Document 5yzwNDKaxwam91JBaxQzKEK5

22696 Federal Register / Vol. 51, No. 119 / Friday, June 20, 1906 / Rules and Regulations protection factors less than 10. That is, afforded by different respirator types: While the employer must select the the fit test procedures are designed to The current classification system (30 appropriate respirator from the table on. reject respirators that have protection CFR Part 11) has been in place for many the basis of the airborne concentration factors less than 10, so these should not years and has provided a degree of of asbestos, he may always select a be worn by the worker (47 FR 51110- quality assurance that cannot be respirator providing greater protection, 51119). However, when applying disregarded in light of the existing that is, one prescribed for higher statistical computations of a one-sided limited data. Finally, OSHA believes concentrations of asbestos than present upper confidence limit for the true that no respirator reliably achieves the in his workplace. percentage of wearers who will assigned protection factor in practical, Recently published field studies as experience protection factors less than routine use, and therefore, respirators well as environmental chamber studies 10, the results are that many workers do are inferior to engineering and work conducted by the Los Alamos National t.-.. not achieve the acceptable protection. practice controls. At best, the protection Laboratory indicated that the tight For example, for the dust, fume and mist factors obtained in the studies show fitting powered air-purifying respirators filters, tested after passing the saccharin only relative differences between (PAPRs) offer more protection that the fit test, and while weuring the respirator respirators (that is, some may be better loose fitting PAPRs. Since the affected for protection against asbestos under than others), but do not show that any employees are seldom exposed to more use, exposure, and wearer conditions respirator provides consistently reliable than 100 times the permissible exposure similar to those existing in the study, protection. OSHA feels that further field limit for asbestos, a single classification one can state with 99% confidence thut testing of respirators should continue, so which covers all the PAPRs and up to 10% (about 1 in 6) of the users may as to provide more definitive continuous flow supplied-air respirators experience protection factors less than information regarding the adequacy of is used for simplification of the 10. Finally, but equally importantly. those negative pressure air-purifying respirator selection table. OSHA does not believe that the respirators not equipped with high The above explanation on respirator conditions in the study represent the efficiency filters. Therefore, OSHA selection provides the rationale for typical respirator program found in use. continues to believe that the respirator OSHA's deletion of the section on even in the best situations, because the selection process should be based on "spraying, demolition, or removal" study created a carefully controlled the performance of the entire class of which appears in the current standard. environment of respirator use. In spite of respirators and not based on the This eliminates any ambiguity which the typical and excellent respirator performance capabilities of selected existed previously regarding the kind of program in place during the study, respirators within a given class. In the respirator required to protect employees adequate respirator protection was not final standard OSHA limits the selection engaged in spraying, demolition and obtained from many respirator types. of negative pressure half-mask removal operations. Furthermore, the This fact, and the unexplained respirators to high efficiency filters only. final standard is consistent with current inconsistency in the data, further Because of the unreliability and enforcement policy. support OSHA belief.that respirators should not be relied upon to provide primary protection to workers. physiological distress associated with negative pressure respirators, OSHA has required employers to provide The standard further requires that the employer institute a respiratory protection program in accordance with OSHA recognizes, however, that powered, air purifying (positive paragraph (g)(3). This section contains where engineering and work practice pressure) respirators (PAPR) to basic requirements for proper selection, controls cannot reduce exposure below employees who request one, so long as it use, cleaning and maintenance of the PEL, respirators must be used. This will provide adequate protection at the respirators. The standard also requires study suggests that respirators will level of protection required. Powered that respirators be properly cleaned and provide some measure of protection, but air-purifying respirators operated in filters replaced when necessary. uncertainties in the study do not allow it positive-pressure mode provide greater The employer is also required to to be used to define respiratory protection to individuals, especially assure that the respirator assigned will efficiency. those who cannot obtain a good face fit fit properly. Proper fit of the respirator is The NIOSH/MSHA respirator on a negative pressure respirator, and critical. As a negative pressure is certification procedures, described in 30 will provide greater comfort when a created within the facepiece when the CFR Part'll, establish classes of respirator needs to be worn for long wearer breathes, unfiltered respirators. Each class is defined by a - periods of time. OSHA believes . contaminated air may enter the set of criteria for the capabilities of the employees will have a greater incentive facepiece if gaps exist. Obtaining a respirator class. OSHA notes that the to wear respirators if discomfort is proper fit'on each employee may require testing of respirator effectiveness for minimized. the employer to provide two or three asbestos (the LASL and DuPont studies) The standard requires the employer to different mask styles. In order to help suggest that certain respirators within a select respirators in accordance with assure that respirators will provide - "class "appear toTterform better'Than Table 1 (in the regulatory text) from employees with the necessary other respirators within the same class. those jointly approved by NIOSH/ protection, the standard requires For example, the 3M 8710 respirator MSHA. The respirator selection table employers to periodically perform either appears to provide better protection wilt enable the employer to provide the qualitative (QLFT) or quantitative than the other respirators in its class as type of respirator whjch affords the (QNFT) fit tests on all users of half- a.single-use respirator. OSHA does not proper degree of protection based on the mask negative pressure respirators. believe that it is appropriate to make airborne concentration of asbestos. To Although the Agency, feels that QNFT is. exceptions for certain respirators within comply with this requirement the more accurate than QLFT, it is OSHA's a class.of NIOSH/MSHA certified employer must perform initial opinion the QLFT can provide the same respirators at this time. As noted above, monitoring.as described in paragraph assurance of employee health protection . the existing data is not comprehensive (d)(2) to accurately determine the as QNFT in instances where protection and some is inconsistent with the airborne concentration of asbestos to factors up to 10 are required, and when current knowledge of protection which employees may be exposed. specific protocols are followed for hslf- GLEASON-000944