Fires are dangerously polluting California’s air. Some cities are handing out masks

The fires burning across California are not only destroying homes and sending people fleeing from flames, but also creating dangerously poor air quality even for those not directly affected by the blazes.

Many Californians, some as many as a hundred miles from a fire, report thick, gray air in their neighborhoods. School was canceled in some areas because of the smoke, as the danger is worse in places where smoke is visible.

But even when the air feels clear, pollution can enter the bloodstream and cause damage, doctors say. It’s often only people with asthma or other health problems who will cough or sneeze amid these conditions, though everyone experiences the harm.

While three major wildfires burn up and down the state, health officials advise residents not to go outdoors unless absolutely necessary and to turn on air conditioning to circulate air indoors. Cities damaged by fire are most at risk.

“It is difficult to tell where ash or soot from a fire will go, or how winds will affect the level of dust particles in the air, so we ask everyone to be aware of their immediate environment and to take actions to safeguard their health,” said Dr. Muntu Davis, Los Angeles County health officer.

In Los Angeles County, the areas with the worst air quality Saturday were the west San Fernando Valley and northwest coastal Los Angeles County, according to Davis. The air in these regions is considered unhealthy for everyone, not just people who are sensitive to pollution.

This site shows real-time air quality conditions for locations statewide.

By Saturday, the Woolsey fire had exploded to 70,000 acres and forced the evacuation of 250,000 homes across Los Angeles and Ventura counties. Two deaths have also been reported.

The worst air quality in Ventura County is in Thousand Oaks, where several homes have burned, followed by Moorpark and Camarillo, according to the Ventura County Air Pollution Control District.

The Camp fire in Butte County north of Sacramento has claimed at least nine lives and destroyed more than 6,700 structures, as it leveled the town of Paradise, a popular retirement community that sits along a ridge in the Sierra Nevada foothills. The fire has made the Bay Area and the surrounding region home to some of the worst air quality in the state.

South San Francisco and Daly City began handing out masks to residents. One group is raising money to hand out masks in Oakland, where air quality levels are unhealthy.

The most effective masks are known as N95 or N100 respirator masks, which filter out fine particles and are typically sold at hardware stores. Surgical masks don’t protect people from harmful particles.

The San Francisco Business Times reported Friday that several stores in the city sold out of masks due to high demand, and San Francisco Curbed created a list of places to still find them in the Bay Area.

Starting Thursday, the Bay Area Air Quality Management District banned burning wood indoors or outdoors because of the fires. The ban will last at least through Monday.

“Air quality throughout the Bay Area and especially in the North Bay is being heavily impacted by smoke from the fire in Butte County and use of fireplaces tonight and tomorrow will make air quality conditions worse,” Jack Broadbent, chief executive of the air district, said in a statement.

soumya.karlamangla@latimes.com

Twitter: @skarlamangla