2024-11-22 GB/T 20738-2018 'Rooftop Air-Conditioning Unit' is a national standard officially implemented by China's State Administration for Market Regulation and China's National Standardization Administration on December 1, 2018. This standard aims to specify the technical requirements, test methods, inspection rules, marking, packaging, transportation and storage requirements for rooftop air-conditioning units to ensure product performance, safety and quality.