The scenario: you're riding in a curb-adjacent, paint-only bike lane. You happen to look over your shoulder (or in your mirror) and see a vehicle approaching from behind, either fully in the bike ...
I'm using my bicycle to ride from home to work and back. Now I face a problem that the air is not so clean: dust, car exhaust etc. So I'm thinking of buying a respirator (i.e., an anti-pollution ...