Safe Exposure Times by Decibel Level
NIOSH recommends a limit of 85 dBA averaged over an 8-hour day. For each 3 dB above that, the safe time is cut in half:
- 85 dBA: 8 hours
- 88 dBA: 4 hours
- 91 dBA: 2 hours
- 94 dBA: 1 hour
- 97 dBA: 30 minutes
- 100 dBA: 15 minutes
The rule also runs the other way, so 82 dBA is safe for 16 hours. The times cover a whole day: an hour of loud traffic and an hour of loud music add up.
To check a level as it happens, the decibel meter shows the reading live. The concert decibel meter and the workplace noise meter also show how long is safe at that level.
NIOSH, OSHA, and WHO Limits Compared
Three limits are quoted most often. They differ because they answer different questions.
- NIOSH: 85 dBA for 8 hours, halving every 3 dB. It is a recommendation, and stricter than the OSHA rule.
- OSHA: 90 dBA for 8 hours, halving every 5 dB, so 95 dBA for 4 hours and 100 dBA for 2 hours. This is the legal limit for US general industry. Continuous noise may never go above 115 dBA, and impact noise should stay under a 140 dB peak.
- WHO: 80 dB for up to 40 hours a week, for music and other listening outside work. At 90 dB the safe time drops to 4 hours a week.
OSHA also sets an action level of 85 dBA averaged over 8 hours. Above it, the employer must run a hearing conservation program, with noise monitoring and hearing tests. The WHO times are per week, not per day.
How Loud Everyday Sounds Are
WHO lists these typical levels, with the most time per week you can safely hear each one:
- Normal conversation, 60 dB: no limit
- Doorbell, 80 dB: 40 hours
- Heavy traffic, heard inside a car, 85 dB: 12 hours 30 minutes
- Shouted conversation, 90 dB: 4 hours
- Motorcycle, 95 dB: 1 hour 15 minutes
- Hair dryer, 100 dB: 20 minutes
- Car horn at 5 meters, 105 dB: 8 minutes
- Standing near a siren, 120 dB: 12 seconds
For more sounds and their daily limits, see the noise levels chart.
Signs a Sound Is Too Loud
The CDC gives a quick test. If you have to talk extra loud to someone a few feet away, the noise is probably hurting your hearing.
Loud sound tires the sensory cells in the inner ear. WHO says the result can be temporary hearing loss or ringing in the ears (tinnitus), and regular exposure can make both permanent. Hearing lost to noise does not come back.
The CDC says you can lose some hearing after about an hour on a motorcycle, or in under half an hour at a sports game. Headphones at full volume can do it in a few minutes, and a nearby siren in less than a minute.
How to Protect Your Hearing
- Keep headphones at no more than 60% of their maximum volume, as WHO advises.
- Wear earplugs or ear defenders at concerts, sports games, and with loud tools. Our concert earplugs guide compares hi-fi earplugs for music, and you can compare earplugs made for musicians by filter and NRR.
- Stand away from loudspeakers. The farther you are, the lower the level.
- Give your ears a break: WHO suggests 10 minutes in a quiet space after every hour somewhere loud.
- Measure instead of guessing. A phone reading is an estimate, so see how accurate a phone decibel meter is and how to calibrate it.