Abstract
Federal regulations recognize the need to determine whether individuals are physically able to perform their job while wearing respirators. A variety of safety and workplace factors should also be considered at the time that a respiratory protective device is evaluated for use by a particular worker. In most negative pressure respirators, inspiratory resistance constitutes the major load on the respiratory system. In normals, the major load to the cardiovascular system occurs with heavy, self-contained respirators. In the absence of objective guidelines for the use of respirators by impaired workers, careful examination and conservative clinical judgement, and the willingness to re-assess choices must form the basis of respirator selection.