GB/T 2423.16-2022 "Environmental Testing - Part 2: Test Methods - Test J and Guidance: Mould Growth" was released in July 2022 and implemented in February 2023, replacing the previous edition and adopting the international standard equivalently. This standard specifies two mould growth test procedures, controlling a suitable environment for mould growth at (29±1)°C and (95±3)% RH, using eight representative mould species for inoculation, and evaluating the degree of mould growth on products through a five-level rating system. It is applicable to electrical and electronic products used in humid environments, focusing on assessing material resistance to mould and the impact of mould on product performance. It provides a unified basis for product anti-mould design, quality control, and market access in tropical regions.