Smoke from four wildfires raging across Southern California has resulted in unhealthy air quality across the San Fernando Valley, along with coastal areas and surrounding portions of Los Angeles County.
All people in those areas should avoid unnecessary outdoor exposure and limit all physical exertion, said Dr. Jeffrey Gunzenhauser, the county's interim health officer.
"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 all individuals to be aware of their immediate environment and take actions to safeguard their health," Gunzenhauser said.
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"Smoke and ash can be harmful,'' Gunzenhauser said, especially for vulnerable individuals, such as the elderly, children, people with asthma or individuals with other respiratory or heart conditions.
Throughout the county, sensitive individuals should stay indoors as much as possible -- even in areas where smoke, soot, or ash cannot be seen or there is no odor of smoke, Gunzenhauser said.
"We are also advising schools that are in session in smoke-impacted areas to suspend outside physical activities, including physical education and after-school sports, until conditions improve,'' Gunzenhauser said.
People can participate in indoor sports or other strenuous activity in areas with visible smoke, soot, or ash, provided the indoor location has air conditioning that does not draw air from the outside and has closed windows and doors, Gunzenhauser said.
"If you see or smell smoke, or see a lot of particles and ash in the air, avoid unnecessary outdoor activity to limit your exposure to harmful air,'' Gunzenhauser said.
If outdoor air is bad, try to keep indoor air as clean as possible by keeping windows and doors closed. Air conditioners that re-circulate air within the home can help filter out harmful particles. People were urged to avoid using air conditioning units that only draw in air from the outside or that do not have a re-circulating option. And residents were advised to check the filters on their air conditioners and replace them regularly.
Residents in affected areas should also keep their pets inside.