ASTM G224-23
(Practice)Standard Practice for Operating UVC Lamp Apparatus for Exposure of Materials
Standard Practice for Operating UVC Lamp Apparatus for Exposure of Materials
SIGNIFICANCE AND USE
5.1 Material resistance to photodegradation caused by exposure to artificial UVC light sources is a growing concern due to the use of ultraviolet germicidal irradiation (UVGI) to mitigate the spread of infectious diseases.
5.2 Materials and products intended for direct sunlight exposure are typically designed to resist the effects of the UVA and UVB light reaching the earth’s surface, but generally they are not tested to determine the effects of exposure to UVC, which is filtered out by the atmosphere.
5.3 Compared to light in the UVA and UVB regions of the electromagnetic spectrum, UVC light, when absorbed by a material, can cause photodegradation to proceed at different rates and by different mechanisms as well as confining degradation to a thinner surface layer.
5.4 Indoor materials and products, which typically are not designed to withstand significant ultraviolet light exposure, are at even greater risk of premature degradation when subjected to UVC exposure.
5.5 This practice is intended to induce property changes consistent with those experienced by materials exposed to artificial UVC light sources with a similar spectral irradiance distribution to those specified in this practice.
SCOPE
1.1 This practice is limited to the basic principles for operating a low-pressure mercury lamp apparatus to assess degradation of materials due to exposure to UVC light; on its own, it does not deliver a specific result.
1.2 It is intended to be used in conjunction with a practice or method that defines specific exposure conditions for an application along with a means to evaluate changes in material properties. This practice is intended to reproduce the photodegradation effects that occur when materials are exposed to artificial light sources that emit radiation primarily in the UVC wavelength band, particularly in the range of 240 nm to 280 nm. This practice is limited to the procedures for obtaining, measuring, and controlling conditions of exposure.
Note 1: Practice G151 describes general procedures to be used when exposing materials in accelerated test devices that use laboratory light sources.
Note 2: A common use of UVC light sources is for the disinfection of surfaces and air, a process known as ultraviolet germicidal irradiation (UVGI). Water disinfection applications using UVC light sources have been in use for many decades.
1.3 This practice does not cover other light sources (e.g. LEDs, excimer lamps, etc.) or any lamps that emit wavelengths primarily outside the range in 1.2.
1.4 Specimens are exposed to UVC light controlled to a specified irradiance level under controlled temperature conditions.
1.5 Specimen preparation and evaluation of the results are covered in ASTM methods or specifications for specific materials. General guidance is given in Practice G151.
1.6 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.
1.8 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
- 31-Jan-2023
- Technical Committee
- G03 - Weathering and Durability
- Drafting Committee
- G03.03 - Simulated and Controlled Exposure Tests
Relations
- Effective Date
- 01-Jun-2020
- Effective Date
- 01-Mar-2014
- Effective Date
- 01-Dec-2012
- Effective Date
- 01-Jun-2012
- Effective Date
- 01-Apr-2010
- Effective Date
- 01-Jul-2009
- Effective Date
- 15-Jun-2009
- Effective Date
- 01-Aug-2008
- Effective Date
- 01-Dec-2006
- Effective Date
- 01-Dec-2006
- Effective Date
- 15-Nov-2006
- Effective Date
- 05-Jun-2006
- Effective Date
- 01-Jun-2006
- Effective Date
- 15-Aug-2005
- Effective Date
- 01-Oct-2004
Overview
ASTM G224-23: Standard Practice for Operating UVC Lamp Apparatus for Exposure of Materials establishes protocols for exposing materials to UVC light using low-pressure mercury lamp apparatus. As the use of ultraviolet germicidal irradiation (UVGI) expands for disinfecting surfaces and air, the need to understand the effects of artificial UVC exposure on materials has increased. This practice defines the basic operating principles for such exposures but does not specify particular test results or material evaluations. Instead, ASTM G224-23 provides a framework to reliably assess the photodegradation of materials due to UVC irradiation, particularly for wavelengths between 240 nm and 280 nm.
Key Topics
- Material Degradation under UVC: Most products are designed to withstand UVA and UVB radiation found in natural sunlight, but are rarely tested for UVC exposure-a type of ultraviolet light filtered by the earth’s atmosphere but now prevalent in artificial disinfection systems.
- UVC Exposure Conditions: The standard describes the operation of UVC lamp apparatus, including control of irradiance (especially at 254 nm), temperature, and specimen positioning to simulate realistic exposure scenarios.
- Specimen Handling: Guidance is provided for specimen preparation, mounting, and repositioning to ensure uniform exposure and reliable test results.
- Safety and Calibration: The practice highlights the importance of safety precautions for UVC exposure and requires periodic calibration of irradiance and temperature control instruments using traceable standards.
Applications
ASTM G224-23 is essential for manufacturers, testing laboratories, and product developers assessing how materials will perform under artificial UVC light exposure, particularly in environments where disinfection using UVGI is routine. Key applications include:
- Assessment of Indoor Materials: Indoor products, generally not designed for UV resistance, can be vulnerable when exposed to UVC light from germicidal lamps. This standard helps simulate and evaluate such risks.
- Evaluation of Protective Equipment and Coatings: Personal protective equipment (PPE), medical devices, coatings, and plastics subject to UVC-based sterilization can undergo changes in durability and performance that must be understood prior to deployment.
- Product Development for UV Disinfection Environments: Manufacturers can use ASTM G224-23 to improve material formulations and product designs to withstand repeated UVC exposure in healthcare, transport, or public settings.
- Comparative Testing: The practice can be paired with other ASTM or ISO methods to systematically compare and improve materials’ UVC resistance.
Related Standards
ASTM G224-23 is closely connected to several other standards focused on weathering, UV exposure, and equipment calibration:
- ASTM G151 – General procedures for exposing nonmetallic materials in accelerated test devices using laboratory light sources.
- ASTM G130 – Calibration method for ultraviolet radiometers.
- ASTM G154 – Operating fluorescent ultraviolet (UV) lamp apparatus for material exposure.
- IEC 60335-1 – General safety requirements for household and similar electrical appliances, including UV lamp devices.
- CIE Technical Report 187 – Health and safety guidance regarding UVC exposure.
Practical Value
By following ASTM G224-23, organizations can systematically evaluate the effects of UVC light on a wide range of materials and products, ensuring safety, compliance, and product durability in settings where UVGI is an integral part of disinfection protocols. The standard helps to:
- Reduce the risk of unexpected material failures due to UVC-induced degradation.
- Guide product improvements for increased longevity in UVC-disinfected environments.
- Facilitate regulatory compliance and product claims related to UVC resistance.
Keywords: UVC exposure, ultraviolet germicidal irradiation (UVGI), material durability, low-pressure mercury lamp, photodegradation, accelerated weathering, ASTM G224-23, UVC testing, disinfection, indoor material performance
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Frequently Asked Questions
ASTM G224-23 is a standard published by ASTM International. Its full title is "Standard Practice for Operating UVC Lamp Apparatus for Exposure of Materials". This standard covers: SIGNIFICANCE AND USE 5.1 Material resistance to photodegradation caused by exposure to artificial UVC light sources is a growing concern due to the use of ultraviolet germicidal irradiation (UVGI) to mitigate the spread of infectious diseases. 5.2 Materials and products intended for direct sunlight exposure are typically designed to resist the effects of the UVA and UVB light reaching the earth’s surface, but generally they are not tested to determine the effects of exposure to UVC, which is filtered out by the atmosphere. 5.3 Compared to light in the UVA and UVB regions of the electromagnetic spectrum, UVC light, when absorbed by a material, can cause photodegradation to proceed at different rates and by different mechanisms as well as confining degradation to a thinner surface layer. 5.4 Indoor materials and products, which typically are not designed to withstand significant ultraviolet light exposure, are at even greater risk of premature degradation when subjected to UVC exposure. 5.5 This practice is intended to induce property changes consistent with those experienced by materials exposed to artificial UVC light sources with a similar spectral irradiance distribution to those specified in this practice. SCOPE 1.1 This practice is limited to the basic principles for operating a low-pressure mercury lamp apparatus to assess degradation of materials due to exposure to UVC light; on its own, it does not deliver a specific result. 1.2 It is intended to be used in conjunction with a practice or method that defines specific exposure conditions for an application along with a means to evaluate changes in material properties. This practice is intended to reproduce the photodegradation effects that occur when materials are exposed to artificial light sources that emit radiation primarily in the UVC wavelength band, particularly in the range of 240 nm to 280 nm. This practice is limited to the procedures for obtaining, measuring, and controlling conditions of exposure. Note 1: Practice G151 describes general procedures to be used when exposing materials in accelerated test devices that use laboratory light sources. Note 2: A common use of UVC light sources is for the disinfection of surfaces and air, a process known as ultraviolet germicidal irradiation (UVGI). Water disinfection applications using UVC light sources have been in use for many decades. 1.3 This practice does not cover other light sources (e.g. LEDs, excimer lamps, etc.) or any lamps that emit wavelengths primarily outside the range in 1.2. 1.4 Specimens are exposed to UVC light controlled to a specified irradiance level under controlled temperature conditions. 1.5 Specimen preparation and evaluation of the results are covered in ASTM methods or specifications for specific materials. General guidance is given in Practice G151. 1.6 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.8 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.
SIGNIFICANCE AND USE 5.1 Material resistance to photodegradation caused by exposure to artificial UVC light sources is a growing concern due to the use of ultraviolet germicidal irradiation (UVGI) to mitigate the spread of infectious diseases. 5.2 Materials and products intended for direct sunlight exposure are typically designed to resist the effects of the UVA and UVB light reaching the earth’s surface, but generally they are not tested to determine the effects of exposure to UVC, which is filtered out by the atmosphere. 5.3 Compared to light in the UVA and UVB regions of the electromagnetic spectrum, UVC light, when absorbed by a material, can cause photodegradation to proceed at different rates and by different mechanisms as well as confining degradation to a thinner surface layer. 5.4 Indoor materials and products, which typically are not designed to withstand significant ultraviolet light exposure, are at even greater risk of premature degradation when subjected to UVC exposure. 5.5 This practice is intended to induce property changes consistent with those experienced by materials exposed to artificial UVC light sources with a similar spectral irradiance distribution to those specified in this practice. SCOPE 1.1 This practice is limited to the basic principles for operating a low-pressure mercury lamp apparatus to assess degradation of materials due to exposure to UVC light; on its own, it does not deliver a specific result. 1.2 It is intended to be used in conjunction with a practice or method that defines specific exposure conditions for an application along with a means to evaluate changes in material properties. This practice is intended to reproduce the photodegradation effects that occur when materials are exposed to artificial light sources that emit radiation primarily in the UVC wavelength band, particularly in the range of 240 nm to 280 nm. This practice is limited to the procedures for obtaining, measuring, and controlling conditions of exposure. Note 1: Practice G151 describes general procedures to be used when exposing materials in accelerated test devices that use laboratory light sources. Note 2: A common use of UVC light sources is for the disinfection of surfaces and air, a process known as ultraviolet germicidal irradiation (UVGI). Water disinfection applications using UVC light sources have been in use for many decades. 1.3 This practice does not cover other light sources (e.g. LEDs, excimer lamps, etc.) or any lamps that emit wavelengths primarily outside the range in 1.2. 1.4 Specimens are exposed to UVC light controlled to a specified irradiance level under controlled temperature conditions. 1.5 Specimen preparation and evaluation of the results are covered in ASTM methods or specifications for specific materials. General guidance is given in Practice G151. 1.6 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.8 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.
ASTM G224-23 is classified under the following ICS (International Classification for Standards) categories: 29.140.30 - Fluorescent lamps. Discharge lamps. The ICS classification helps identify the subject area and facilitates finding related standards.
ASTM G224-23 has the following relationships with other standards: It is inter standard links to ASTM G130-12(2020), ASTM G113-14, ASTM G154-12, ASTM G130-12, ASTM G151-10, ASTM G151-09, ASTM G113-09, ASTM G113-08, ASTM G113-06e1, ASTM G113-06, ASTM G151-06, ASTM G154-06, ASTM G130-06, ASTM G113-05, ASTM G154-04. Understanding these relationships helps ensure you are using the most current and applicable version of the standard.
ASTM G224-23 is available in PDF format for immediate download after purchase. The document can be added to your cart and obtained through the secure checkout process. Digital delivery ensures instant access to the complete standard document.
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: G224 − 23
Standard Practice for
Operating UVC Lamp Apparatus for Exposure of Materials
This standard is issued under the fixed designation G224; 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 priate safety, health, and environmental practices and deter-
mine the applicability of regulatory limitations prior to use.
1.1 This practice is limited to the basic principles for
1.8 This international standard was developed in accor-
operating a low-pressure mercury lamp apparatus to assess
dance with internationally recognized principles on standard-
degradation of materials due to exposure to UVC light; on its
ization established in the Decision on Principles for the
own, it does not deliver a specific result.
Development of International Standards, Guides and Recom-
1.2 It is intended to be used in conjunction with a practice or
mendations issued by the World Trade Organization Technical
method that defines specific exposure conditions for an appli-
Barriers to Trade (TBT) Committee.
cation along with a means to evaluate changes in material
properties. This practice is intended to reproduce the photo- 2. Referenced Documents
degradation effects that occur when materials are exposed to
2.1 ASTM Standards:
artificial light sources that emit radiation primarily in the UVC
G113 Terminology Relating to Natural and Artificial Weath-
wavelength band, particularly in the range of 240 nm to
ering Tests of Nonmetallic Materials
280 nm. This practice is limited to the procedures for
G130 Test Method for Calibration of Narrow- and Broad-
obtaining, measuring, and controlling conditions of exposure.
Band Ultraviolet Radiometers Using a Spectroradiometer
G151 Practice for Exposing Nonmetallic Materials in Accel-
NOTE 1—Practice G151 describes general procedures to be used when
exposing materials in accelerated test devices that use laboratory light erated Test Devices that Use Laboratory Light Sources
sources.
G154 Practice for Operating Fluorescent Ultraviolet (UV)
NOTE 2—A common use of UVC light sources is for the disinfection of
Lamp Apparatus for Exposure of Materials
surfaces and air, a process known as ultraviolet germicidal irradiation
2.2 IEC Standards:
(UVGI). Water disinfection applications using UVC light sources have
IEC 60335-1 Household and similar electrical appliances -
been in use for many decades.
Safety - Part 1: General requirements
1.3 This practice does not cover other light sources (e.g.
LEDs, excimer lamps, etc.) or any lamps that emit wavelengths
3. Terminology
primarily outside the range in 1.2.
3.1 Definitions:
1.4 Specimens are exposed to UVC light controlled to a
3.1.1 The definitions given in Terminology G113 are appli-
specified irradiance level under controlled temperature condi-
cable to this practice.
tions.
3.2 Definitions of Terms Specific to This Standard:
3.2.1 As used in this practice, the term sunlight is identical
1.5 Specimen preparation and evaluation of the results are
to the terms daylight and solar irradiance, global as they are
covered in ASTM methods or specifications for specific
defined in Terminology G113.
materials. General guidance is given in Practice G151.
3.2.2 UVC, n—portion of the electromagnetic spectrum
1.6 Units—The values stated in SI units are to be regarded
comprising wavelengths between 100 nm and 280 nm, also
as standard. No other units of measurement are included in this
spelled UV-C.
standard.
1.7 This standard does not purport to address all of the 4. Summary of Practice
safety concerns, if any, associated with its use. It is the
4.1 Specimens are exposed to a UVC light source under
responsibility of the user of this standard to establish appro-
controlled conditions of irradiance and temperature.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
This practice is under the jurisdiction of ASTM Committee G03 on Weathering contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
and Durability and is the direct responsibility of Subcommittee G03.03 on Standards volume information, refer to the standard’s Document Summary page on
Simulated and Controlled Exposure Tests. the ASTM website.
Current edition approved Feb. 1, 2023. Published March 2023. DOI: 10.1520/ Available from American National Standards Institute (ANSI), 25 W. 43rd St.,
G0224-23. 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
G224 − 23
NOTE 3—The effects of water in liquid or vapor form are not
6. Apparatus
considered. It is expected that the relative humidity at the specimen
6.1 Apparatus that comply with the requirements of Practice
surface will be less than 50 % and could be less than 10 % depending on
G154 meet the requirements of this standard provided they
test and laboratory conditions.
meet the additional requirements in this section.
4.2 The exposure condition may be varied by selection of:
4.2.1 The lamp’s irradiance level, 6.2 Laboratory Light Source—The light source shall be one
4.2.2 The use of alternating conditions of darkness and
or more low-pressure mercury lamps, made with glass that
UVC exposure and the timing of each, and blocks all emissions at wavelengths below 200 nm to prevent
4.2.3 The temperature during each exposure condition.
the generation of ozone.
NOTE 4—Low-pressure mercury lamps emit ultraviolet light primarily
5. Significance and Use
in two spectral lines: 254 nm and 185 nm (1) . The 185 nm line is capable
of generating ozone when exposed to air, but certain glass types are able
5.1 Material resistance to photodegradation caused by ex-
to absorb it and prevent ozone production. These lamps emit additional
posure to artificial UVC light sources is a growing concern due
spectral lines in the visible range, giving them a blue-violet appearance.
to the use of ultraviolet germicidal irradiation (UVGI) to
The visible spectral lines are not considered in this document.
mitigate the spread of infectious diseases.
NOTE 5—Low-pressure mercury lamps are similar in construction to
typical UV fluorescent lamps, except they lack the white phosphor coating
5.2 Materials and products intended for direct sunlight
that creates the fluorescence effect.
exposure are typically designed to resist the effects of the UVA
6.2.1 Low-pressure mercury lamps are differentiated from
and UVB light reaching the earth’s surface, but generally they
other mercury lamps by their significantly lower gas fill
are not tested to determine the effects of exposure to UVC,
pressure. Other types of mercury lamps, such as medium or
which is filtered out by the atmosphere.
high pressure lamps, shall not be used.
5.3 Compared to light in the UVA and UVB regions of the
NOTE 6—For example, medium-pressure mercury lamps have fill
electromagnetic spectrum, UVC light, when absorbed by a
pressures of approximately 1 bar or higher, which significantly changes
material, can cause photodegradation to proceed at different
their spectral irradiance. In contrast, low-pressure mercury lamps typically
rates and by different mechanisms as well as confining degra-
have fill pressures less than 10 mbar.
dation to a thinner surface layer.
6.2.2 Lamps meeting these requirements are referred to as
5.4 Indoor materials and products, which typically are not
UVC-254 lamps. A spectral irradiance distribution, bandpass
designed to withstand significant ultraviolet light exposure, are
corrected, is shown in Fig. 1. See Appendix X1 for information
at even greater risk of premature degradation when subjected to
on measuring the spectral irradiance of low-pressure mercury
UVC exposure.
lamps.
5.5 This practice is intended to induce property changes
consistent with those experienced by materials exposed to
artificial UVC light sources with a similar spectral irradiance 4
The boldface numbers in parentheses refer to a list of references at the end of
distribution to those specified in this practice. this standard.
FIG. 1 Spectral Irradiance of UVA-254 Lamps, shown with irradiance of 6.0 mW ⁄(cm ·nm) at 254 nm, and reference sunlight spectrum,
G177
G224 − 23
6.3 Test chamber—The design of the test chamber may vary, frequently in accordance with manufacturer’s instructions.
but it shall be equipped to prevent UVC irradiance exposure of Calibration should be traceable to a national metrological
the test operator. Additionally, it shall provide means to control institute (NMI).
the test temperature.
NOTE 10—Typically, these devices are controlled by black-panel
thermometer, and not by chamber air temperature. Uninsulated black-
NOTE 7—See CIE Technical Report 187 for information on health and
panel thermometers are recommended for use with highly thermally-
safety concerns related to exposure to UVC lamps (2).
conductive or very thin specimens. Insulated black-panel thermometers
6.4 Irradiance Control—Irradiance shall be measured and
are recommended for use with insulating or thick specimens. Different
types of black-panel thermometers may result in significantly different
adjusted to maintain the specified level. Unless agreed upon
temperature profiles in the test chamber.
between interested parties, the apparatus shall be equipped
with an on-board irradiance sensor coupled with an electronic
7. Test Specimen
feedback loop to monitor and control the amount of radiant
energy at a wavelength of 254 nm received at the specimen 7.1 Refer to Practice G151 for guidance on test specimen
plane. The irradiance sensor shall comply with the require-
form and preparation, number of test specimens, and specimen
ments in Practice G151. storage and conditioning.
NOTE 8—In small devices, it may not be practical to have a sensor
8. Procedure
continuously monitoring the irradiance because the area of the sensor can
represent a significant proportion of the exposure area. In such cases, a
8.1 Prior to exposure, determine which specimen property
common technique for ensuring specified irradiance levels are maintained
or properties will be evaluated. Measure these properties in
is to measure and adjust the irradiance in the specimen area before the
accordance with recognized ASTM or other international
exposure, repeat as necessary at specified intervals during the exposure,
standards. If required for destructive tests or other reasons, use
and measure again at the end of the exposure.
unexposed file specimens to quantify the property.
6.5 Thermometer—Either an insulated or uninsulated black-
8.2 Ensure that the chamber, especially its irradiance mea-
panel thermometer shall be used to control test conditions.
These may be constructed from either aluminum or steel, and surement system, has been calibrated according to manufac-
turer guidelines.
they shall comply with the requirements in Practice G151.
6.5.1 The thermometer shall be mounted in the specimen
8.3 Specimen Mounting—Mount the specimens in holders
plane such that it is in the same relative position and orientation
so that the surface of interest faces the lamps. Mount speci-
to the lamps and receives the same conditions as the test
mens in such a way that applied stresses are minimized, unless
specimens.
such stresses are part of the test design.
6.5.2 The apparatus may provide chamber air temperature
8.4 Program the chamber to run the selected test conditions
control. Positioning and calibration of chamber air sensors
continuously throughout the required number of hours or
shall be in accordance with Practice G151.
cycles. See Section 9 for guidance on choosing test conditions
6.5.3 Test apparatus may be equipped with means to control
and duration. Interruptions to the test for maintenance or to
relative humidity and/or spray water onto specimens, but these
inspect specimens shall be minimized.
functions are not commonly used in typical UVC exposures.
8.5 Specimen Repositioning—Periodic specimen reposition-
6.6 Specimen Holders—Specimen holders shall be made of
ing is recommended to compensate for variations of irradiance
materials that are not susceptible to degradation caused by
and temperature within the specimen area. Repositioning is
UVC irradiation. The holders shall be equipped with panels or
required if specimens are placed in positions where the
other means to fill unused specimen areas during a test.
irradiance is less than 90 % of the value mea
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