Wear hearing protection when sound reaches 85 dBA and you’ll be in it for a while, and any time you’re near impulse noise like gunfire or fireworks. NIOSH puts it plainly: repeated exposures to sounds that are 85 dBA or higher can cause permanent hearing loss.
Above 85, the question becomes how long. NIOSH’s recommended exposure limit allows 8 hours a day at 85 dBA and halves the allowance for every 3 dB more, so 94 dBA is an hour and 100 dBA is fifteen minutes.
How to tell you’re near 85 dB without a meter #
NIOSH gives two rules of thumb. Sounds around 85 dBA often require you to raise your voice to be heard by someone three feet away. At 95 dBA or higher, you likely have to shout to be heard at that distance.
Other signals that you’ve been somewhere too loud: ringing or buzzing afterward, muffled hearing, or a feeling of fullness in the ears. Those usually fade, but they mean the exposure was too much. If they don’t fade within a day or two, or they keep coming back, see a doctor or an audiologist. Signs of noise-induced hearing loss covers what to watch for.
Activities where protection is worth it #
| Activity | Typical level | Protection |
|---|---|---|
| Vacuuming, busy restaurant | 70 to 80 dBA | Not needed for hearing |
| Gas lawn mower, leaf blower | around 90 dBA | Yes, for the whole job |
| Circular saw, router, angle grinder | 95 to 105 dBA | Yes, every time |
| Nightclub, bar with live music | 95 to 105 dBA | Yes, filtered plugs work well |
| Rock concert | 100 to 110 dBA | Yes |
| Chainsaw, jackhammer | around 110 dBA | Yes, consider plugs plus muffs |
| Motorsport event, air show | 100 dBA and up | Yes, muffs for children |
| Firearms, fireworks at close range | 140 dB peak and up | Always, no exceptions |
NIOSH’s own examples of 85 to 90 dBA equipment include printing presses, lawn mowers, vacuums and power tools. At 95 dBA and above it lists bulldozers, ambulance sirens, chain saws, bars and nightclubs, and large sporting events.
Impulse noise is the category people underestimate. A single unprotected gunshot can injure hearing immediately. OSHA’s rule for workplaces states that exposure to impulsive or impact noise should not exceed a 140 dB peak sound pressure level.
How long is too long at each level #
| Level | NIOSH allowance per day | WHO weekly safe listening allowance |
|---|---|---|
| 80 dB | No limit given | 40 hours |
| 85 dB | 8 hours | 12 hours 30 minutes |
| 90 dB | about 2.5 hours | 4 hours |
| 95 dB | about 48 minutes | 1 hour 15 minutes |
| 100 dB | 15 minutes | 20 minutes |
NIOSH’s figures are per workday; the WHO’s safe listening figures are weekly totals for recreational sound. They come from different traditions, but they agree on the shape: a few decibels more buys you far less time. For the legal picture in U.S. workplaces, where the enforceable limit is 90 dBA with a 5 dB exchange rate and 85 dBA triggers a hearing conservation program, see NIOSH vs OSHA noise limits.
Which type of hearing protection should you choose? #
NIOSH groups hearing protectors into three categories: earplugs, which slide into the ear canal; earmuffs, which surround the outer ear; and canal caps, which cover the entrance to the canal.
- Foam earplugs give the most attenuation for the least money, but only if rolled down thin and inserted deep enough. Cheap enough to keep in every jacket pocket.
- Flanged or reusable plugs are easier to insert correctly and washable. Good for repeat use.
- Filtered or musician’s plugs cut the level fairly evenly across frequencies instead of smothering the highs, so music and speech stay clear while the level drops. Worth the money for concerts, bars, band practice and DJ work.
- Earmuffs are quick on and off, which suits intermittent tasks, and they’re easier to fit correctly than plugs. They’re bulky in heat and their seal is broken by glasses arms and thick hair.
- Canal caps suit tasks with frequent short bursts of noise, where you need something you can push in and pull out repeatedly.
- Electronic or level-dependent muffs amplify quiet sound and clamp loud sound, which is why shooters and ground crews use them. They still need the same fit as ordinary muffs.
For very loud environments, NIOSH recommends double hearing protection, earmuffs worn over earplugs, for workers exposed to noise levels of 100 dBA or greater.
What the NRR on the box does and doesn’t tell you #
Every protector sold in the U.S. carries a Noise Reduction Rating. Treat it as a laboratory ceiling rather than a promise. NIOSH says outright that the NRR on packaging “often does not reflect the actual protection provided for each worker,” and it has recommended derating the published number. The real-world gap comes from fit: a plug that isn’t inserted properly can give you a fraction of its rating.
Where it matters, fit testing measures the protection an individual actually gets and produces a Personal Attenuation Rating for that person with that protector. Many workplace hearing conservation programs now include it.
Two practical implications. First, a well-fitted 22 NRR plug beats a badly fitted 33 NRR plug. Second, more attenuation is not automatically better. Over-protection makes speech and warning signals hard to hear, which pushes people to take protectors off in exactly the moments they need them.
Turn the noise down before you cover your ears #
Hearing protection sits at the bottom of NIOSH’s hierarchy of controls, not the top. NIOSH’s prevention guidance says reducing noise below 85 dBA is the best way to prevent occupational hearing loss, and notes that even a 3 dB decrease in exposure lowers the risk.
- Remove or replace the noisy thing. A quieter tool, a muffler, a rubber mat under a vibrating machine.
- Put distance between you and it. NIOSH notes that doubling your distance from a source can cut the level by as much as 6 dB.
- Cut the time. Split a loud job across two days, or alternate with quiet tasks.
- Then wear protection for whatever is left.
Check the level before you decide #
Guessing is unreliable, especially after you’ve been in noise for a while and your ears have dulled. A phone reading gets you close enough to make the call.
Sound Meter dB shows the current level with A-weighting, a color band from quiet to dangerous, and the NIOSH-based safe exposure time for that level, counting down from “All day” below 80 dB to minutes at concert levels. It also tracks how long you’ve spent above 85 dB in the session, which is the number that decides whether a morning of yard work was fine. Readings are estimates rather than certified measurements, so treat a reading of 84 as “grab the plugs” rather than “you’re under the limit.” For compliance measurements, a calibrated meter or a noise dosimeter is the right instrument.
Frequently asked questions #
What NRR do I need for mowing the lawn or using power tools? #
For equipment in the 90 to 105 dBA range, any properly fitted plug or muff brings you comfortably under 85 dBA at the ear, so fit and comfort matter more than chasing the highest rating. For firearms and other impulse noise, use protection rated for shooting and consider plugs under muffs.
Do noise-cancelling headphones protect your hearing? #
Only partly, and not in the way protectors do. Active cancellation works best on steady low-frequency sound such as engine drone, and does much less against sudden or high-frequency noise. They also tempt you to play music over the remaining noise. For real exposure, use rated hearing protection.
Can you wear earplugs all day? #
Many people do, and workplace programs are built around it. Keep them clean, replace foam plugs when they stop springing back, and take breaks in a quiet area rather than in the noise. If your ears become sore, itchy or infected, talk to a clinician about a different type or a custom fit.
Does hearing protection stop tinnitus? #
Preventing overexposure is the best available way to avoid noise-related ringing, but nothing prevents it in every case, and tinnitus has other causes. If you have persistent ringing, see an audiologist rather than self-treating. Ringing in the ears after a concert covers what that symptom means.
Do children need hearing protection at events? #
Yes, at loud events, and earmuffs sized for children are the practical choice since plugs rarely fit small ear canals well. See how loud is too loud for kids.