History of U.S. Respirator Approval (Continued) - Gas masks, Supplied-air respirators, and Chemical cartridge respirators.

Abstract

This article is the third in a series of four articles on respirator history. This article continues to follow the history of respirator approval, use, and improvements in the US as discussed in our article entitled, History of U.S. Respirator Approval, published in the ISRP Journal, Vol. 35, No. 1, 2018 (Spelce. et. al.2018). In addition, a 1957 respirator decision logic diagram illustrates the U.S. Bureau of Mines (USBM) rules to follow for respirator selection (USBM 1957).