PPE that can withstand molten slag from arc flash
Go to a welding supply, buy leathers. They will stand more abuse than most other things, but they are also a consumable, meaning you need to replace them as they become damaged in use (upside - welding leathers are usually not terribly expensive, as leather goods go.) The "cape sleeve and bib" is a good combo if you only need protection from the front, in warmer weather.

Be careful what sort / style of footwear you choose - a common error which tends to become a learning experience when cutting steel (lots of molten slag) is having footwear which does not shed incoming slag onto the floor - either because you've tucked the pants into it (don't) or because the tongue of a lace-up boot is arranged in a way that allows slag to collect and slip into the boot, following which the occupant of the boot has a strong interest in removing it as fast as possible, and different boots. Or the old "wearing fabric boots that melt" problem (or sneakers for the more foolish) or low-top shoes rather than boots.