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SAN FRANCISCO (KTVU) -- Air quality officials on Thursday issued a Spare the Air smog alert for Friday, the 18th such day this season.
Friday's designation follows a similar alert for Thursday because of light winds and smoke from nearby wildfires, which are expected to mix with vehicle emissions.
The smog could impact Bay Area residents because it has been linked to throat irritation, congestion, chest pain, asthma, inflammation of the lining of the lungs and worsen bronchitis and emphysema.
“Ongoing smoke continues to impact air quality in the Bay Area,” said Jack Broadbent, executive officer of the Air District. “Persistent drought and tree mortality has increased the intensity of wildfires in the region, and combined with our daily load of auto exhaust, is again causing unhealthy air quality.”
Residents were urged to use mass transit or bike, walk or carpool to work instead of driving alone in their vehicles.