EPA proposes new 1-hour SO_2 limits

摘要

Federal regulators have proposed new limits on short-term, hourly SO_2 emissions that would surpass the existing annual and 24-hour standards. The Environmental Protection Agency has proposed a 1-hour National Ambient Air Quality Standard (NAAQS) that ranges between 50-100 parts per billion (ppb) of SO_2, a limit more stringent than the 140ppb standard of the 24-hour SO_2 NAAQS already in place. The new standards are in response to recent studies showing a causal link for respiratory mortality after short-term exposure to SO_2.