3M Half Facepiece Reusable Respirator Assembly Kit 6391, Size Large, P100, Lightweight, Comfortable, Easy to Adjust, Includes 2091 Particulate Filter, Welding, Soldering, Asbestos

Most do. This is what I recommend: https://www.amazon.com/3M-Facepiece-Respirator-Respiratory-Protection/dp/B001NDN29O The box stores might not sell that particular configuration with the pancake filters. 3M says that the large size covers like 80% of the population, so get that unless you're an outlier.

Your boss is a dork. If my workers want a mask, then I get them a mask. Amazon sells respirators for very cheap. Just buy one, use it, and move on. https://www.amazon.com/3M-Facepiece-Respirator-Respiratory-Protection/dp/B001NDN29O/ref=sr_1_4