Respiratory protection might be necessary when working with highly toxic chemicals, biological hazards, or dusts known to cause asthma or pulmonary fibrosis. However, respirators are a “last line” of defense, and should not be used until all engineering controls (e.g. ventilation) and work practice controls (e.g. product substitution) are exhausted. Respirators have specific regulatory requirements for equipment certification, fit testing, medical evaluation, and training. These requirements are from the OSHA Respiratory Protection Standard 29 CFR 1910.134. Requirements differ based on respirator type.

The respirator regulations do not cover “comfort masks” or surgical masks (Figure 5.5). These are technically not respirators, as they are not certified by NIOSH (the National Institute for Occupational Safety and Health), and have no protection factor rating. If you are using these masks in the lab, consider whether you might need a true respirator such as those depicted in Figure 5.6.

Because of the training, fit testing, and medical evaluation requirements, you cannot “casually” wear true respirators in the lab. If you wish to wear an N95 disposable respirator, you must receive training on its proper use and limitations. This training is available online.

Other types of respirators such as APRs, PAPRs, SARs, and SCBAs have more rigorous training and fit testing requirements. Contact EHS if you are contemplating their use. If you will use any type of respirators voluntarily, including N95 disposable respirators, you must read and understand the information included in Appendix 5-A at the end of this chapter.