I work in retail on the worlds busiest street, we get a lot of smelly people in our store, generally speaking theres a few whom make us all run for cover and a regular old guy whose lame and going blind comes in every day and hobbles about he stinks so bad I hold my breath from the minute I see him to the minute I've reached a minimum safe distance of at least 40ft. I've done this breathing in or out if I see him or catch his tang in the air I stop respirating mid breathing cycle