As a result of a legal agreement with environmental groups, the Environmental Protection Agency has downgraded the smog pollution rating in portions of five states from “serious” to “severe.” The downgrade will trigger more protective measures to reduce the dangerous levels of smog pollution.
The areas affected have some of the nation’s worst air quality. The EPA downgraded the areas because their ground-level ozone pollution — commonly called smog — continues to exceed levels that are safe for human health, wildlife and plants.