Atmosphere-supplying respirator

The only situation when ambient blanks may provide remotely meaningful results is the sampling for analyses with extremely low detection limits in atmospheres so heavily contaminated that respirators or supplied air are mandated for field personnel. These types of sites, however, are usually grossly contaminated with hazardous waste, and possible ambient contamination is not a matter of concern. 

For a concise discussion of both air-purifying and atmosphere-supplying respirators, see N. I. Sax and R. J. Lewis, Sr., Hazardous Chemicals Desk Reference, Van Nostrand Reinhold, New York, 1987, pp. 22-42. 

The level of protection that can be provided by a respirator is indicated by the respirator s protection factor (PF). This number, determined experimentally by measuring facepiece seal and exhalation valve leakage, indicates the relative difference in concentration of the concentrations of substances outside and inside the facepiece that can be maintained by the respirator. For example, a PF of 10 for a respirator means that a user could expect to inhale no more than one tenth of the airborne contaminant present. A source of protection factors for various types of atmosphere-supplying and air-purifying respirators can be found in the American National Standards Institute (ANSI) standard ANSI Z-88.2-1980. 

Atmosphere-supplying respirator means a respirator that supplies the respirator user with breathing air from a source independent of the ambient atmosphere, and includes supplied-air respirators (SARs) and self-contained breathing apparatus (SCBA) units. 

Self-contained breathing apparatus (SCBA) means an atmosphere-supplying respirator for which the breathing air source is designed to be carried by the user. 

Altitude(ft.) Oxygen deficient atmospheres (% O2) for which the anployer may rely on atmosphere supplying respirators... 

The employershall ensure that compressed oxygen is not used in atmosphere-supplying respirators that have previously used compressed air. 

An atmosphere-supplying respirator that provides a continnons flow of breathable air to the respirator facepiece. 

An atmosphere-supplying respirator that admits breathing air to the facepiece only when a negative pressure is created inside the facepiece by inhalation. 

Atmosphere supplying respirator— Any respirator that provides clean air from an uncontaminated source to the face piece examples include supplied-air (airline) respirators, self-contained breathing apparatus (SCBA), and combination supplied air/SCBA devices. 

Respiratory protection — If the right type of respirator is not being used, employees are not being adequately protected. In most cases, the standard requires that atmosphere-supplying respirators be used. An atmosphere-suppl3dng respirator provides your employee with a steady source of clean air. Respirator use must follow requirements in OSHA s standard on respiratory protection. 

Procedures to ensure adequate air quality, quantity, and flow of breathing air for atmosphere-supplying respirators... 

The category of respirator, i.e., air-purifying or atmosphere-supplying style, whether half or full-face and type of filter or canister all must be carefully selected. En loyees must be properly fitted for PPE and trained in when and how to use it. A medical evaluation of a person s ability to effectively wear and use a respirator must also be conducted. 

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