In an effort to help citizens avoid very unhealthy air, prompted by the ongoing Camp Fire, Muni will let people ride free of charge Friday.

The smoke-laden air has blanketed most of San Francisco this week, culminating today’s horrendous score of 221 on the EPA’s 500-point Air Quality Index [AQI]. Free Muni rides will help keep people from exerting themselves by walking. It will also limit time outside for many passengers.

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“If you can see, taste, or feel smoke, you should immediately avoid or minimize outdoor activities, or travel to a location not affected by smoke, if you can,” warns SF72. “This is especially important if you have health concerns, are elderly, pregnant, or have a child in your care.”

Mayor London Breed reportedly called for free Muni today.

In another effort to help keep denizens healthy amid the haze, San Francisco Parks and Recreation will keep centers across the city open. Also open today are all libraries, museums (some of which have free-Friday entrance today), and indoor shopping malls.

Here’s a list of places open to the public to escape from the very unhealthy air today. Be sure to check the hours of operation for each facility before you go.

Chinatown Branch Library: 1135 Powell Street

Glen Park Branch Library: 2825 Diamond Street

Mission Bay Library: 960 Fourth Street

San Francisco Main Library: 100 Larkin Street

Westfield San Francisco Centre: 865 Market Street

Japantown Center Malls: 1737 Post Street

Stonestown Galleria: 3251 20th Avenue

Dr. George W. Davis Senior Center: 1751 Carroll Avenue

Asian Art Museum : 200 Larkin Street

SFMOMA : 151 3rd Street

De Young Museum : 50 Hagiwara Tea Garden

Betty Ong Recreation Center: 1199 Mason

Bernal Heights Recreation Center: 500 Moultrie

Eureka Valley Recreation Center: 100 Collingwood

Gene Friend Recreation Center: 270 Sixth Street

Glen Park Recreation Center: Bosworth ad O’Shaughnessy

Golden Gate Park Senior Center: 6101 Fulton

Hamilton Recreation Center: 1900 Geary

Harvey Milk Photo Center: 50 Scott

Joseph Lee Recreation Center: 1395 Mendell

Minnie and Lovie Ward Recreation Center: 650 Capitol

Mission Art Center: 745 Treat Avenue

Mission Recreation Center: 2450 Harrison

Moscone Recreation Center: 1800 Chestnut

Palega Recreation Center: 500 Felton

Potrero Hill Recreation Center: 801 Arkansas

Randall Museum: 199 Museum Way

Richmond Recreation Center: 251 18th Avenue

Sharon Art Studio: Sharon Meadow

St. Mary’s Recreation Center: Murray and Justin

Sunset Recreation Center: 2201 Lawton

Tenderloin Recreation Center (17 and under only): 570 Ellis

Upper Noe Recreation Center: Day and Sanchez

Here’s a map of all the indoor locations with filtered air:

Update: Oakland Mayor Libby Schaaf tweeted a list of public spaces with air filtration., which include all Oakland’s libraries, senior centers, and other city facilities.