@OnfromGambier @Bewickwren During Oregon fires a couple of years ago this was a lifesaver for my friend living there. AQI was like 500. Comercial HEPA filter did almost nothing even with all windows closed (too small). CR box cleaned up the air in the entire house.
@几年前俄勒冈州火灾期间，这是我住在那里的朋友的救命稻草。AQI大约是500。Comercial HEPA过滤器即使在所有窗户都关闭（太小）的情况下也几乎不起任何作用。CR-box净化了整个房间的空气。