geez thats awfull learning the hard way. i quess you really dont know if your allergic or not . i would like to act like i am with anything i grind,sand,cut,polish,ect. i usually wear a respirator as second nature, i figure i smoke and am doing enough damage to myself that there is no sense in adding to the agony. i have seen qupote on quote men who say aaahh i dont need that mask or safety harness. i once knew a young man who nearly lost his life and i say nearly as an understatement, he was working construction on a dome type of structure, and beneath him they were laying rebarb for concrete slabs he was told to wear a safety harnesss after all this is a dome structure come on its common sense to wear a safety harness you would think well he decided it was less of a man if he wore one, well the rearb on the ground was sticking out about 3 foot just sticking up all over where the slabs were going well. he took the plunge and once he started it was too late he came down off that dome he landed on his feet alright,, with a 3 foot piece of rebarb planted in his bung hole. the rebarb travled straight up through his organs and missed spearing his heart by a fraction of an inch. the doctor told him the only thing that saved his life was his legs did not give out when he came down on that rebarb. the story ended with him having 2 bags permanantly attached to him for the rest of his life. he will never stand or sit on a toilet again he justs empties his bags. really nice kid he just made a bad decision. it was not a good sound hearing someone scream that just rammed a piece of rebarb of his fanny and i do mean directly up the shoot. some lifes ventures are just not meant to be learned the hard way i quess. at that time he was i think around 16 years old. i felt real bad for this kid.