The respirator is historically one of the oldest types of equipment used for personal protection in the occupational setting. It is uncertain when the use of primitive forms of respiratory protection began. However, Pliny the Elder recorded the first known use of such a device early in the 1
st
century
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. Although respirators have been used for almost 2000 years, the genesis of their technical development is actually the mid‐19th century. During that century. Despite major advances in knowledge and technology, respirator development continued slowly. Chemical warfare agents, introduced in World War I, focused attention on the need for adequate respirators. In the United States, the Bureau of Mines successfully carried out this work for the army. The forerunners of present‐day respirators began to appear after World War I. In those early years, misuse of surplus army gas masks by civilians and employers, who had sole discretion about deciding when and how respirators were used, highlighted the need for respiratory protection standards.
The Bureau of Mines in 1919 initiated the first respirator certification program in the United States and certified their first respirator, a self‐contained breathing apparatus in 1920. Responsibility for the respirator certification program was transferred from the Bureau of Mines to NIOSH in 1972. In 1995, NIOSH promulgated new certification regulations, Title 42
Code of Federal Regulations
Part 84 (Part 84). Knowing the minimum performance standards and recognizing the limitations of the NIOSH certification tests are important when selecting and using a “NIOSH‐certified” repirator. Achieving proper respiratory protection with NIOSH‐certified RPE requires that (
1
) the RPE be properly selected for the environment in which it will be used; (
2
) its face fitting characteristics be adequately evaluated and considered in the selection process; and (
3
) workers receive periodic training that adequately prepares them to conscientiously and properly wear and use the RPE.
Three recognized standard‐producing groups have produced guidance or standards on establishing and maintaining the elements of a good respiratory protection program. They are:
The American National Standards Institute (ANSI),
The National Institute for Occupational Safety and Health (NIOSH), and
The Occupational Safety and Health Administration (OSHA).
The primary objective of industrial hygiene is to prevent contaminants from escaping into the atmosphere. Hazard control should start at the outset of process, equipment, and plant design stages so those potential exposure sources can be engineered out. But very often exposure control becomes an issue after the process(es) are operational and therefore control becomes a more difficult and costly proposition. However, even then consideration should be given to the use of effective engineering controls to eliminate and/or reduce exposure to respiratory hazards. The preferred priority of controls steps are (
1
) substitution of a less toxic substance, (
2
) encapsulation or isolation of the process, (
3
) use of local exhaust ventilation or general ventilation in conjunction with filters and scrubbers to control the effluents, (
4
) use of personal protective equipment (PPE).
Respiratory protective equipment should be used only when all higher priority control steps are not technically or financially feasible. Real world circumstances however demonstrate that engineering controls often do not reduce exposures sufficiently to eliminate a respiratory hazard. As a result respiratory protective equipment (RPE) becomes the only technically and economically feasible adjunct to engineering controls to minimize and control respiratory exposures. According to recent estimates reported by the OSHA Office of Regulatory Analysis, roughly 5 million workers, 19–20% of the mining/manufacturing/ construction workforce, in 1.3 million establishments use or have access to some type of respiratory protective equipment. Thus, RPE continues to be an important component in many respiratory exposure control plans. As a result, selection, use and evaluation of RPE have become more important as well.
