DT-2021 intelligent dual-channel constant-current atmospheric sampler (hereinafter referred to as sampler) is mainly used to collect formaldehyde, ammonia, TVOC, benzene and other gases in the air. The sampler meets the requirements of GB50325-2020 Indoor Environmental Pollution Control Standard for Civil Building Engineering and GB/T18883-2022 Indoor Air Quality Standard. The product has stable performance and convenient operation. It is suitable for indoor testing, environmental monitoring, industrial and mining enterprises and health and epidemic prevention departments to collect all kinds of toxic and harmful gases.