to surface cleanliness (such as roughness, conductivity, cleanability, accessibility, waviness). (VDI 2083: Blatt 17: 2013-06 Düsseldorf)
Surface chemical contamination
Substance on the surface which, owing to its physical and/or the product, the process, the installation and/or the personnel. (VDI 2083: Blatt 9.2: 2009-07 Düsseldorf)
Molecular (chemical, non-particulate) deposits on the surface (3.5) of a material (3.1), which may have a deleterious effect on humans, the product, process, environment or equipment. [VDI 2083 Blatt 8.1, DIN EN ISO 14644-6]
Note: Surface chemical contamination can be caused by, e.g. AMC and can cause AMC.
(VDI 2083: Blatt 17: 2013-06 Düsseldorf)
Surface cleanliness
Surface cleanliness as defined by this Guideline is the absence of such particulate and non-particulate contamination which affect the process or the product. It is possible that particulate contamination is converted to non-particulate contamination, and vice versa. The definition of a clean surface as given by this Guideline includes its suitability for the intended use, which is determined by specified physical, chemical and constructional properties. (VDI 2083: Blatt 4: 1996 Düsseldorf)
For the purposes of this guideline, surface cleanliness denotes the absence of particulate contaminations which might affect the process, the product, the personnel or the facilities. (VDI 2083: Blatt 9.1: 2006-12 Düsseldorf)
Absence of particulate contaminations (VDI 2083: Blatt 9.1: 2021-01 Düsseldorf)
Surface cleanliness class (particulate) (SCC)
Number of individual particles on a reference surface area of I cm², referred to a reference particle size of 1µm, in a decimal evaluation system. (VDI 2083: Blatt 9.1: 2006-12 Düsseldorf)
Surface electric potential
Isolated patches of positive or negative charge on the surface of the workplace or the product give rise to a difference in potential between these charges. The surface electric potential is a voltage which can be indicated by suitable measuring instruments (such as teraohm meters or field-strength meters). (VDI 2083: Blatt 9.1: 2006-12 Düsseldorf)
Surface molecular contamination (SMC)
Presence on the surface of a product or analytical instrument of molecular (chemical, non-particulate) species in the sorbed state which may have a deleterious effect on the product, process or equipment in the cleanroom or controlled environment (ISO 14644-8: 2003-09)
Surface particle cleanliness
Absence of particulate contaminants that can affect the process, product, personnel or facilities (VDI 2083: Blatt 9.2: 2017-01 Düsseldorf)
Surface particle cleanliness by particle concentration class (SPC; SP class)
Classification in terms of the number of individual particles on a reference surface area, referenced on a reference particle diameter
Note: The reference surface area is 1 cm² as per VDI 2083 Part 9.1 or 1 m² as per DIN EN ISO 14 644-9. The regulation used as a basis in the particular case shall be stated.
(VDI 2083: Blatt 9.2: 2017-01 Düsseldorf)
Surface resistance
Electrical resistance, measured between two electrodes placed on a surface (such as, in the case of this guideline, a floor covering; EN 1081). (VDI 2083: Blatt 9.1: 2006-12 Düsseldorf)
Surface resistivity
Electrical resistance measured between two electrodes on a surface (VDI 2083: Blatt 9.2: 2017-01 Düsseldorf)
Surrounding area
Area outside the associated controlled environment, including the outside of the airlocks for material and personnel. (VDI 2083: Blatt 9.1: 2006-12 Düsseldorf)
SVOC (semi-volatile organic compounds)
Volatile organic compounds in the retention range >n-hexadecane C16 (VDI 2083: Blatt 17: 2013-06 Düsseldorf)
System space of a piece of equipment
The system space of a piece of equipment comprises the entire three-dimensional geometrical space of a piece of equipment. (VDI 2083: Blatt 9.1: 2006-12 Düsseldorf)
Entire three-dimensional geometrical space of a piece of equipment (VDI 2083: Blatt 9.1: 2021-01 Düsseldorf)
System volume of an operating material
The system volume of an operating material covers the complete geometrical, three-dimensional extent of an operating material. (VDI 2083: Blatt 8: 2002-09 Düsseldorf)
Technical specifications (performance specification)
Compilation of all customer requirements (delineation) and the contractor’s services (performance specification) with regard to the scope of supply and performance. (based on VDI/VDE 3694) (VDI 2083: Blatt 12: 2000-01 Düsseldorf)
Tenside
Surfactant. An agent, both hydrophobic as well as hydrophilic in nature. Used for cleaning purposes as it can be used to dissolve fats and make them water-soluble. (Introduction to Contamination Control and Cleanroom Technology, 1999)
Terminal filter
Filter installed immediately upstream of the duct end (where the air is discharged into the cleanroom).
Note: ISO 16444 uses the term “terminal filter” for all suitable filters. As examples, this standard lists HEPA (High Efficiency Particulate Air) and ULPA (Ultra Low Penetration Air) filters where these are installed in a terminal position upstream of where the air is discharged into the cleanroom.
(VDI 2083: Blatt 4.1: 2006-10 Düsseldorf)
Test
Procedure undertaken in accordance with a defined method to determine the performance of an installation or an element thereof (ISO 14644-2:2000 (E))
Test contamination (tracing unit)
Substance with or without microorganisms, which serves to determine the success of cleaning or disinfection. (VDI 2083: Blatt 18: 2012-01 Düsseldorf)
Test method
The overall process from sampling up to the interpretation and documentation. (VDI 2083: Blatt 9.2: 2009-07 Düsseldorf)
Overall process starting with sampling and ending with the interpretation of the results and documentation. (VDI 2083: Blatt 18: 2012-01 Düsseldorf)
Thermodesorption
Thermally induced release of volatile substances from a carrier material.
Note: See also procedure IEST WG 31.
(VDI 2083: Blatt 17: 2013-06 Düsseldorf)
TOC
Total organic carbon (SEMI E137-0705, guide for final assembly, packaging, transportation, unpacking and relocation of semiconductor manufacturing equipment, 2004)
Total capacity
Mass of a specific substance for 100% breakthrough. (VDI 2083: Blatt 8.1: 2014-10 Düsseldorf)
Total cell count
Number of all microbial cells (bacteria, algae, moulds, etc.) referred to a specified volume, mass or surface of a sample.
Note: Bacteria counts are mostly achieved by applying a DNA-specific marker dye, e.g. acridine-orange or DAPI, and subsequent counting by means of microscopic processes. The total cell count determines all cells without allowing statements as to their activity or vitality.
(VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Total hardness
Concentration of the alkaline-earth ions (mainly calcium and magnesium) present in water. (as defined in EN 14743) (VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Total Mass Loss (TML)
The mass that outgases from a material, as specified in ASTM E595, expressed as a percentage of the initial mass of the specimen. (Military Standard Product Cleanliness Levels and Contamination Control Program MIL-STD-1246C, 11. April 1994)
Toxin
A poison. The term is frequently used to refer specifically to a protein product (or other biomolecule) produced by some higher plants, certain animals and pathogenic bacteria, which is highly toxic to other living organisms (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Touch plates
Agar plates used for detecting the presence of microbial contaminants on hands. These sterile dishes are often used by operators engaged in aseptic filling (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Tribo-electric charging
Generation of electric charges by rubbing or separating two surfaces (see EN 61340-5-l and EN 61340-5-2). (VDI 2083: Blatt 9.1: 2006-12 Düsseldorf)
t90-time
The time elapsing between the beginning of the measurement and that point in time when the indication is 90% of the final value (final concentration). (VDI 2083: Blatt 9.2: 2009-07 Düsseldorf)
Time elapsing between the beginning of the measurement and that point in time when the indication is 90% of the final value (final concentration).
Note: In case of first-time measurements and/or changes to the installation, the t90 time specific for the substance in question must be determined and specified. It is recommended to verify and document the t90 time at regular intervals.
(VDI 2083: Blatt 8.1: 2014-10 Düsseldorf)
Turbidity
Reduction in transparency of a liquid, due to the presence of non-dissolved substances. It is expressed in FTU (or NTU in the USA). (as defined in ISO 7027) (VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
The cloudiness of a liquid caused by the presence of finely divided suspended material. (Military Standard Product Cleanliness Levels and Contamination Control Program MIL-STD-1246C, 11. April 1994)
Turbulent induction flow
Air distribution where the supply air entering the controlled environment blends with the air in the room through induction (ISO 14644-l). (VDI 2083: Blatt 9.1: 2006-12 Düsseldorf)
Air distribution where the supply air entering the cleanroom or clean zone mixes with internal air by means of induction
[DIN EN ISO 14644-1, 3.2.8, non-unidirectional airflow]
(VDI 2083: Blatt 9.1: 2021-01 Düsseldorf)
TVOC (total volatile organic compounds)
Total of all volatile organic compounds in the retention range between n-hexane C6 and n-hexadecane C16. (VDI 2083: Blatt 17: 2013-06 Düsseldorf)
TXRF
Total reflection x-ray fluorescence spectroscopy (SEMI E44-96, Guide for Procurement and acceptance of minienvironments, 1995)
Cleanroom technology terms from U to Z
U descriptor
The maximum allowable concentration (particles per cubic meter of air) of ultrafine particles. The U descriptor serves as an upper confidence limit or as the upper limit for the location averages, or both, as appropriate, U descriptors are independent of airborne particulates cleanliness classes, and may be specified alone or in conjunction with one or more airborne particulate cleanliness classes. (Federal Standard 209D, Stuttgart 1991)
UDF
Unidirectional Flow. New term replacing LAF. UDF is an airflow which has a single flow direction and may or may not contain uniform velocities of airflow. UDF results in quick, directed transport of particles out of the clean zone. (Introduction to Contamination Control and Cleanroom Technology, 1999)
ULPA
Ultra Low Penetrating Air Filter. An ULPA filter is defined as a filter for ventilation air with the ability to reduce the number of particles in the air of size 0.12 µm and greater, by at least 99.999 % as measured with DOP aerosol. (Introduction to Contamination Control and Cleanroom Technology, 1999)
Ultrafine particles
Particles in the size range from approximately 0.02 µm to the upper limit of detecability of the DPC described in Appendix D. Ultrafine particles are operationally defined by the relationship for counting efficiency vs. particle size of Appendix D. (Federal Standard 209D, Stuttgart 1991)
Particles in the size range from approximately 0.01 µm to the upper detection limit of the DPC. (Introduction to Contamination Control and Cleanroom Technology, 1999)
Particle with an equivalent diameter less than 0,1 µm (ISO 14644-1:1999 (E))
Particle whose equivalent diameter is less than o,1µm (VDI 2083: Blatt 1: 2003-06 Düsseldorf)
Ultrapure water
Water from which interfering contaminants (particle, organic, biological, ionic and other contaminants) have been removed to a predefined, high degree of purity. (VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Unilateral flow
Controlled airflow with uniform velocity and almost parallel streamlines over the entire cross section of the controlled environment (ISO 14644-l).
Note: Such a flow affords a directed transport or particles, usually out of the controlled environment.
(VDI 2083: Blatt 9.1: 2006-12 Düsseldorf)
Controlled airflow through the entire cross-section of a cleanroom or a clean zone with a steady velocity and airstreams that are considered to be parallel
[DIN EN ISO 14644-1, 3.2.7, unidirectional airflow]
Note: Such a flow affords a directed transport of particles, usually out of the controlled environment.
(VDI 2083: Blatt 9.1: 2021-01 Düsseldorf)
Unidirectional airflow
Airflow having generally parallel streamlines, operating in a single direction, and with uniform velocity over its cross section; previously referred to as “laminar” airflow. (Federal Standard 209D, Stuttgart 1991)
Controlled airflow through the entire cross-section of a clean zone with a steady velocity and approximately parallel streamlines
NOTE This type of airflow results in a directed transport of particles from the clean zone
(ISO 14644-4:2001 (E))
Upper confidence limit (UCL)
An upper limit of the estimated mean which has been calculated so that, in a specified percentage of cases, its value exceeds the true population mean, both means having been sampled from a normal (Gaussian) distribution. In this Stndard, a 95 % UCL is used. (Federal Standard 209D, Stuttgart 1991)
UPW
Ultrapure water (SEMI E137-0705, guide for final assembly, packaging, transportation, unpacking and relocation of semiconductor manufacturing equipment, 2004)
Usability/ suitability for use
Quality and resistance/durability to the gradual failing, as a consequence of ageing, of characteristics of the surface of a piece of equipment, which are required for usability, or of its wear resistance. (VDI 2083: Blatt 9.1: 2006-12 Düsseldorf)
Quality and resistance/durability to the gradual failing, as a consequence of ageing, of characteristics of the surface of a piece of equipment, which are required for usability, or of its wear resistance
Note: Resistance to ageing is a characteristic inherent to the physico-chemical structure. Resistance to wear is based on the mechanical characteristics of the piece of equipment and can be tested using physical methods.
(VDI 2083: Blatt 9.1: 2021-01 Düsseldorf)
UV
ultraviolet (ECSS-Q-ST-70-05C, 2009)
Validation
Full and detailed documentation that all processes and procedures are functioning in the manner for which they were designed. (Introduction to Contamination Control and Cleanroom Technology, 1999)
Documented confirmation that the requirements of a specified application are met.(VDI 2083 Part 5.1) (VDI 2083: Blatt 3.1: 2012-06 Düsseldorf)
Confirmation, through the provision of objective evidence, that the requirements for a specific intended use or application have been fulfilled. (ISO 900:2000)
Note 1: The term “validated” is used to designate the corresponding status.
Note 2: The use conditions for validation can be real or simulated.
(VDI 2083: Blatt 11: 2008-01 Düsseldorf)
VC
Vibration classification (VC-A – VC-E) (SEMI E44-96, Guide for Procurement and acceptance of minienvironments, 1995)
VCM
volatile condensable material (ECSS-Q-ST-70-05C, 2009)
Verification
The procedure for determining the compliance of air in a cleanroom or clean zone to an airborne particulate cleanliness class limit or a U descriptor, or both, as specified. (Federal Standard 209D, Stuttgart 1991)
Confirmation, through the provision of objective evidence, that specified requirements have been fulfilled. (ISO 9000: 2000)
Note 1: The term “verified” is used to designate the corresponding status.
Note 2: Confirmation can comprise activities such as:
-performing alternative calculations
-comparing a new design specification with a similar proven design specification
-undertaking tests and demonstrations
-reviewing documents prior to issue
(VDI 2083: Blatt 11: 2008-01 Düsseldorf)
Viable
Capable of growing and living. The ability of microorganisms to grow and form visible colonies on an appropriate medium (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Viricide
An agent that kills viruses (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
Virus
A group of minute infectious agents that, with certain exceptions, cannot be visualized with a light microscope. Viruses are characterized by their lack of independent metabolism and canreplicate only within a living host cell (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)
VOC (volatile organic compounds)
Volatile organic compounds in the retention range between n-hexane C6 and n-hexadecane C16 and generic term used to subsume VVOC (3.3), VOC, SVOC (3.3) and TVOC (3.3). (VDI 2083: Blatt 17: 2013-06 Düsseldorf)
Volatile condensable material (VCM)
Gaseous products released from a material under specified conditions of temperature and pressure, that condense at other specified conditions of temperature or pressure or both. (Military Standard Product Cleanliness Levels and Contamination Control Program MIL-STD-1246C, 11. April 1994)
VVOC (very volatile organic compounds)
Highly volatile organic compounds in the retention range < n-hexane C6. (VDI 2083: Blatt 17: 2013-06 Düsseldorf)
VPD
Vapor phase decompostion (SEMI E44-96, Guide for Procurement and acceptance of minienvironments, 1995)
Water hardness
The property resulting from the presence of calcium and magnesium salts and, in special cases, of strontium and/or barium salts. (as defined in EN 12829) (VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Water hardness units and methods of conversion
According to the SI system of units, the content of alkaline-earth ions, i.e. the total hardness is expressed in moles per litre or, considering the low concentration, in millimoles per litre (mmol/l) (see conversion table) (VDI 2083: Blatt 13.1: 2009-01 Düsseldorf)
Wear
Progressive loss of material from the surface (3.5) of a solid body (base body) induced by mechanical causes, i.e. contact and relative motion with a counter body. (VDI 2083: Blatt 17: 2013-06 Düsseldorf)
z-value
The increase in temperature that will improve the destruction rate of microorganisms by a factor of 10. The z-value is used in relation to sterilization in an autoclave (Introduction to Contamination Control and Cleanroom Technology; Dr. Matts Ramstorp, Malmö, 2000; WILEY-VCH Verlag GmbH in Weinheim)