ASTM G156-97 - 10.2.2002
 
1. Scope

1.1 This standard describes the criterion to be used for selection of a WRM and procedures to be used for determining within lab and between lab tolerances of changes in measured properties of a reference material intended for use in monitoring operating conditions to establish the consistency of exposure tests.

Note 1—Examples of laboratory accelerated tests in which a weathering reference material could be used to monitor consistency are light and water exposure tests such as those described in Practices G 152, G 153, and G 154 G 155and other standards in which tests conducted according to these standards are referenced. Examples of outdoor exposures where a weathering reference material could be used to monitor consistency are those conducted according to Practices G 7, G 24, or G 90. A reference material can also be used to monitor consistency of exposure or conditioning test that do not involve exposure to light.

1.2 This practice does not cover (1) control materials used for comparison of stability with test materials, or (2) standard materials used to time exposures.

1.3 This practice provides an outline of experiments required to determine how the measured properties of the reference material change as a function of exposure to specified test conditions. It includes establishment of reproducible measurement procedures, determination of the critical region in the light source causing the changes, and effects of other critical exposure stresses such as temperature and moisture.

1.4 This practice describes procedures for conducting round-robin tests with the weathering reference material to determine reproducibility of the reference material property change in exposures conducted in different laboratories, and the repeatability when replicate reference material specimens are exposed in a single device and tested in one laboratory.

1.5 This practice describes procedures for using the results from analysis of variance on results from round-robin tests to determine the contribution of the exposure, the measurement device, reference material variability, and operator error to total variability.

 
2. Referenced Documents

G152-13(2021)

Standard Practice for Operating Open Flame Carbon Arc Light Apparatus for Exposure of Nonmetallic Materials

G113-22

Standard Terminology Relating to Natural and Artificial Weathering Tests of Nonmetallic Materials

G90-23

Standard Practice for Performing Accelerated Outdoor Weathering of Materials Using Concentrated Natural Sunlight

G24-21

Standard Practice for Conducting Exposures to Daylight Filtered Through Glass

G7-05

Standard Practice for Atmospheric Environmental Exposure Testing of Nonmetallic Materials

E1169-21

Standard Practice for Conducting Ruggedness Tests

E177-20

Standard Practice for Use of the Terms Precision and Bias in ASTM Test Methods

SAE J1885,

Accelerated Exposure of Automotive Interior Materials Using a Controlled Irradiance Water-Cooled Xenon Arc Apparatus

G178-16(2023)

Standard Practice for Determining the Activation Spectrum of a Material (Wavelength Sensitivity to an Exposure Source) Using the Sharp Cut-On Filter or Spectrographic Technique

G155-21

Standard Practice for Operating Xenon Arc Lamp Apparatus for Exposure of Materials

G154-23

Standard Practice for Operating Fluorescent Ultraviolet (UV) Lamp Apparatus for Exposure of Materials

G153-13(2021)

Standard Practice for Operating Enclosed Carbon Arc Light Apparatus for Exposure of Nonmetallic Materials

E691-23

Standard Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method