Cleaning the lab could entail a knowledge of safety procedures, depending on the task, but chem majors don’t have all that memorized either. That’s what the MSDS info is for. My son as a high schooler worked in a chemical lab one summer and had no trouble performing the required tasks safely. (Heck, if we believe the anecdotes on CC,many high school kids work in labs and perform complex graduate level research to boot.) That said, my point was that a lab won’t generally hire someone who doesn’t have a relevant major (unless there’s some nepotism involved), so no one need worry about the potential danger.