Hearing safety
Safe noise levels and exposure times
How loud is too loud, and for how long? Here is what NIOSH and the WHO recommend, in plain English, with a quick exposure-time table.
The NIOSH guideline: 85 dBA for 8 hours
The US National Institute for Occupational Safety and Health (NIOSH) sets a recommended exposure limit (REL) of 85 dBA as an 8-hour time-weighted average, using a 3 dB exchange rate: every 3 dB increase halves the recommended time. Some legal workplace limits (for example the US OSHA limit of 90 dBA with a 5 dB exchange rate) are less protective than the NIOSH recommendation.
| dBA | Max time per day (NIOSH REL) | Zone |
|---|---|---|
| 85 | 8 hours | Risky over time |
| 88 | 4 hours | Risky over time |
| 91 | 2 hours | Risky over time |
| 94 | 1 hour | Risky over time |
| 97 | 30 minutes | Risky over time |
| 100 | 15 minutes | Harmful quickly |
| 103 | 7.5 minutes | Harmful quickly |
| 106 | about 4 minutes | Harmful quickly |
| 109 | about 2 minutes | Harmful quickly |
| 112 | about 1 minute | Harmful quickly |
| 115 | about 30 seconds | Harmful quickly |
WHO safe-listening guidance
The World Health Organization (with the ITU) frames safe listening as a weekly sound allowance — roughly equivalent to 80 dBA for 40 hours a week for adults, with a lower allowance suggested for children. Its standard for venues and events recommends keeping average levels to about 100 dBA over any 15 minutes, with quiet zones and hearing protection available. Louder means less time: the allowance runs out much faster at concert levels.
What the zones on our meter mean
Everyday quiet to normal speech.
Noticeably loud. Fine for a while; long days add up.
NIOSH’s 85 dBA / 8 h limit starts here. Time limits shrink fast.
Minutes, not hours. Use hearing protection.
Can hurt and damage hearing in moments.
Practical ways to protect your hearing
- Turn it down: cutting just 3 dB doubles your recommended time.
- Step back: doubling your distance from a loud source lowers the level by about 6 dB.
- Take breaks: give your ears quiet time after loud events.
- Use protection: well-fitted foam earplugs or earmuffs cut noise substantially; musician earplugs keep sound clearer.
- Watch headphones: many phones offer a headphone-level warning or volume limit — use it.
Check a space with the free decibel meter, compare levels in how loud is 80 or 100 dB, and read the phone accuracy tips before trusting a single number.
Frequently asked questions
What is a safe decibel level?
As a general guide, levels below about 70 dB are considered comfortable for everyday life. NIOSH recommends limiting exposure to 85 dBA averaged over 8 hours, with the allowed time halving for every 3 dB above that.
How long can I listen at 100 dB?
Under the NIOSH guideline, about 15 minutes a day at 100 dBA. At 103 dBA it is about 7.5 minutes, and at 106 dBA about 4 minutes.
Is 85 dB harmful?
85 dBA is the NIOSH threshold for an 8-hour day. Short periods are not usually a concern, but regular long exposure at or above this level raises the risk of noise-induced hearing loss.
What is the 3 dB exchange rate?
It means every 3 dB increase in level doubles the sound energy, so the recommended exposure time is cut in half. For example 85 dBA for 8 hours, 88 dBA for 4 hours, 91 dBA for 2 hours.
Can a phone tell me if noise is safe?
A phone or browser meter can give a useful rough idea, but it is not a certified, calibrated sound level meter or noise dosimeter. For workplace compliance or medical concerns, use certified equipment or ask a professional.