AATCC 109-2016 Colorfastness to Ozone in the Atmosphere under Low Humidities.
8. Procedure
8.1 Suspend the test specimens in the exposure chamber (see 12.3). The test apparatus should be located in a room in which the ambient air temperature is 18 28°C (64-82°F) and the relative humidity does not exceed 67%. For reference and interlab testing, conduct tests in a room or chamber with the standard atmospheric conditions of 21 ± 2°C (70 ± 4°F) and 65 ± 5% RH. Ozone should be present in concentrations of 4.5 ± 1 ppm for 4.5 ± 1 h. This constitutes one cycle (see 12.5).
8.2 Remove those specimens which exhibit a color change at the end of one cycle. One cycle will generally produce a measurable color change in specimens which are ozone sensitive. 8.3 Run additional similar cycles as necessary.
9. Evaluation
9.1 At the end of each cycle immediately compare those specimens which are removed from the exposure chamber with the preserved originals from which they were drawn.
9.2 Rate the effect on color of test specimens after any specified number of cycles by reference to the Gray Scale for Color Change [AATCC Evaluation Procedure (EP) 1] or using EP7, Instrumental Assessment of the Change in Color of a Test Specimen, and record the numerical rating that corresponds to the appropriate one on the Gray Scale. Report the number of cycles run (see 12.6).
10. Report
10.1 Report the numerical grade for the change in color of each test specimen, the number of cycles run and the temperature and relative humidity at which the test was performed. 11. Precision and Bias
11.1 Precision. Precision for this test method has not been established. Until a precision statement is generated for this test method, use standard statistical techniques in making any comparisons of test results for either within-laboratory or betweenaboratory averages.
11.2 Bias. Colorfastness to ozone in the atmosphere under low humidities can be defined only in terms of a test method. There is no independent method for determining the true values. As a means of estimating these properties, the method has no known bias.AATCC 109 pdf download.