Sharing a little something about handling Procion dye, from the BOOKARTS mailing list. I thought this was actually a pretty good idea (about the clear container). I worry a little about the dye particulate because I know of people who have developed a sensitivity to it.
Here is advice given in the email:
(snip) I avoided fabric dyeing for years because the MSDS and general warnings were so terrifying. Let me reassure you that you can do this safely and sensibly - you have two options
1) Build a clear plexiglass box, or better yet, buy a large clear storage box such as they have at Walmart. Cut two round hand-sized holes in the side. When ready to dye, put the lid of the box on the counter upside-down, place damp paper towels all over it. Place on it the jar of dye powder, measuring spoon, empty jar with lid and measuring cup with water. Put the box on the lid upside-down. Put light-weight dust mask on if you want but I do not. Put on gloves.
Reach in holes and measure dye powder into jar, replace lid on powder, add water to other jar, put on lid, shake.
The whole point is to contain the dust and KEEP IT FROM BLOWING AROUND! We do NOT want good ventilation here, we want stillness! Keep doors and windows closed.
You will be gratified to see lots and lots of little specks of dye on the damp paper towel - once they light there they are no longer a risk for you to inhale them. The dye that is now in the jar with water is no risk to you at all - wearing gloves is to avoid serious changes in our skin color and on general principal to avoid absorption through your skin.
2) I no longer use the box - I set up everything in a room with all windows and doors closed so there is no draft, I spread out damp paper towels over a three foot square area and I go to work. I do wear the light - weight dust mask and gloves. In my experience the dye/dust specks all turn up well within the 3 ft perimeter of damp towels, which tells me there aren't any floating freely around the room. When done I wipe every surface with damp towels. That's it.
This all sounds much more complicated than it really is - just focus on containing the dust and using damp everywhere. The rewards are multitudinous and marvelous - dye everything with plant origin (cotton, wood pulp, linen, rayon) including paper and your own book cloth!!
Good Luck, Henrietta in Blue Hill, Maine