Here's a map of PM2.5 levels in San Francisco for those interested: https://hoodline.com/2015/04/should-you-be-worried-about-air-pollution-in-your-neighborhood

Here's a map of PM2.5 levels in San Francisco for those interested: https://hoodline.com/2015/04/should-you-be-worried-about-air-pollution-in-your-neighborhood https://hoodline.com/2015/04/should-you-be-worried-about-air...