Preliminary regional data for 2009 shows there was less pollution from ozone this year than at any time in the last decade, according to the Metropolitan Washington Air Quality Committee (MWAQC,) which monitors the area’s air quality. 

”On behalf of those of us who have been working for cleaner air, it is gratifying to see that programs implemented five years ago are finally showing results – though it is critical that we do not rest on our laurels,” said District of Columbia Councilmember At-Large Phil Mendelson, who serves as MWAQC Chairman.  “We must not pause in our drive to have cleaner, healthier air to breathe.”

Ozone, a ground-level pollutant that develops when emissions from vehicles and power plants mix with high temperatures, is regulated by the U.S. Environmental Protection Agency (EPA.)  From the beginning of May through mid-September, there were only four days when ozone pollution reached unhealthy levels for people with lung ailments, children and senior citizens. This compares with 17 such days in 2008 along with three additional days last year when ozone pollution made the air unhealthy for all area residents.

Air quality improved this year even though the EPA had set new, more stringent limits for the area’s ozone pollution.  When air quality is measured and considered at EPA’s Code Orange level, it is considered unhealthy for those with lung ailments, children and seniors.  A Code Red air quality day means the air is harmful for all residents. No Code Red days were observed in 2009.

MWAQC officials said this year’s air quality improvements resulted from actions taken over the last five to ten years to reduce emissions from vehicles and power plants, local government programs to increase ridership on public transit and buy energy from renewable sources, and milder than normal weather conditions.

Even though the region’s air quality has improved, the EPA again is considering adopting stricter health standards for ozone because many scientific studies now link much smaller amounts of ozone pollution to serious respiratory problems. EPA announced last week that the ozone standard adopted in 2008 (75 ppb) will be revised. MWAQC officials said they will recommend additional action to meet those tougher standards.