ASTM G121-18

Standard Practice for Preparation of Contaminated Test Coupons for the Evaluation of Cleaning Agents

SIGNIFICANCE AND USE
5.1 This practice will be suitable to direct the preparation of test coupons with a known amount of contaminant on the surface. A standard test coupon is described and a list of contaminants that have typically been found in oxygen-enriched systems and components is provided.  
5.2 These test coupons shall be used in the evaluation of cleaning agents for oxygen-enriched systems and components. This will permit direct comparison within and between test facilities.  
5.3 Materials used in other fluid handling systems such as nitrogen, helium, hydrogen, gasoline, etc. may also be prepared for evaluation by this practice.
SCOPE
1.1 This practice describes the procedure for the preparation of single- and double-sided contaminated test coupons for the evaluation of cleaning agents. It is applicable for the evaluation of cleaning agents proposed for the cleaning of oxygen equipment, pharmaceutical manufacturing equipment, and medical devices (see Test Method G122 and Guide G127). It also is applicable to other systems where contamination is a concern.  
1.2 Several classes of contaminants/residues most likely to be found in oxygen equipment, pharmaceutical manufacturing equipment, and medical devices are identified. However, if the user of this practice has identified contaminants not included in these classes, such identified contaminants may be substituted for the preparation of the test coupons if appropriate for this test method.  
1.3 Solvent and cleaning agent compatibility with nonmetallic substrates should be verified prior to the preparation of the test coupons. Typical nonmetallic materials utilized in oxygen systems are contained in Guide G63.  
1.4 This practice may involve hazardous materials, operations, and equipment. This practice does not purport to address all of the safety concerns associated with its use. It is the responsibility of whomever uses this practice to consult and establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

General Information

• Status: Published
• Publication Date: 30-Nov-2018
• ICS: 71.100.40 - Surface active agents
• Technical Committee: G04 - Compatibility and Sensitivity of Materials in Oxygen Enriched Atmospheres
• Drafting Committee: G04.02 - Recommended Practices

Relations

• Replaces: ASTM G121-98(2015)e1 - Standard Practice for Preparation of Contaminated Test Coupons for the Evaluation of Cleaning Agents
• Effective Date: 01-Dec-2018
• Refers: ASTM E1235-12(2020) - Standard Test Method for Gravimetric Determination of Nonvolatile Residue (NVR) in Environmentally Controlled Areas for Spacecraft
• Effective Date: 01-Apr-2020
• Refers: ASTM F331-13(2020) - Standard Test Method for Nonvolatile Residue of Solvent Extract from Aerospace Components (Using Flash Evaporator)
• Effective Date: 01-Apr-2020
• Refers: ASTM E1235-12(2020)e1 - Standard Test Method for Gravimetric Determination of Nonvolatile Residue (NVR) in Environmentally Controlled Areas for Spacecraft
• Effective Date: 01-Apr-2020
• Refers: ASTM E3106-18 - Standard Guide for Science-Based and Risk-Based Cleaning Process Development and Validation
• Effective Date: 01-Sep-2018
• Refers: ASTM E3106-17 - Standard Guide for Science-Based and Risk-Based Cleaning Process Development and Validation
• Effective Date: 01-Dec-2017
• Refers: ASTM F331-13 - Standard Test Method for Nonvolatile Residue of Solvent Extract from Aerospace Components (Using Flash Evaporator)
• Effective Date: 01-Jun-2013
• Refers: ASTM E1235-12 - Standard Test Method for Gravimetric Determination of Nonvolatile Residue (NVR) in Environmentally Controlled Areas for Spacecraft
• Effective Date: 01-Nov-2012
• Refers: ASTM F303-08 - Standard Practices for Sampling for Particles in Aerospace Fluids and Components
• Effective Date: 01-Nov-2008
• Refers: ASTM F312-08 - Standard Test Methods for Microscopical Sizing and Counting Particles from Aerospace Fluids on Membrane Filters
• Effective Date: 01-Nov-2008
• Refers: ASTM G122-96(2008) - Standard Test Method for Evaluating the Effectiveness of Cleaning Agents
• Effective Date: 01-Sep-2008
• Refers: ASTM E1235-08 - Standard Test Method for Gravimetric Determination of Nonvolatile Residue (NVR) in Environmentally Controlled Areas for Spacecraft
• Effective Date: 01-May-2008
• Refers: ASTM G127-95(2008) - Standard Guide for the Selection of Cleaning Agents for Oxygen Systems
• Effective Date: 01-Apr-2008
• Refers: ASTM G63-99(2007) - Standard Guide for Evaluating Nonmetallic Materials for Oxygen Service
• Effective Date: 15-Mar-2007
• Refers: ASTM D1193-06 - Standard Specification for Reagent Water
• Effective Date: 01-Mar-2006

Overview

ASTM G121-18 - Standard Practice for Preparation of Contaminated Test Coupons for the Evaluation of Cleaning Agents establishes a uniform procedure for contaminating test coupons with a known amount of residue or particle for use in evaluating the effectiveness of cleaning agents. This standard is widely referenced in industries working with oxygen-enriched systems, pharmaceutical manufacturing equipment, and medical devices. By standardizing the preparation of test coupons, ASTM G121-18 ensures repeatability and comparability of cleaning efficacy testing across different facilities and test scenarios.

Key Topics

• Test Coupon Preparation: Guidelines for using single-sided and double-sided metallic coupons that represent actual equipment surfaces, including surface finish and material of construction.
• Contaminant Classes: Identification of residues commonly found in oxygen systems, pharmaceutical, and medical device environments, such as oils, greases, waxes, inks, and pharmaceutical compounds.
• Application Methods: Three documented coupon contamination methods (single side, double side, and both NVR and particulate) based on the physical nature and distribution of the contaminant.
• Measurement and Documentation: Procedures for accurate weighing, drying, and storing of coupons to ensure a defined contamination level, as well as guidance on reporting key parameters like contaminant amount, surface area, and material grade.
• Safety and Compatibility: Emphasis on the safe handling of solvents and contaminants, and the need to verify compatibility of cleaning agents and solvents with non-metallic substrates prior to evaluation.
• Relevance Across Systems: Applicability extends beyond oxygen systems to any critical fluid-handling system where cleanliness is a safety or quality concern, including nitrogen, helium, hydrogen, and petroleum fluids.

Applications

ASTM G121-18 is essential for the following practical scenarios:

• Evaluation of Cleaning Agent Performance: Enables side-by-side and inter-laboratory comparison of various cleaning chemicals by using coupons contaminated with realistic residues.
• Qualification of Cleaning Procedures: Used during commissioning of process equipment and medical devices to demonstrate cleaning effectiveness before use in production or clinical environments.
• Simulation of Real-world Contamination: Allows operators to simulate the accumulation of specific contaminants found in operation, providing data to validate or improve cleaning procedures.
• Support for Quality and Regulatory Compliance: The documented methodology supports audit trails and validation protocols crucial for regulated environments such as pharmaceutical manufacturing and medical device production.
• Dirty Hold Time Studies: Coupons can be held for defined periods between contamination and cleaning, simulating actual delays between process steps.

Related Standards

The preparation and evaluation of contaminated test coupons are supported by additional ASTM and ANSI standards:

• ASTM G122 - Test Method for Evaluating the Effectiveness of Cleaning Agents
• ASTM G127 - Guide for the Selection of Cleaning Agents for Oxygen-Enriched Systems
• ASTM G63 - Guide for Evaluating Nonmetallic Materials for Oxygen Service
• ASTM G94 - Guide for Evaluating Metals for Oxygen Service
• ASTM E1235 - Gravimetric Determination of Nonvolatile Residue (NVR)
• ASTM F312, F303, F331 - Methods related to particle sizing and NVR in aerospace fluids
• ASTM E3106, F3127 - Guides for science-based and risk-based cleaning process development and validation
• ANSI B46.1 - Surface Texture (Surface Roughness, Waviness, and Lay)

Keywords: ASTM G121, test coupon preparation, cleaning agent evaluation, standard test coupon, non-volatile residue, contamination, pharmaceutical equipment cleaning, oxygen system cleaning, medical device cleaning, cleaning validation.

Adopting ASTM G121-18 improves traceability, reliability, and regulatory confidence in cleaning agent assessment and contamination control programs.

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: G121 − 18
Standard Practice for
Preparation of Contaminated Test Coupons for the
Evaluation of Cleaning Agents
This standard is issued under the fixed designation G121; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 2. Referenced Documents
2.1 ASTM Standards:
1.1 This practice describes the procedure for the preparation
D1193 Specification for Reagent Water
of single- and double-sided contaminated test coupons for the
E1235 Test Method for Gravimetric Determination of Non-
evaluationofcleaningagents.Itisapplicablefortheevaluation
volatile Residue (NVR) in Environmentally Controlled
of cleaning agents proposed for the cleaning of oxygen
Areas for Spacecraft
equipment, pharmaceutical manufacturing equipment, and
E3106 Guide for Science-Based and Risk-Based Cleaning
medical devices (see Test Method G122 and Guide G127). It
Process Development and Validation
also is applicable to other systems where contamination is a
F303 Practices for Sampling for Particles in Aerospace
concern.
Fluids and Components
1.2 Several classes of contaminants/residues most likely to
F312 Test Methods for Microscopical Sizing and Counting
be found in oxygen equipment, pharmaceutical manufacturing
Particles from Aerospace Fluids on Membrane Filters
equipment, and medical devices are identified. However, if the
F324 Test Method for Nonvolatile Residue of Volatile
user of this practice has identified contaminants not included in
Cleaning Solvents Using the Solvent Purity Meter (With-
these classes, such identified contaminants may be substituted
drawn 1987)
for the preparation of the test coupons if appropriate for this
F331 Test Method for Nonvolatile Residue of Solvent Ex-
test method.
tract from Aerospace Components (Using Flash Evapora-
tor)
1.3 Solvent and cleaning agent compatibility with nonme-
F3127 GuideforValidatingCleaningProcessesUsedDuring
tallic substrates should be verified prior to the preparation of
the Manufacture of Medical Devices
the test coupons. Typical nonmetallic materials utilized in
G63 Guide for Evaluating Nonmetallic Materials for Oxy-
oxygen systems are contained in Guide G63.
gen Service
1.4 This practice may involve hazardous materials, G94 Guide for Evaluating Metals for Oxygen Service
operations, and equipment. This practice does not purport to G122 Test Method for Evaluating the Effectiveness of
Cleaning Agents
address all of the safety concerns associated with its use. It is
the responsibility of whomever uses this practice to consult and G127 Guide for the Selection of Cleaning Agents for
Oxygen-Enriched Systems
establish appropriate safety, health, and environmental prac-
tices and determine the applicability of regulatory limitations
2.2 ANSI Standard:
prior to use.
B46.1 Surface Texture (Surface Roughness, Waviness, and
1.5 This international standard was developed in accor-
Lay)
dance with internationally recognized principles on standard-
ization established in the Decision on Principles for the
3. Terminology
Development of International Standards, Guides and Recom-
3.1 Definitions:
mendations issued by the World Trade Organization Technical
Barriers to Trade (TBT) Committee.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
This practice is under the jurisdiction of ASTM Committee G04 on Compat- Standards volume information, refer to the standard’s Document Summary page on
ibility and Sensitivity of Materials in Oxygen Enriched Atmospheres and is the the ASTM website.
direct responsibility of Subcommittee G04.02 on Recommended Practices. The last approved version of this historical standard is referenced on
Current edition approved Dec. 1, 2018. Published January 2019. Originally www.astm.org.
ɛ1 4
approved in 1993. Last previous edition approved in 2015 as G121 – 98 (2015) . Available from American National Standards Institute (ANSI), 25 W. 43rd St.,
DOI: 10.1520/G0121-18. 4th Floor, New York, NY 10036, http://www.ansi.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
G121 − 18
3.1.1 blank, n—the contamination level of the fluid when by weighing the test coupons before and after application. The
the test coupon is omitted. amount of contaminant applied should be controlled and the
variation in weight between test coupons minimized. Test
3.1.1.1 Discussion—Sometimesreferredtoas“background”
coupons should be tested in a manner that simulates the actual
level.
cleaning conditions for the product, equipment, or system.
3.1.2 cleaning agent, n—an agent used to support the
Coupons may be tested immediately to simulate actual clean-
removal of contaminant from equipment surfaces or other
ing conditions or dried under specified conditions (for
critical objects (such as a medical device).
example,ambientovernight,8 hat104 °C,etc.)priortotesting
3.1.3 contaminant (contamination), n—unwanted
(for example, for Dirty Hold Time studies). Nonmetallic
molecular, non-volatile residue (NVR), and/or particulate mat-
material test coupons used as inserts, seats, seals, gaskets, etc.
ter that could adversely affect or degrade the operation, life, or
mayalsobepreparedbythisprocedureandareevaluatedunder
reliability of the systems or components upon which they
actual cleaning conditions.
reside.
4.2 Three methods of test coupon preparation are used:
3.1.3.1 Discussion—The contaminant could be a drug
Method A: NVR sample, single side,
substance, an intermediate, a formulated product, a lubricant, a
Method B: NVR sample, double side, and
machining oil, a solvent, a cleaning agent, etc. The contami-
Method C: NVR and particulate sample.
nant may migrate to other surfaces or users may become
exposed to the contaminant during the use of equipment.
5. Significance and Use
3.1.4 contaminate, v—a process of applying contaminant
5.1 This practice will be suitable to direct the preparation of
(non-volatile residue (NVR) and/or particulate matter).
test coupons with a known amount of contaminant on the
3.1.5 control coupon (witness coupon), n—a coupon made
surface. A standard test coupon is described and a list of
from the same material as the test coupons, but in this test
contaminants that have typically been found in oxygen-
method is not coated with the contaminant.
enriched systems and components is provided.
3.1.6 dirty hold time (DHT), n—the maximum time interval
5.2 These test coupons shall be used in the evaluation of
between equipment use and cleaning.
cleaning agents for oxygen-enriched systems and components.
3.1.7 molecular contaminant (non-particulate
This will permit direct comparison within and between test
contamination), n—molecular contaminants that may exist in a
facilities.
gaseous, liquid, or solid state and may be uniformly or
non-uniformly distributed.
5.3 Materials used in other fluid handling systems such as
3.1.7.1 Discussion—Molecular contaminants may be found
nitrogen,helium,hydrogen,gasoline,etc.mayalsobeprepared
as a solution, an emulsion, or in the form of droplets.
for evaluation by this practice.
Molecular contaminants account for most of what constitutes
NVR.
6. Apparatus
3.1.8 nonvolatile residue (NVR), n—a molecular and par-
6.1 Test Coupon—Panels of the same material of construc-
ticulatematterremainingfollowingthefiltrationandcontrolled
tion and finish as the equipment, product, or system to be
evaporation of a solvent containing contaminants.
cleaned. Other alloys that may be used if the specific alloy is
3.1.9 particle (particulate contaminant), n—a general term
unknown are included in Guide G94. Test coupons should be
used to describe a finely divided solid of organic or inorganic
numbered and in a manner that prevents removal during
matter with observable length, width, and thickness.
testing. A specified area of the test coupon may be designated
3.1.9.1 Discussion—Particulates are usually reported as the
as the test area where the test material is applied. Test coupons
amount of contaminant by the population of a specific microm-
may be of different test area dimensions (for example, 5 cm x
eter size, usually defined by its greatest dimension. See
5 cm, 10 cm x 10 cm) depending on the test procedure they are
methods described in Test Methods F312, Practices F303,or
used in.An example test coupon configuration is shown in Fig.
ARP 598 for particle size and population determination.
1.
3.1.10 surface roughness, R,n—the arithmetic average
a
NOTE1—Thesurfacefinishofthetestcouponshouldbethesameasthe
deviation of the surface profile from the centerline, normally
part to be cleaned.
reported in micrometres.
6.2 Balance—Range to a minimum of 50 g with an 0.1-mg
3.1.11 test coupon, n—representative surface that is typi-
accuracy capable of weighing to 60.1 mg.
cally a rectangular piece of a material of construction on which
6.3 Convection Oven—Capable of maintaining
a known amount of a compound is deposited to simulate a
50 °C 6 5 °C.
process residue.
6.4 Spray Applicator—Capable of applying an even coat of
4. Summary of Practice
contaminant; that is, an artist’s airbrush, perfume atomizer, or
4.1 The contaminant under study is applied to either one a spray device such as that used with window or tile cleaners
side or both sides of precleaned test coupons in a defined area. has been found to apply an even coating of the contaminant in
The amount of contaminant on the test coupons is determined a controlled manner.
G121 − 18
Intermediates of Active Pharmaceutical Ingredients,
Finished Pharmaceutical Products,
Biological products (proteins, fermentation broth, etc.),
Cosmetic products,
Degradants,
Excipients,
Etc.
7.2.1 Solvent-reagent-grade used to prepare standard solu-
tions of contaminants may include USP Purified Water and
Water for Injection, and solvents such as Methanol, Ethanol,
Isopropyl Alcohol, etc.
7.3 Desiccant—for example, silica gel.
7.4 Particulate Contaminant—fine (0- to 80-µm), or coarse
(0- to 200-µm) powders/particles.
8. Procedure
8.1 Test Coupon Preparation:
8.1.1 Test coupons should be prepared from the same
Material of Construction (MOC) and with the same material
grade (for example, SS 316L/#4) that will be used in the
equipment, product, or system under study. The test coupons
shall be numbered and precleaned prior to use and the number
recorded. If surface roughness is a variable in the application,
selecting the roughest surface finish for the test coupons is
FIG. 1 Example Test Coupon
advisable to represent worst-case conditions. The surface
roughness, R , of representative test coupons of each alloy can
a
be evaluated perANSI B46.1 and recorded.The surface area to
6.5 Other standard equipment such as a vacuum filtration
be contaminated (S) of each of the test coupons should be
system, solvent resistant filters, gloves, laboratory glassware,
predetermined (for example, 5 cm x 5 cm, 5 cm x 10 cm, etc.).
syringes, pipettes, desiccator, laboratory tongs, tweezers, and
The test coupons may also have an inscribed test area. If
wire.
desired, attach a handling wire through the hole at the top of
each of the test coupons. New test coupons should be cleaned
7. Reagents
prior to use with a similar procedure to that used for the
7.1 Contaminant Materials—General classes of materials
equipment MOC under study (for example, stainless steel test
that have typically been found in oxygen-enriched systems and
coupons should be passivated prior to use). Test coupons
components as a result of the manufacturing, assembly,
should be cleaned after use with a defined procedure that
fabrication, and construction processes include:
restores the test coupons’ surfaces to their original state (for
silicone oils and greases,
example, original starting weight or less). Prepare one control
fluorinated aerospace fluids and greases,
coupon with the test coupons to be contaminated for each
petroleum based oils,
cleaningagenttobeevaluatedifacontrolwillbeused.Thetest
ester based oils,
coupons shall be dried and stored until needed to av
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
´1
Designation: G121 − 98 (Reapproved 2015) G121 − 18
Standard Practice for
Preparation of Contaminated Test Coupons for the
Evaluation of Cleaning Agents
This standard is issued under the fixed designation G121; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
ε NOTE—Editorial changes were made throughout in October 2015.
1. Scope
1.1 This practice describes the procedure for the preparation of single- and double-sided contaminated metallic test coupons for
the evaluation of cleaning agents. It is applicable for the evaluation of cleaning agents proposed for the cleaning of
oxygen-enriched systems and components. oxygen equipment, pharmaceutical manufacturing equipment, and medical devices (see
Test Method G122 and Guide G127). It also is applicable to other systems where contamination is a concern.
1.2 Several classes of contaminantscontaminants/residues most likely to be found in oxygen-enriched systems and components
oxygen equipment, pharmaceutical manufacturing equipment, and medical devices are identified. However, if the user of this
practice has identified contaminants not included in these classes, such identified contaminants may be substituted for the
preparation of the test coupons.coupons if appropriate for this test method.
1.3 Preparation of nonmetallic substrates is not addressed, although similar methodology may be used. Solvent and cleaning
agent compatibility with the nonmetallic substratesubstrates should be verified prior to the preparation of the test coupons. Typical
nonmetallic materials utilized in oxygen systems are contained in Guide G63.
1.4 This practice may involve hazardous materials, operations, and equipment. This practice does not purport to address all
of the safety concerns associated with its use. It is the responsibility of whomever uses this practice to consult and establish
appropriate safety safety, health, and healthenvironmental practices and determine the applicability of regulatory limitations prior
to use.
1.5 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
2.1 ASTM Standards:
D1193 Specification for Reagent Water
E1235 Test Method for Gravimetric Determination of Nonvolatile Residue (NVR) in Environmentally Controlled Areas for
Spacecraft
E3106 Guide for Science-Based and Risk-Based Cleaning Process Development and Validation
F303 Practices for Sampling for Particles in Aerospace Fluids and Components
F312 Test Methods for Microscopical Sizing and Counting Particles from Aerospace Fluids on Membrane Filters
F324 Test Method for Nonvolatile Residue of Volatile Cleaning Solvents Using the Solvent Purity Meter (Withdrawn 1987)
F331 Test Method for Nonvolatile Residue of Solvent Extract from Aerospace Components (Using Flash Evaporator)
F3127 Guide for Validating Cleaning Processes Used During the Manufacture of Medical Devices
G63 Guide for Evaluating Nonmetallic Materials for Oxygen Service
G94 Guide for Evaluating Metals for Oxygen Service
G122 Test Method for Evaluating the Effectiveness of Cleaning Agents
This practice is under the jurisdiction of ASTM Committee G04 on Compatibility and Sensitivity of Materials in Oxygen Enriched Atmospheres and is the direct
responsibility of Subcommittee G04.02 on Recommended Practices.
Current edition approved Sept. 1, 2004Dec. 1, 2018. Published October 2015January 2019. Originally approved in 1993. Last previous edition approved in 20102015 as
ɛ1
G121 – 98 (2010)(2015) . DOI: 10.1520/G0121-98R15E01.10.1520/G0121-18.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
The last approved version of this historical standard is referenced on www.astm.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
G121 − 18
G127 Guide for the Selection of Cleaning Agents for Oxygen-Enriched Systems
2.2 ANSI:ANSI Standard:
B 46.1B46.1 Surface Texture (Surface Roughness, Waviness, and Lay)
3. Terminology
3.1 Definitions:
3.1.1 blank, n—the contamination level of the fluid when the test coupon is omitted.
3.1.1.1 Discussion—
Sometimes referred to as “background” level.
3.1.2 cleaning agent, n—an agent used to support the removal of contaminant from equipment surfaces or other critical objects
(such as a medical device).
3.1.3 contaminant, contaminant (contamination), n—unwanted molecular and molecular, non-volatile residue (NVR), and/or
particulate matter that could adversely affect or degrade the performance operation, life, or reliability of the systems or components
upon which they reside.
3.1.3.1 Discussion—
The contaminant could be a drug substance, an intermediate, a formulated product, a lubricant, a machining oil, a solvent, a
cleaning agent, etc. The contaminant may migrate to other surfaces or users may become exposed to the contaminant during the
use of equipment.
3.1.4 contamination,contaminate, n—v—a process of contaminating.applying contaminant (non-volatile residue (NVR) and/or
particulate matter).
3.1.3 surface roughness, R , n—the arithmetic average deviation of the surface profile from the centerline, normally reported
a
in micrometres.
3.1.4 nonvolatile residue (NVR), n—residual molecular and particulate matter remaining following the filtration of a solvent
containing contaminants and evaporation of the solvent at a specified temperature.
3.1.5 particle (particulate contaminant), control coupon (witness coupon), n—a piece of matter in a solid state with observable
length, width, and thickness.coupon made from the same material as the test coupons, but in this test method is not coated with
the contaminant.
3.1.5.1 Discussion—
The size of a particle is usually defined by its great dimension and is specified in micrometres.
3.1.6 dirty hold time (DHT), n—the maximum time interval between equipment use and cleaning.
3.1.7 molecular contaminant (nonparticulate(non-particulate contamination), n—the molecular contaminant contaminants that
may beexist in a gaseous, liquid, or solid state.state and may be uniformly or non-uniformly distributed.
3.1.7.1 Discussion—
It may be uniformly or nonuniformly distributed, or be Molecular contaminants may be found as a solution, an emulsion, or in
the form of droplets. Molecular contaminants account for most of the what constitutes NVR.
3.1.8 blank, nonvolatile residue (NVR), n—the contamination level of the fluid when the test coupon is omitted.a molecular and
particulate matter remaining following the filtration and controlled evaporation of a solvent containing contaminants.
3.1.7.1 Discussion—
Sometimes referred to as “background” level.
3.1.9 control coupon (witness coupon), particle (particulate contaminant), n—a coupon made from the same material as the test
coupons, but in this test method is not coated with the contaminant.general term used to describe a finely divided solid of organic
or inorganic matter with observable length, width, and thickness.
Dusts of varying particle sizes are available from the AC Spark Plug Division of General Motors, 1300-T N. Dort Hwy., Flint, MI 48556.Available from American
National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http://www.ansi.org.
G121 − 18
3.1.9.1 Discussion—
Particulates are usually reported as the amount of contaminant by the population of a specific micrometer size, usually defined by
its greatest dimension. See methods described in Test Methods F312, Practices F303, or ARP 598 for particle size and population
determination.
3.1.10 surface roughness, R , n—the arithmetic average deviation of the surface profile from the centerline, normally reported
a
in micrometres.
3.1.11 test coupon, n—representative surface that is typically a rectangular piece of a material of construction on which a known
amount of a compound is deposited to simulate a process residue.
4. Summary of Practice
4.1 A solution of the contaminant The contaminant under study is applied to either one side or both sides of the precleaned test
coupons and dried under standard conditions. in a defined area. The amount of contaminant on the test coupons is determined.
determined by weighing the test coupons before and after application. The amount of contaminant applied should be controlled
and the variation in weight between test coupons minimized. Test coupons should be tested in a manner that simulates the actual
cleaning conditions for the product, equipment, or system. Coupons may be tested immediately to simulate actual cleaning
conditions or dried under specified conditions (for example, ambient overnight, 8 h at 104 °C, etc.) prior to testing (for example,
for Dirty Hold Time studies). Nonmetallic material test coupons used as inserts, seats, seals, gaskets, etc. may also be prepared
by this procedure and are evaluated in the as-used condition.under actual cleaning conditions.
4.2 Three methods of test coupon preparation are used:
Method A,A: NVR sample, single side,
Method B,B: NVR sample, double side side, and
Method C,C: NVR and particulate samplesample.
5. Significance and Use
5.1 This practice will be suitable to direct the preparation of test coupons with a known amount of contaminant on the surface.
A standard test coupon is described and a list of contaminants that have typically been found in oxygen-enriched systems and
components is provided.
5.2 These test coupons shall be used in the evaluation of cleaning agents for oxygen-enriched systems and components. This
will permit direct comparison within and between test facilities.
5.3 Materials used in other fluid handling systems such as nitrogen, helium, hydrogen, gasoline, etc. may also be prepared for
evaluation by this practice.
6. Apparatus
6.1 Test Coupon—Metal panels Panels of the same material as the component part of construction and finish as the equipment,
product, or system to be cleaned. Other alloys that may be used if the specific alloy is unknown are included in Guide G94. The
coupon Test coupons should be numbered and in a manner that prevents removal during testing. A specified area of the test coupon
may be designated as the test area where the test material is applied. Test coupons may be of different test area dimensions (for
example, 5 cm x 5 cm, 10 cm x 10 cm) depending on the test procedure they are used in. An example test coupon configuration
is shown in Fig. 1.
NOTE 1—The surface finish of the test coupon should be the same as the part to be cleaned.
6.2 Balance-Range Balance—Range to a minimum of 50 g with an 0.1-mg accuracy capable of weighing to 60.1 mg.
6.3 Oven-Convection, Convection Oven—capableCapable of maintaining 50°C 6 5°C.50 °C 6 5 °C.
6.4 Spray Applicator—Capable of applying an even coat of contaminant; that is, an artist’s airbrush, perfume atomizer, or a
spray device such as that used with window or tile cleaners has been found to apply an even coating of the contaminant in a
controlled manner.
6.5 Other standard equipment such as a vacuum filtration system, solvent resistant filters, gloves, laboratory glassware, syringes,
pipettes, desiccator, laboratory tongs, tweezers, and wire.
7. Reagents
7.1 Contaminant Materials—Contaminant materials-general General classes of materials that have typically been found in
oxygen-enriched systems and components as a result of the manufacturing, assembly, fabrication, and construction processes
include:
silicone oils and greases,
fluorinated aerospace fluids and greases,
G121 − 18
FIG. 1 StandardExample Test Coupon
petroleum based oils and greases,oils,
ester based oils and greases,oils,
phosphate esters,
waxes,
chlorotrifluoroethylene based oils and greases,oils,
inks,
cutting oils, and
dye penetrants.
7.1.1 Solvent-reagent-grade used to prepare standard solutions of contaminants which may include the following: 2-propanol,
2-butanone, hexane, Type II reagent water, or better, in accordance with Specification D1193, and perfluorinated carbon fluids.
(Warning—Solvents such as 2-propanol hexane and 2-butanone are highly flammable. Appropriate safe handling procedures
should be used.)
7.2 Contaminant materials—Solvent-reagent-grade used to prepare standard solutions of contaminants which may include the
following: 2-propanol, 2-butanone, hexane, Type II reagent water, or better, in accordance with SpecificationClasses of materials
that are typically evaluated in health care industry products, equipment, and processes include but are not limited to D1193, and
perfluorinated carbon fluids. (the following:Warning—Solvents such as 2-propanol hexane and 2-butanone are highly flammable.
The reader should refer to appropriate safe handling procedures.)
Active Pharmaceutical Ingredients,
Intermediates of Active Pharmaceutical Ingredients,
Finished Pharmaceutical Products,
Biological products (proteins, fermentation broth, etc.),
Cosmetic products,
Degradants,
Excipients,
Etc.
7.2.1 Solvent-reagent-grade used to prepare standard solutions of contaminants may include USP Purified Water and Water for
Injection, and solvents such as Methanol, Ethanol, Isopropyl Alcohol, etc.
...