Can I sue my employer for the work-related diseases I sustained over the years?

My job requires us to clean robot cells in a factory that are filled with dust, dirt, and rust. They expect us to clean them with brooms which sends the dust and rust into the air. This wouldn't be so bad except the dust masks they provided us with are not effective against that much dust. I brought this problem up at a safety committee meeting and my employers agreed that the provided dust masks were unacceptable and started giving us a better dust mask, however this is a multi-billion dollar company with contracts all over the world, and it took them nearly six years to provide us with the proper protective equipment. Since I have started working there I've had bronchitis, pneumonia, and bronchial pneumonitis. All of which caused me to miss work, and I was seen by a doctor for. I received a doctor's note for each occurrence, excusing me from my time off work. However, my employers have a point system and I was disciplined regardless of my doctors orders not to work in those conditions. I have received multiple suspensions and am currently on the verge of termination. What should my next move be?