The US Environmental Protection Agency (EPA) has established a new national air quality standard for nitrogen oxide in an effort to reduce the respiratory infections that are linked to the emissions.
Under the new terms, the one-hour standard for NO2 is set at 100 parts per billion – this is the maximum allowable concentration anywhere in an area – while the EPA is also retaining the annual average standard of 53ppb.
Short term exposures to NO2 have been linked to respiratory infections, particularly among people with asthma; and it is said to contribute to the formation of fine particle pollution and smog. It is formed from vehicle, power plant and other emissions.
New monitoring requirements will be introduced in urban areas that will measure NO2 levels around major roads and across the community – they must be located near roadways in cities with at least 500,000 residents; while larger cities and areas will have additional monitors.
It is expected that the EPA will establish at least 40 monitors to help protect communities and it is expected to identify areas that don’t meet the standard by January 2012.
