This standard is one of the environmental test methods in the series for optical and photonic instruments, specifically regulating the testing methods for the ability of instruments and their components to resist the effects of contamination. Here, "contamination" specifically refers to the exposure of instruments to corrosive chemical substances, with the aim of evaluating the resistance of their surfaces, coatings, and synthetic materials to such reagents. This method applies to optical instruments and related components from other fields (such as mechanical and electronic equipment), primarily for material screening and design verification rather than routine production control. During the test, representative samples are typically exposed to specific chemical reagents under controlled conditions. Related testing instruments may include test chambers or containers used to create and maintain the test environment. This standard is a modified adoption of the corresponding international standard and provides a crucial basis for evaluating the reliability of products in contaminated environments.