Pennsylvania
Canada wildfires cause historically bad air quality in Pennsylvania
Pennsylanians experienced some of the worst air quality of the past 40 years this week, thanks to the smoke wafting across the northeast from intense Canadian wildfires.
There have been just five times since 1980 that daily Air Quality Index scores — a gauge devised by the EPA in the 1970s to give the public some plain-English context for pollution levels — have soared above 300, defined as a level hazardous to everyone’s health.