The Environmental Protection Agency today released details of new regulations targeting nitrogen dioxide, a leading cause of smog that is created in part by vehicle emissions.
N02 exposure is linked to respiratory illnesses such as asthma, especially in children. Scientific research has shown that exposure to NO2 ranging from only 30 minutes to 24 hours can increase adverse respiratory effects in those with both healthy and unhealthy lungs. In addition to vehicles, NO2 is also formed by power plant and other industrial emissions.
The National Resource Defense Council has recommended in the past that school districts utilize alternative fuels such as CNG or propane that emit lower levels of nitrogen dioxide.
EPA Administrator Lisa Jackson earlier this month said lowering NO2 emissions levels is a main objective of the current administration’s efforts to strengthen te nation’s smog standards.
The new rule is the first of its kind for NO2 in more than 35 years. It was first proposed in September 2009. Since 1980, NO2 levels have dropped by more than 40 percent, according to EPA data. Today’s ruling follows 2004 Tier-2 emissions standards for light-duty vehicles and 2007 and 2010 standards for reducing nitrogen oxides (NOx) in medium- and heavy-duty diesel engines.
While retaining the existing annual average standard for NO2 of 53 parts per billion, EPA added a new one-hour standard for NO2 at a level of 100 ppb, and it will require by 2013 that at least 40 new monitors be installed near roadways in cities with populations of at least 500,000, where NO2 concentrations have been measured to be 30- to 100-percent higher than away from roadways. Meanwhile, in-vehicle concentrations of NO2 can be two to three times higher than at roadside monitors.
Currently, only population centers of 1 million or more in California have similar monitoring systems in place for NO2 non-attainment areas. The new rule will also identify and designate areas of the country not meeting the new standard by 2012. The new NO2 rules also fall under State Implementation Plans required under the Clean Air Act for adopting monitoring programs, calculations and forecasting of emissions levels, inventory of emissions, control strategy studies, adopting formal measures to reduce emissions, and evaluating achievements.
