In a report released this morning, the association said the Washington region has the 14th highest ozone (smog) levels in the country. Arlington itself was slightly less polluted than the District, with an average of 9.8 ‘high ozone’ days compared to 10.7 days in the District.
The average number of high ozone days in Arlington has been been falling steadily since reaching a high of 32 from 1997 to 1999 (see chart, left).