2023年3月29日 — Currently, EPA has primary and secondary standards for PM2.5 (annual average standards with levels of 12.0 µg/m3 and 15.0 µg/m3, respectively; ...
2023年10月31日 — The Clean Air Act requires EPA to set national air quality standards for particulate matter and five other pollutants considered harmful to ...
2023年10月17日 — Announcements. 1/6/2023 - EPA announces proposed decision to revise primary annual air quality standard for fine particle pollution (PM2.5).
2023年11月1日 — PM2.5 describes fine inhalable particles, with diameters that are generally 2.5 micrometers and smaller. Under the Clean Air Act, EPA sets and ...
2023年7月11日 — PM2.5 : fine inhalable particles, with diameters that are generally ... EPA regulates inhalable particles. Particles of sand and large dust ...