Q. Our air tests show that our powder coaters do not need air supply hoods at the area of application. We require them to wear a paper mask for protection. What is the best respiratory practice for this process?—J.C.
A. Powder is characterized as a nuisance dust and should not be inhaled. Typically, a dust mask or particle mask with a Class N95 filter approved by the National Institute for Occupational Safety & Health (NIOSH) is acceptable when handling powder, cleaning the powder booth or spraying through a window in the booth wall. When the operator is spraying powder inside the booth, he is supposed to have a fresh air supply because the concentration of dust is much higher. He should have a NIOSH-approved hood and suit that is fed with filtered air. You can find the filtering systems at a good paint supply distribution company or online. Cartridge-style filtered respirators are designed for vapors and are not as good an option for powder coating.