Health officials in Contra Costa, Marin, Alameda, San Mateo and Sonoma counties made the announcement Friday afternoon as the virus continues to spread.
In addition to the five Bay Area counties, the cities of Fremont, Pleasant Hill and San Francisco have issued similar ordinances for residents, requiring the use of face masks in public areas like essential businesses, common spaces and when riding public transit.
RELATED: Coronavirus pandemic: Face coverings required in San Francisco starting at midnight
In San Francisco, the ordinance went into effect at midnight Friday, with police enforcement beginning April 22 at 8 a.m.
The city made an initial face mask recommendation on April 2.
Friday's ordinance makes face coverings a requirement for those living in or visiting the city.
In terms of what is considered a face covering, residents do not have to use an N-95 mask. A bandana, scarf, towel or homemade mask can also be used, San Francisco officials said.
Starting today, people in San Francisco are required to wear face coverings at essential businesses, in public facilities, on transit, and while performing essential work.— London Breed (@LondonBreed) April 17, 2020
This is not a replacement for staying home and physical distancing, but it is an important step for safety.
Contra Costa County
In Contra Costa County, the order goes into effect April 22. The East Bay county has similar guidelines as other parts of the Bay Area.
Workers and residents conducting essential business, visiting a health care facility or taking public transit must wear a mask or face covering.
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Children under the age of 12 are not required to wear a mask and those under 2-years-old must not wear a mask because of the risk of suffocation, officials emphasized.
To view the county's order, click here.
The face mask order in Marin County goes into effect April 22 and requires similar action by residents.
Beginning Friday, residents in Sonoma County must wear face coverings when out in public.
RELATED: Coronavirus impact: New ordinance requires Sonoma County residents to cover face in public to help prevent spread of COVID-19
Beginning at midnight Friday, residents in Alameda County will be required to wear masks. Enforcement will begin at 8 a.m. on April 22, county officials announced Friday.
To view the full order, click here.
San Mateo County
Effective at midnight Friday, residents in San Mateo County must wear a face covering. The order, announced Friday, will not be enforced until April 22 at 8 a.m.
To view the full public health order, click here.
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