It’s a long overdue start but without explaining the purpose and effectiveness of the various filter elements the rest is pretty much useless. Been doing respiratory protection stuff from dozens of different angles, for at least six decades, and have most of the common equipment right here in the shop. It is so incredibly boring to always hear just pieces of the basic methods/problems/equipment spouted by people who obviously never read a book on the subject.
My business requires respirators for certain tasks. You can not just hand out a respirator including the N95 without following the regulatory guidelines. The State of California is violating its own rules