This standard specifies the environment parameters of mechanical products in heat and humidity areas and their severity grades. It is applicable to general-purpose mechanical products used in "heat and humidity" and "sub-heat and humidity" climate areas. Mainly related to Machinery widely used in agricultural machinery, internal combustion engines, Engineering machinery, etc. This standard does not apply to high-concentration chemical corrosion environment, ship and mine products. Through this standard, the adaptability of mechanical products in heat and humidity environment can be effectively evaluated, providing a clear reference for environmental conditions for product design, manufacture and application.