SAN FRANCISCO (CBS SF) -- Less than a month after smoke-choked skies created apocalyptic landscapes across the Bay Area, the region was again blanketed with smoke from the Glass, Boysen and Shady fires in Napa and Sonoma County.
The Bay Area Air Quality Management District has extended a Spare the Air Alert because of the wildfire smoke through Friday. The district said wildfire smoke combined with high inland temperatures and vehicle exhaust may also cause unhealthy smog, or ozone, accumulation in the Bay Area.
No burning of wood, manufactured logs, or any solid fuel is allowed during the Spare the Air alert, whether indoors or outdoors.
Authorities in Napa and Sonoma counties alerted residents not in the fire zone Monday about visible smoke and light ash from the Glass Incident fires.
In San Francisco, the Department of Emergency Management said Monday the smoke from regional fires was impacting the city, urging people who are at risk to monitor the air quality.
"Smoke from the Glass Fire will continue to impact the region throughout the week," said Jack Broadbent, executive officer of the Air District in a press release Monday. "Residents should monitor air quality closely and avoid exposure if smoke reaches unhealthy levels."
"The air quality is bad, it makes your throat dry and whatever," said cyclist Brian Canali, who rode up Alum Rock Avenue. "I probably shouldn't be out here."
In the Santa Clara Valley, the air quality was listed as "moderate" which makes it unhealthy for sensitive groups.
Doug Lopes is a healthy 68-year-old trail runner. But he felt it today.
"You have trouble breathing. You can't take in as much air. So it's a little difficult," Lopes said.
"Smoke impacts are the biggest concern because it can have immediate health impacts. There's particulate matter, that's so fine, PM 2.5 which gets very deep into your lungs," said Tina Landis of the Bay Area Air Quality Management District. "If you have asthma or any respiratory issue, it can have immediate and long-term impacts."
The smoke and the heat prompted San Jose to open four cooling centers including one at the Vietnamese American Community Center on Lucretia Avenue so people can shelter indoors.
"Since these are not normal times, people can't do things they would normally, like going to the mall, going to the movies. So the cooling centers provide an air-conditioned space," said Charlotte Graham, a spokesperson for the City of San Jose.
The centers also provide water and free Wi-Fi. But as recurring emergency conditions seem to drag on and on, some are wondering "when" and even "if" it will end.
"The way these fires have been going on the past couple of years, I think this is the new normal. I'm worried about that," Canali said. "They say you're not supposed to go out in this, but people are starting to go out."
Elderly persons, children and individuals with respiratory illnesses are particularly susceptible to elevated air pollution levels and should take extra precautions to avoid exposure, the air quality district said.
Ozone pollution is particularly harmful for young children, seniors and those with respiratory and heart conditions, the district said. When a Spare the Air Alert is issued, outdoor exercise should be done only in the early morning hours when ozone concentrations are lower.
Len Ramirez contributed to this report.
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