ASTM D 3273 : 2021

1.1This test method describes the use of an environmental chamber and operating conditions to evaluate the relative resistance of interior coatings to surface fungal growth in a severe interior environment during a 4-week period.

1.2This test method can be used to evaluate the comparative resistance of interior coatings to accelerated mold growth. Performance at a certain rating does not imply any specific period of time for a fungal free coating. However, a better rated coating nearly always performs better in actual end use.

1.3Temperature and humidity must be effectively controlled within the relatively narrow limits specified in order for the chamber to function reproducibly during the short test period. Severity and rate of mold growth on a film is a function of the moisture content of both the film and the substrate. A relative humidity of >93 % at a temperature of 32.5 ± 1 °C (90 ± 2 °F ) is necessary to initiate and maintain mold growth and for test panels to develop rapidly and maintain an adequate moisture level to support mold growth.

1.4The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.

1.5This 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.

1.6This 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.