Using a personal fall arrest system is no different than using any other personal protective equipment. In the hierarchy of protection, it is the last resort. The first step should be to remove fall hazards through engineering controls, such as guardrails.
The Occupational Safety and Health Administration (OSHA) estimates that 5 million U.S. workers are required to wear respirators. For linemen and wiremen, respirators protect against environments with insufficient oxygen levels, harmful airborne dusts, fogs, smokes, mists, gases, vapors and sprays.