AEGIS-SW-2026-0803-001 · Rev H
Live sound level, exposure dose, and 85 dBA alerting. Accumulates only while this screen is open and in front.
Apple values are from the AirPods Pro 2 Hearing Protection Data Sheet, Rev A October 2024. Active figures are Noise Reduction Statistic (NRSA) per ANSI S12.68-2007, level-dependent and interpolated between Apple's published points; the pair is the 80th and 20th percentile of user fit. Passive NRR is 10 dB per 40 CFR Part 211 Subpart B, measured to ANSI S3.19-1974, and applies only with the feature off. Pro 3 uses Pro 2 figures, which is conservative — independent lab measurement puts Pro 3 roughly 10 dB better. Apple states the feature is U.S. and Canada only.
Conventional protector attenuation uses the OSHA 1910.95 Appendix B method for A-weighted measurements with the recommended 50% field derate: effective dB = (NRR − 7) ÷ 2. That halving accounts for the gap between laboratory fit and real-world fit. Dose, TWA, and alerts all run on the at-the-ear number once a rated device is selected.
| Level | OSHA (5 dB) | NIOSH (3 dB) |
|---|
OSHA 29 CFR 1910.95 uses a 5 dB exchange rate with a 90 dBA PEL and 85 dBA action level. NIOSH recommends 85 dBA on a 3 dB exchange rate, which is why its permitted times are far shorter at the same level. AEGIS policy sets mandatory hearing protection at 85 dBA — stricter than the OSHA requirement, matching the NIOSH REL. No exposure above 115 dBA unprotected, and none above 140 dB peak for impulsive noise.