1. It is a self-priming filtering personal protective equipment that can effectively protect the respiratory organs of the wearer from harmful gases, low-risk radioactive dust, and biological aerosols. 2. (1) Anti toxic time: Anti cyanide time: ≥ 30 minutes. (30L/min, 1.5mg/L, relative humidity: 80-80%) (2) Inhalation resistance: not greater than 180Pa under a constant airflow of 30L/min. (3) Exhalation resistance: not greater than 300Pa under a constant airflow of 160L/min.