I am also very sensitive to some perfumes. The ones that smell fruity are OK, as are things that smell like pine. I can even deal fine with some incense and oils. But there are some scents, to me they feel "sharp," the really strong flowered scents, that can cause me to be almost instantly ill. They are far worse than cigarette smoke or fuel fumes.
When I run into one of those horrible scents, I instantly get a headache and the beginnings of an asthma attack. Then my sinuses, my throat, and the tubes to my ears start to itch intensely. After that, it starts to bother my mouth, and I end up with a horrible toothache on top of everything else. By this point, my nose is running uncontrollably and I'm force to stay in my office with a box of Kleenex until I get it under some control. It usually takes 3 or 4 ibuprofen to chill the pain. I wish I could take a Benadryl or something for the rest of it, but every antihistamine I've tried puts me to sleep...even the non-drowsy stuff. I can't do that at work!!
We used to have a housekeeper that didn't bathe often, so dumped on perfume instead. I could literally smell her when she got off the elevator on our floor. My only defense was to open my window...and then leave the floor for about an hour. Thankfully, I have a secondary office in another building that I use when I'm working on the machines in that building, and could go over there for a while. If I was off the floor within 5 or 6 minutes of her arrival, my symptoms would be mostly gone by the end of the hour.
Now, after all that, I'm not at all sure I'd call this a "disability." It's no worse than hayfever. In fact, for me at least, it's essentially the same thing. I do think it's just common courtesy for people to take care that they don't stink in public...in any way. And employers should enforce some hygiene rules about all types of scents. However, calling it a disability or suing over it is way overboard.
I wonder if anyone has ever developed an anti-perfume spray? Hmmmm....