California Proposes a 24-Hour PM2.5 Standard
The California Air Resources Board and the Office of Environmental Health Hazard Assessment have developed a draft proposal for a 24-hour PM2.5 standard of 25 ug/m3, not to be exceeded.
The move comes in response to the unanimous recommendation of the state’s Air Quality Advisory Committee, that the State adopt such a standard as part of its review and revision of the ambient air quality standards for particulate matter. The proposed level is far more stringent than the EPA standard of 65 ug/m3, 98th percentile, which allows 7 exceedances each year.
The public review draft of the proposal is available at: www.arb.ca.gov/research/aaqs/std-rs/pm25-draft/pm25-draft.htm.
The scientific basis for the proposal will be peer reviewed by the Air Quality Advisory Committee (AQAC) at a April 3 afternoon meeting in Oakland. See http://www.arb.ca.gov/research/aaqs/std-rs/aqac/AQAC_Meeting_Notice_031102.pdf
Written comments must be received by March 25, 2002 to be considered at the meeting. They may be sent to dmazzera@arb.ca.gov. Public comments will also be accepted at the meeting.
Following the AQAC meeting, the staff may revise the 24-hr PM2.5 proposal. A final staff report that includes the entire suite of recommended standards for PM2.5, PM10, and sulfates will be released for public review in early May. The Air Resources Board is scheduled to make a final decision at their June 20, 2002 meeting.
