Pointing Finger of Blame Toward Source of Smog : Environment: Downwind cities will no longer be held responsible for smog they inherit from an upwind neighbor, under new guidelines by the state air board.

In an attempt to find a more equitable way to measure whose smog is whose, the state Air Resources Board approved a policy resolution Friday that will hold regions accountable for the air pollution they generate, even after the smog has traveled miles from home.

Beginning immediately, the state will no longer hold downwind areas, such as San Diego and the San Joaquin Valley, responsible for the “transport” smog they inherit from their upwind neighbors, such as Los Angeles and San Francisco.

Instead, the resolution urges those air quality districts that have an overwhelming or significant impact on their neighbors’ poor air quality to develop strategies to reduce and mitigate transport smog. Among the strategies that the resolution deems reasonable: retrofitting stationary sources of pollution and creating permit programs that prevent increases in ozone-depleting emissions from new or modified facilities.

According to Jerry Martin, a spokesman for the state board, the state’s 41 air-quality districts will now consider the board’s resolution and set about developing specific strategies. The resolution describes these strategies as “necessary to achieve the state ambient air-quality standard for ozone, by the earliest practicable date.”

Friday’s action reaffirms a part of the California Clean Air Act that requires regions to take their neighbors into consideration when implementing smog-reducing regulations. In the act, regional districts are asked to be good neighbors and impose extra controls, if necessary, to keep their pollution out of someone else’s back yard.

Bob Goggin, a spokesman for the San Diego County Air Pollution Control District, called the policy “significant” because it will clarify “who is responsible for what.” By the APCD’s own measure, 41 of the 55 days that San Diego County exceeded federal air-quality standards in 1989 were caused by smog blown south from Los Angeles. Of the 158 days that San Diego exceeded state standards, Goggin estimated 62 could be blamed on Los Angeles.

Under the policy, smoggy San Diego days judged to be caused by Los Angeles smog would not be counted as days that San Diego exceeded air-quality standards. The result would put less pressure on San Diego County to impose stricter smog-control measures.

Although the pollution on those days would be racked up to Los Angeles, it also is unlikely that the new policy would mean stricter standards in that area, Goggin said. Los Angeles already has the strictest air-quality plan in the nation, he said.

“They’re already doing what they can. They’re not going to make their plan any tougher,” Goggin said. “The policy just recognizes that they have the responsibility.”

The resolution, which specifies 14 sites around the state where trans-boundary smog has been identified as a significant source of air pollution, likely will have a greater impact on areas that have not yet completed their air-quality plans or areas where transport smog is responsible for most smoggy days.

Martin said San Luis Obispo County, for example, which never violates federal standards and only rarely exceeds stricter state caps, could benefit greatly if its neighbors adopted stricter control measures.

The problem goes far beyond San Diego. San Bernardino, Riverside and Palm Springs have all inherited pollution generated along the Los Angeles County coast. Los Angeles smog has been measured by scientists at Death Valley and the Grand Canyon. One study spotted California smog as far away as Colorado.