By Amy Graff, SFGATE and Jenna Lyons
A series of deadly California wildfires have burned through some 170,000 acres statewide, but heavy smoke from the disaster zones drifted farther still as pesky particles of dust, ash and soot entered the lungs of residents nearly 100 miles away.
For the Bay Area especially, air quality has reached historically poor levels as the unhealthy atmosphere has already sickened residents, prompted medical calls to local schools and prompted the wearing of protective masks. In San Francisco, officials said two hospitals had about three or four patients each come in for respiratory issues that might have been related to the smoke.
But Wednesday's gusty, volatile winds -- bad for firefighters trying stop the spread of the fast-moving Wine Country wildfires -- was good for air quality as the gusts moved the block of smoky air sitting over the region.
Weather plays an important role when it comes to measuring air conditions, said Tom Flannigan, spokesman for the Bay Area Air Quality Management District.
"Air quality has improved throughout the Bay Area, which is wonderful. We've benefited from the sea breeze moving through the Golden Gate. Current readings have us mostly in the moderate range," Flannigan said Wednesday. "The readings have come down more than half compared to what we saw (Tuesday), in terms of air-quality-index readings."
Thick wood smoke from wildfires, leaving the air opaque and the sky shades of brown and yellow, resulted in the worst air quality ever recorded near the heart of the North Bay fires on Monday and Tuesday.
Still, hazardous levels reached as far south as San Mateo County, posing a risk to children, the elderly and those with respiratory conditions who, far away from the flames, may not have been on alert by the wildfires. An unhealthy air warning was issued as far as Redwood City, about 80 miles away from Sonoma County fires.
A number of medical calls from respiratory fatigue were made on Tuesday from schools in West Contra Costa Unified School District, which spans from Hercules to El Cerrito, said district spokesman Marcus Walton.
The district decided to close the schools on Thursday due to the bad air. Other school districts, including Pittsburg Unified and Mount Diablo Unified, were also closing schools Thursday.
Marissa Glidden, a fifth-grade teacher at Verde Elementary School in Richmond, said the ventilation system at her school was mistakenly never turned off Tuesday, which caused recycled air from outside to pervade classrooms. Then, Glidden said, the school district provided surgical masks, which health departments have warned are ineffective in protecting against smoke.
Those trying to protect themselves are advised to wear N95 masks to minimize smoke inhalation, according to air-quality officials.
As poor air quality persisted Tuesday, Glidden's students began signing out as some coughed, at least one student vomited, and a teacher in a classroom next door suffered an asthma attack. At least three students had to leave in an ambulance from Richmond High School, she said.
"It was miserable. It felt really bad as a teacher to try to protect your kids," said Glidden, who is vice president of United Teachers of Richmond union. "We're stuck in a smoky classroom with no communication about what to do."
The school board acknowledged the mask issue and plans to resolve the problem, Walton said. Glidden said Wednesday the ventilation was finally turned off at the school.
"We're lucky right now the air quality's OK," she said Wednesday. "But it's expected to get worse as the wind shifts."
The prediction lines up with air-quality forecasts. As winds continue moving, Friday and Saturday should see a return to poor air quality, Flannigan said.
"We're going to see that north wind pick up again tonight and into Thursday and that means drier, warmer air," Flannigan said Wednesday. "That means that it's going to push the smoke from these still burning fires from north to south, southward and across into different parts of the northern and central Bay Area. Places like Marin, East Bay, maybe even San Francisco, will see smoke again."
That means residents who smell smoke in the area should stay indoors with their windows closed and air conditioning units on recirculate to stop outside air from entering indoors, according to air quality management officials. Parents and school officials should pause before letting children outdoors. Meteorologists expect smoke to return in full force.
"We're going to see a really strong settling of the smoke in the Bay Area on Friday and Saturday," said Brian Garcia, a meteorologist with the National Weather Service. "Not to mince words: It's going to be really bad. It's not going to be fun."
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