once traind in the "safe use " thats it,, city and guilds in playing with tabs ?? lol..it has its uses, i get asked to use it at a few places,,, not my cup of tea but i agree even tho i disagree,,,, its nasty stuff tho ,, it stinks on my kit and i dont like it, the germans used to shower the jews in they camps and as they did there were a few tabs droped in the shower area,,thats what they used to gas them with ,,, its nasty kit so be caerfull.