Don’t Bike When the Air Is Smoky

Government officials are warning people to avoid outdoor activities (see above map) due to particulates in the air. The media is full of reports and interviews with experts about the hazards of breathing the smoke. Many schools are closed. The San Francisco Bicycle Coalition has cancelled or postponed several outdoor events, including its pop-up outreach, and its AIDS/Lifecycle Kickoff ride.

Air quality experts are warning against bike riding altogether. Many cyclists have decided to take Muni. Apparently, that's causing huge delays.

In an interview with KRON4, Dr. Robert Blount, an assistant professor of pediatric and adult pulmonology and critical care medicine at UC San Francisco, recommended that if you have to go outside--to bike to work, for example--make sure to wear a tight-fitting "N95" mask, which means it blocks out 95 percent of particulates in the air. It should be certified with a stamp from the National Institute for Occupational Safety and Health (NIOSH). A kerchief or a run-of-the-mill dust or surgical mask won't due--only "N95 masks, when used properly, help filter fine particulates in wildfire smoke," wrote David C. Ralston, with the Bay Area Air Quality Management District, in an email to Streetsblog.

To be clear though, nobody is recommending you ride your bike, even with a mask, if there's any way to avoid it. "The N95 might be good if there's nothing else you can do, but it's not a great solution. It's not designed for people doing exercise or sports. It's meant for slow, regular breathing," said Ralph Borrmann, also with the Bay Area Air Quality Managment District. Studies show that keeping your speed and exertion levels down helps--so if you absolutely have to ride, try to stay under 11 mph and avoid hills.

Streetsblog Los Angeles, a city that knows a thing or three about dirty air, has some additional thoughts on cycling and smokey conditions back from 2009, when they suffered their last round of punishing fires. It too advises cyclists, at least when the air is this smokey, to leave the bike at home.

"I would normally ride my bike to work. I took the train instead," said Borrmann.