They should report these unsafe working conditions to OSHA. Hospitals are required to have a plan for this, and certain actions are specifically called out as potentially riskier. Seems like if you've notified the administration of the risk, and notified OSHA you can stop work until the dangerous work environment is resolved. Findlaw and OHSA article on respiratory programs below.

Under federal and state laws, employers must provide a safe workplace. If unsafe working conditions are present, a worker may report the violation to the employer, to the federal and/or state Occupational Safety and Health Administration (OSHA), and in some cases, the worker may refuse to work. The following is a summary of OSHA protection and guidelines for dealing with dangerous conditions in the workplace. What to Do When a Safety Hazard Poses an Imminent Danger When unsafe working conditions place the life of a worker in imminent danger, the worker should report the dangerous condition to OSHA. The worker also has the right to refuse to work if: There is a reasonable and good faith belief that a condition in the workplace poses an immediate and substantial risk of serious physical injury or death;

https://employment.findlaw.com/workplace-safety/protecting-y...

https://www.osha.gov/Publications/OSHA3767.pdf?fbclid=IwAR0r...