Notes on NFPA 33

Recently a client wanted to know why he had to ventilate his paint booth outdoors instead of back into the building. Off the top of my head I told him that it was a safety issue more than an environmental issue, and that the concentration of flammable vapors should not exceed 25% of the Lower Flammability Limit (LFL). This answer was only partially correct. Recently I viewed NFPA 33 (Spray Application Using Flammable or Combustible Materials 2007 ). This publication, and many others, as well as … [Read more...]