ຂໍ້ມູນຄຸນນະພາບອາກາດສະໜອງໃຫ້ໂດຍ: the Bureau of Air Quality, Pennsylvania's Department of Environmental Protection (dep.pa.gov)
Note that the measurements for PM2.5 (fine particulate matter), PM10 (respirable particulate matter), O3 (ozone) and CO (carbon monoxide) are taken from the station: Liberty 2, Allegheny, Pennsylvania