Editing Respirator (section)

=== Under 30 CFR 11 ===
{{further|30 CFR 11}}
In 1992, NIOSH published a draft report on the effectiveness of respirator regulations under the then-current [[30 CFR 11]]. Particulate respirators back then were mainly classified as either [[DM respirator|DM, DFM, or HEPA]].<ref>{{harvnb|NIOSH|1992}}</ref>

==== Respirator risk modelling ====
[[Respirator assigned protection factors|Assigned protection factors]] (APF) are predicated on the assumption that users are trained in the use of their respirators, and that ''100%'' of users exceed the APF.<ref>"NIOSH has concluded that APFS based on APF definitions from Myers et al. and the Guy Committee are derived from WPF data that were obtained after each test subject has been properly fitted and trained"... {{harvnb|NIOSH|1992|p=34}}</ref> This "simulated workplace protection factor" (SWPF) was said to be problematic:
{{blockquote|By inference, these data are equally at odds with the protection factors established by OSHA for various types of respirator, which were based on QNFT [quantitative fit testing] data obtained by the [[Los Alamos National Laboratory]] in the 1970s. Until recently, the SWPFs gathered during QNFT were more or less assumed to translate directly into the protection afforded by a particular respirator, or class of respirators, while worn in the workplace.{{break}}{{break}}
Apparently this is now a questionable assumption which has thrown the entire concept of fit testing into doubt.<ref name="openforum">Quote from: {{citation| title=Open Forum: Respirator Testing-Old Values |date= May 1989 |publisher=Ind. Safety and Hyg. News}}</ref>}}
The ideal assumption of ''all'' respirator users exceeding the APF is termed the ''zero control failure rate'' by NIOSH. The term ''control failure rate'' here refers to the number of respirator users, per 100 users, that fail to reach the APF.<ref name="NIOSHp52">{{harvnb|NIOSH|1992|p=52}}</ref> The risk of user error affecting the ''failure rate'', and the studies quantifying it, was, according to NIOSH, akin to the study of [[Comparison of birth control methods|contraception failure rates]].<ref>{{harvnb|NIOSH|1992|p=51}}</ref> 

This is despite there being a "reasonable expectation, of both purchasers and users, [that] ''none'' of the users will receive less protection than the class APF (when the masks are properly selected, fit tested by the employer, and properly worn by the users)". NIOSH expands on the methods for measuring this error in Chapter 7 of the draft report.<ref name="NIOSHp52" />

==== Qualitative fit testing ====
Qualitative fit testing with isoamyl acetate, irritant smoke, and saccharin were proposed as alternatives to quantitative fit testing in the 1980s, but doubts were raised as to its efficacy.<ref name="page35">{{harvnb|NIOSH|1992|pp=35-36}}</ref> 

With regards to the effectiveness of fit testing in general, others have said:<ref name="page35" /> {{blockquote|First of all, it is unfortunate that fit testing results apparently cannot be used as a reliable indication of respirator performance in the workplace. Life would be simpler if the converse were to continue to be true...{{break}}{{break}}
In my opinion, we are left with respirator fit testing, whether qualitative or quantitative, playing the role as a means of obtaining the best possible fit of a given respirator on a given person at a given time. We should not make any representation as to the ultimate efficiency in the workplace.<ref name="openforum" />}}

==== Exercise protocols ====
With regards to fit test ''protocols'', it was noted by NIOSH that "time pressures" resulted in the exclusion of intense exercises meant to simulate workplace use:<ref name="page37">{{harvnb|NIOSH|1992|p=37}}</ref> {{blockquote|Part of the original test procedure called for test subjects to be stressed by treadmill, while undergoing a quantitative respirator leak evaluation. The purpose of this stressing was to simulate actual workplace use of the respirators. We accordingly abandoned the "stress" portion of the exercises, and substituted a period to be spent in a hot humid chamber, to work up a sweat, as a substitute for physical activity.<ref>{{citation |last=Douglas |first=D. D. |title=Respirator Studies for the National Institute for Occupational Safety and Health, July 1, 1974-June 30, 1975, Los Alamos Scientific Laboratory Progress Report LA-6386-PR |publisher=Office of Scientific and Technical Information|location=Los Alamos, New Mexico |pages=35–36 |date=August 1976}}</ref>}}
Neither exercise was included in the [[OSHA]] fit test protocols. Put another way, it has been said:<ref name="page37"/> {{blockquote|The exercise time limits are very short. The required exercises are sedentary and do not replicate movements of workers that may occur in workplaces.<ref>{{citation |first=W. H. |last=Revoir |title=Comments on OSHA's Proposal to Modify Existing Provisions for Controlling Employee Exposure to Toxic Substances Found in 29 CFR 1910.1000(3) and 29 CFR 1910.134(a)(1). Comments submitted to OSHA |date=1990-05-30 |page=20}}</ref>}}

==== Noncompliance with regulation ====
In spite of the requirement to fit test by OSHA, the following observations of noncompliance with respirator regulations were made by NIOSH and OSHA:<ref name="page45">{{harvnb|NIOSH|1992|p=45-46}}</ref>
* Almost 80% of negative-pressure respirator wearers were not receiving fit testing.
* Over 70% of 123,000 manufacturing plants did not perform exposure-level monitoring, when selecting respirators to use in the plants.
* Noncompliance increased to almost 90% for the smallest plants.
* 75% of manufacturing plants did not have a written program.
* 56% of manufacturing plants did not have a professional respirator-program administrator (i.e., qualified individual supervising the program).
* Almost 50% of wearers in manufacturing plants did not receive an annual examination by a physician.
* Almost 50% of wearers in manufacturing plants did not receive respirator-use training.
* 80% of wearers in manufacturing plants did not have access to more than one facial-size mask, even though nearly all reusable masks were available in at least three sizes.<ref name="page45" />
These noncompliance errors make up what NIOSH calls the ''program protection factor'':<ref name="page47">{{harvnb|NIOSH|1992|p=47}}</ref>{{blockquote|...NIOSH has concluded that all respirator workplace studies reported in the 1980s and early 1990s are ''respirator-performance'' studies, not ''respirator program evaluation studies''. That is, they evaluate ''workplace protection factors'', not ''program protection factors''.

WPF studies frequently are conducted primarily to demonstrate "adequate protection" from a particular make and model respirator. Thus, in effect, WPF studies generally are designed and conducted to measure only respirator performance in the most favorable light possible. This is done to avoid reducing or "biasing" (i.e., systematically distorting) the observed respirator protection resulting from poorly-performed or inadequately-performed respirator program elements that are typically found in actual programs. A major objective in respirator-performance (WPF) studies is to minimize the effects of human errors, even though these errors may typically occur in actual workplace use of respirators...<ref name="page47" />
}}

==== Adherence to the regulatory minimum ====
[[File:Part 11 respirator final air-purifying APFs (1992) - illustration - page 137.jpg|alt=Table of final APFs for Part 11|thumb|Final Part 11 APFs proposed by NIOSH for air-purifying respirators, with DM respirator APFs lowered to 2.]]
APFs may be based on the filtration performance from one or two manufacturers that barely pass the regulation. When the DM and DFM respirator filter standards at the time were found to have an unacceptably high filter leakage, NIOSH proposed lowering the APF for DM respirators from 10 to 2. On this scale, 1 is a completely ineffective respirator. Some respirator manufacturers, like [[3M]], complained that DM and DFM respirators with superior filtration, that would normally receive an APF well above 2, were being "held hostage" by poorly-performing respirators.<ref>{{harvnb|NIOSH|1992|p=127}}</ref> While NIOSH acknowledged the predicament poorly-performing respirators were having on superior respirators in the same class, they concluded that the APFs, for respirator classes like DFM halfmask respirators, should be lowered to at least 6, despite APFs of 6 through 10 being allowed previously for DFM halfmasks.<ref>{{harvnb|NIOSH|1992|p=128}}</ref>

[[ANSI]] suggested additional contaminant monitoring by employers to allow for the use of DM and DFM respirators, when the [[Median aerodynamic diameter|mass median aerodynamic diameter]] of dusts in contaminated workplaces is such that DM and DFM respirators ''could work''. However, NIOSH pointed out that the poor adherence to OSHA regulations on exposure-level monitoring by employers, as well as lack of expertise in interpreting the collected data, would likely result in more workers being put at risk.<ref>{{harvnb|NIOSH|1992|pp=132-133}}</ref> In addition, NIOSH pointed out that the ANSI recommendations would effectively mandate the use of ''expensive'' Part 11 HEPA filters under Part 11 regulations,<ref>{{harvnb|NIOSH|1992|p=135}}</ref> due to lack of adherence to exposure-level monitoring rules.<ref>{{harvnb|NIOSH|1992|p=136}}</ref>