A-weighted level. If measuring now, use the meter's average over 30–60 s.
Leave blank to see only the maximum. Enter how long you were at this level.
How the Calculation Works
Every increase of 3 dB doubles sound energy, so NIOSH halves the recommended time:
Example: 88 dBA → 8 × 2(85−88)/3 = 8 × 2−1 = 4 hours. 94 dBA → 1 hour. 100 dBA → ~15 minutes.
If you also enter how long you were exposed, the tool estimates % of daily dose:
dose = 100 × (yourMinutes / maxMinutes). Above 100% means you have exceeded the NIOSH recommended limit
for that day. Treat all results as reference only — real risk also depends on frequency content, impulse character,
and individual susceptibility.
Examples
- 85 dBA for 60 min → max 480 min → ~12% of daily dose (low).
- 94 dBA for 45 min → max ~60 min → ~75% of daily dose (moderate — limit further exposure).
- 100 dBA for 30 min → max ~15 min → ~200% of daily dose (high — reduce time or protect).
Measure with the online decibel meter using A-weighting and the average/Leq over the full period you care about — not a single instant.
Limits & Disclaimer
- Based on NIOSH REL (85 dBA, 3 dB exchange). OSHA and other authorities differ — this page does not combine them.
- Browser/phone levels are estimates — they are not substitutes for a calibrated IEC 61672 meter. See Accuracy.
- This is educational information, not medical or legal advice. For hearing concerns consult a professional; for workplace compliance follow your national regulations and a qualified hygienist.
References: NIOSH/CDC noise and hearing loss prevention (cdc.gov/niosh/noise), WHO hearing topics (who.int), OSHA noise (osha.gov/noise).