Written and posted by BAAQMD, January 2011.
Air quality in the Bay Area has improved significantly in recent
years due to tight regulation of emissions from all sources,
including industrial facilities and motor vehicles. Smoggy days
have declined substantially over the past 40 years. Despite this
progress, the Bay Area continues to exceed state and/or national
standards for ozone (smog) and particulate matter (PM) on a
limited number of days each year.
