EPA proposes new ozone standards

Jun 21, 2007

The U.S. Environmental Protection Agency announced a proposal Thursday to strengthen the nation's air quality standard for ground-level ozone.

The EPA recommended an ozone standard within a range of 0.070 to 0.075 parts per million, as well as soliciting comments on alternative standards within a range from 0.060 ppm up to the level of the current 8-hour ozone standard, of 0.08 ppm.

EPA scientists said ground-level ozone -- the primary component of smog -- is not emitted directly into the air but is created through a reaction of nitrogen oxides and volatile organic compound emissions in the presence of sunlight. Major man-made sources include emissions from industrial facilities, electric utilities, motor vehicle exhaust, gasoline vapors, and chemical solvents'

The EPA also proposed revising the "secondary" standard for ozone to improve protection for plants, trees and crops during the growing season. The secondary standard is based on scientific evidence indicating exposure to even low levels of ozone can damage vegetation.

The agency said it will have public hearings on its proposals: Aug. 30 in Los Angeles and Philadelphia and Sept. 5 in Chicago and Houston.

Copyright 2007 by United Press International

Explore further: Despite significant reduction in smog-producing toxins, the Greater Toronto Area still violates ozone standards

add to favorites email to friend print save as pdf

Related Stories

Major air pollution studies to converge over Denver

Jul 04, 2014

Two NASA aircraft are participating in field campaigns beginning this month in Colorado that will probe the factors leading to unhealthy air quality conditions and improve the ability to diagnose air quality ...

What's in your air?

May 09, 2014

Every senior at MIT has come to know the campus in a personal way, having established favorite haunts for studying, eating, resting, and playing during their four years at the Institute. But the Course 1 ...

Recommended for you

Coal gas boom in China holds climate change risks

2 hours ago

Deep in the hilly grasslands of remote Inner Mongolia, twin smoke stacks rise more than 200 feet into the sky, their steam and sulfur billowing over herds of sheep and cattle. Both day and night, the rumble ...

Water crisis threatens thirsty Sao Paulo

10 hours ago

Sao Paulo is thirsty. A severe drought is hitting Brazil's largest city and thriving economic capital with no end in sight, threatening the municipal water supply to millions of people.

User comments : 0