I met this guy, Troy Hurtubise, years ago in Ontario, as he lived in the same town as I did at the time, and there was only one real bar where everyone went to. He was trained in TKD and he had developed a Bear Proof suit ... I saw a documentary years later called `The Grizzly Project`` where he actually took on a Grizzly (movie trailer .. http://www.nfb.ca/film/project_grizzly/ )
Funny enough but CS gas doesn't work on dogs we use them and it doesn't effect them in any way. Also use when you have a cold or Sinus is blocked it clears the nasal passage very quickly.
Opening an umbrella at an oncoming dog freaks the hell out of them, although I`ve never had an issue with dogs ... it`s always those little yappers that I find amusing. CS gas for nasal issues ... wouldn`t that be like pouring hot sauce down your nose?
I have never carried spray with me and nobody every used it on me but i guess it's good for self defense if you don't have the training. I was thinking of getting one for myself but i have started training in NOGI now.