Facing the double whammy of ozone and smoke, air quality leaders have declared the second air-pollution alert of summer for the San Joaquin Valley from Stockton to Bakersfield.
The alert will run through Wednesday as the region swelters in temperatures forecast above 100 degrees with only light breezes -- conditions that lead to corrosive ozone pollution.
The sprawling Rim fire in Stanislaus National Forest and Yosemite National Park also is sending smoke and ozone-making gases into the Valley. At 253,332 acres, the fire is the third largest on record in California.
People with heart and lung problems should stay indoors when smoke and ozone are spiking, health authorities say. Residents are urged to follow air quality developments in their area on the San Joaquin Valley Air Pollution District’s online reporting system.
Dr. A.M. Aminian, a long-time allergist in Fresno, said his patient load increased Monday, as people with asthma and other lung problems came in for treatment. He said the smoke, ozone and heat are aggravating symptoms.
"I advise people to take a shower when they get home from work to get all the particles off them," Aminian said. "Remember to push the recirculation button in your car so you don't get outside air. And anyone having a lung problem shouldn't let it go too far. See a doctor."
In these conditions, the ozone readings could climb above the federal one-hour threshold for the first time this summer, say district leaders.
Last month as traffic picked up for school, the district announced the season's first alert, which are only warnings and carry no mandatory restrictions. The one-hour standard was not breached.
If the air basin gets through the warm season without exceeding the one-hour standard, it would end a $29 million annual penalty. The penalty is paid mostly by motorists in registration fees.
Air district leaders urge residents to carpool and cut down on other ozone-making activities, such as using gasoline-powered lawn equipment or idling at drive-through services.
"We are at an extremely critical point in our journey to meet this standard," said Seyed Sadredin, the district's executive director.
The Valley has exceeded the more health-protective federal eight-hour ozone standard for five days in a row, though this summer has not been as bad as most. The region has breached the eight-hour standard 75 times this summer. The goal is to eliminate the exceedances.
September is known for sudden ozone spikes in the Valley. In 2011, ozone exceeded the one-hour standard four times -- the last of which was on Sept. 29 that year.
Air-quality leaders say the Valley this summer has a big opportunity to finally achieve the one-hour standard and end the annual penalty, which began two years ago.
"As we get nearer to the end of ozone season, it becomes even more important to avoid an exceedance," Sadredin said.
• Shower after work to wash off particles
• Use a nasal rinse
• Push recirculation button in car's air conditioning system
• Don't miss prescribed medications
• See a doctor if cough or lung problems persist
Check back later for more on this developing story.
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