If you insist upon riding when the air quality is bad or if you regularly ride next to major roads or freeways, you should consider riding with an anti-pollution mask. During “red” alerts the Bay Area Air Quality Management District suggests that people wear N95 masks. These masks block some of the particulate pollution but they don’t seal against your face and provide little barrier at all if they’re loose. They also have no exhalation ports so you exhale into the mask and rebreathe your breath. Needless to say during exercise they are not comfortable let alone wearing them when you’re walking outside. Their one saving grace is that they’re dirt cheap and can be purchased at any Home Depot or hardware shop.
What you should be wearing is a mask like the Respro Sportsta. Respro has been around for well over a decade but it’s based in the UK and is not well-known here. Respro makes anti-pollution masks for a variety of uses and the Sportsta is their model for cycling. They are made of neoprene and seal tightly against your face with a strap. They have an adjustable nose bridge so that you can fit the upper part of the mask perfectly against your face. They also have exhalation ports that open when you exhale and shut when you don’t. Finally they have replaceable HEPA filters so when your filter gets dirty it is easy to swap it out for a clean one. Unfortunately they’re not cheap: The Respro Sportsta costs about $45 and a two-pack of replacement filters is $25 on Amazon. You also have to size them to your face in order for them to work, so make sure you check the size chart on the Respro website.
I wear a size medium and with the Velcro-like strap I can get a tolerable yet tight fit. That doesn’t mean it’s comfortable—it’s not: wearing an elastric band around your face is never going to be as comfortable as a Wonderbra. But it’s not irritating either. Being able to exhale easily is a plus although in warm weather you are going to feel the extra insulation. If the temps are cooler, as they have been during the Camp Fire, it’s less uncomfortable.
Does it work? Hard to say because I’m coughing regardless right now with the air quality being so bad all day long. If you’re commuting to work, these masks work very well because you’re usually not breathing very hard. For recreational use they’re definitely better if you’re taking it easy, which is what you should be doing anyway with our abyssmal air quality. If you’re going á bloc they’re probably going to be quite uncomfortable as it was for me. But for getting in that not-so-fast recreational ride, the Respro is fine. Remember: these masks aren’t perfect so don’t imagine that you’re safe riding during bad air quality: you’re not. But they will reduce your exposure, you know, like getting less radiation after the H-bomb has been dropped. Hey, but you gotta get in your ride, right?