Brake Cleaner and Welding. Just say no.

     Hobbyist or professional, if you weld, then you better know not to pre-clean your parts with brake cleaner. Basically a chemical reaction between the chemicals in brake cleaner (not only brake cleaner) and argon gas creates phosgene gas. And it'll kill ya dead. Don't take my word for it, let Baldey McSoulpatch teach your ass some science. Safety 1st: Pre-Cleaning for Welding

Better learn how to read.