Cadmium

OSHA's proposed generalizations, if not paired with clear equivalency guidance, risk shifting complex respirator selection and cartridge change out decisions to employers without adequate direction - particularly for immediately dangerous to life or health (IDLH) atmospheres and agent specific constraints (e.g., ethylene oxide sorbent limitations, methylene dianiline [MDA], or formaldehyde STEL scenarios). OSHA should retain non-exhaustive examples of acceptable respirator configurations mapped to exposure tiers (action level, PEL, STEL, IDLH) and common tasks, while referencing §1910.134 for program elements; an appendix crosswalk should state that following the mapped equivalents constitutes compliance. . OSHA's rationale that all NIOSH approved filters under 42 CFR Part 84 are "efficient in preventing the penetration of submicron sized particles" overlooks material differences in allowable penetration. AIHA opposes deletion of explicit HEPA (or N100/P100) requirements in these standards. Given toxicity and carcinogenicity profiles, sub-micrometer particles and short, thin asbestos fibers penetrate N95 media more readily than P100/HEPA. Simulated workplace studies show P100 outperforms N95 for 10–400 nm aerosols; a precautionary, ALARA-consistent approach warrants retaining N100/P100 (or HEPA) as the minimum for these agents. By definition, N95 filters may permit up to 5% particle penetration, whereas N100/HEPA filters permit up to approximately 0.03% penetration (99.97% efficiency). For carcinogenic metal fumes (Pb, Cd, As) and aerodynamically submicron asbestos fibers, this difference - on the order of a 167 fold margin - matters. In practice, higher efficiency filters provide necessary safety buffers for real world conditions that deviate from laboratory assumptions (e.g., face seal variability, high work rates, elevated particle loading). Accordingly, OSHA should maintain explicit requirements for HEPA or N100/P100 filters in these substance specific standards rather than defaulting to the broad "any NIOSH approved filter" formulation. Where OSHA wishes to streamline language, the Agency can reference 29 CFR 1910.134 but preserve a normative statement that, for the substances listed above, the minimum filter efficiency shall be N100/HEPA (P100 where oil aerosols may be present). AIHA also opposes removing the "PAPR upon request" provisions. Comfort and lower breathing resistance drive adherence; some workers require higher protection factors or loose-fitting PAPRs (e.g., for fit limitations or facial hair). Eliminating this option would reduce real-world compliance and protection. Please see addtional comments in the attached file.