Editing Respirator (section)

==== 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>