Respirator Performance against Nanoparticles under Simulated Workplace Activities.

Area of Science:

• Occupational Health and Safety
• Respiratory Protection
• Nanotoxicology

Background:

• Filtering facepiece respirators (FFRs) and elastomeric half-mask respirators (EHRs) are crucial for worker protection against hazardous particles, including engineered nanoparticles.
• Evaluating respirator performance under realistic conditions is essential for ensuring worker safety in diverse industrial environments.

Purpose of the Study:

• To assess the performance of FFRs and EHRs against particles ranging from 10-400 nm under simulated workplace conditions.
• To compare the effectiveness of N95 and P100 rated respirators across different particle sizes and respirator types.

Main Methods:

• Twenty-five healthy subjects performed six standardized exercises simulating workplace activities while wearing N95/P100 FFRs and EHRs.
• Simulated workplace protection factors (SWPFs) were measured using scanning mobility particle sizers to determine upstream and downstream particle concentrations.
• Quantitative fit testing was conducted prior to SWPF testing to ensure proper respirator seal.

Main Results:

• P100 EHRs demonstrated the highest geometric mean SWPF, followed by P100 FFRs, N95 EHRs, and N95 FFRs across all particle size ranges (10-400 nm).
• All tested respirators performed equally or better with smaller nanoparticles (10-100 nm) compared to larger particles (100-400 nm).
• P100 respirators showed significantly higher SWPFs than N95 respirators for both FFR and EHR types (P < 0.05).

Conclusions:

• Class P100 respirators provide superior protection compared to N95 respirators for both FFR and EHR types under simulated workplace conditions.
• All evaluated respirator types met or exceeded the expected performance standard (fifth percentile SWPF > 10) for the tested particle sizes.
• The findings support the use of P100 rated respirators for enhanced protection against a wide range of airborne particles, including nanoparticles.