I was in the same company as this guy who was allergic to metal,
ammo etc. No, I am not making this up. One other guy, was
apparently allergic to staying-in. Yep, even during BMT he was
allowed to go home everyday. 
The ones allergic to the SAF uniform were the funniest. You'd see
them going fo range with helmet, SBO, worn over PT attire. They
looked ridiculous! 