All toolsSafe Exposure Time Calculator

Level and time share the same budget.

Move the slider to see how a constant A-weighted level changes the NIOSH daily occupational exposure estimate.

NIOSH exposure estimate

How does level change the daily estimate?

NIOSH uses an occupational reference of 85 dBA for 8 hours. Each 3 dB increase halves the estimated duration.

Educational occupational estimate only. It is not an individual guarantee of safety and does not account for every sound or exposure pattern.

Selected sound level94 dBA
Estimated time to 100% NIOSH daily occupational dose1 hour

Model: 85 dBA = 8 hours, with a 3 dB exchange rate. Assumes a constant level.

How it works

The 3 dB exchange rate

The model starts at 85 dBA for 8 hours. Every 3 dB increase doubles sound energy and halves the estimated duration: 88 dBA for 4 hours, 91 dBA for 2 hours and 94 dBA for 1 hour.

Important limits

An occupational estimate, not a promise

NIOSH REL is designed for workplace exposure. Individual susceptibility varies, and impulse sounds, changing levels and non-work listening need more context than this single-level estimate provides.

Measurement context

Your input matters

Phone measurements depend on the microphone, processing and calibration. dBcheck is not a certified Class 1 or Class 2 instrument, so do not use an unverified reading for regulatory decisions.