Decibel Levels Chart

Do the math on your own exposure: our free noise exposure calculator turns any dBA level and duration into OSHA and NIOSH dose percentages, allowed time, and derated NRR protection.

What is a safe decibel level and when is hearing protection required?

Published June 22, 2026 · Last updated July 27, 2026

Short answer: Sound below about 70 dBA is generally safe for unlimited exposure; damage risk begins around 85 dBA and rises sharply above it. OSHA's noise standard requires hearing protection once an 8-hour time-weighted average reaches 90 dBA, and a hearing conservation program at 85 dBA. This decibel levels chart shows where common tools fall and how long you can be exposed before protection is mandatory.

For an activity-by-activity answer — mowing, shooting, concerts, power tools — see our companion guide on when do you need hearing protection.

Noise damage is cumulative, permanent, and entirely preventable. The decibel (dB) scale is logarithmic, so every 10 dB increase represents a tenfold jump in sound intensity — which is why a jackhammer is not "a bit louder" than conversation but roughly a million times more intense. OSHA's occupational noise standard, 29 CFR 1910.95, and the stricter NIOSH recommended exposure limit set the thresholds this decibel levels chart is built around. This guide is written for safety managers, supervisors, and trade workers who need to know which tasks require hearing protection and how to choose it. We chart noise sources by dBA, lay out the OSHA exposure limits, and show how to convert a noise level into the right NRR.

Why this matters.
Noise-induced hearing loss is the most common recordable occupational illness, and it is irreversible — there is no surgery or hearing aid that restores damaged cochlear hair cells. OSHA 29 CFR 1910.95 requires employers to act at 85 dBA and to provide protection at 90 dBA, and the CDC estimates millions of U.S. workers are exposed to hazardous noise every year. Reading the chart correctly is the first control.

How the decibel scale works

Sound pressure is measured in decibels (dB); occupational noise uses A-weighting (dBA) to match how the human ear responds. Because the scale is logarithmic, the numbers do not add the way you would expect: two machines at 90 dBA each combine to about 93 dBA, not 180. The practical takeaway is that small-looking increases are large real increases, and the safe exposure time roughly halves for every few dB above the limit.

Decibel levels chart: common noise sources

Approximate A-weighted levels for everyday and worksite sounds. Use it to estimate whether a task crosses into the hazard zone:

Any task in the highlighted rows or below needs hearing protection from our Hearing Protection range — Foam Ear Plugs for high-attenuation tasks and Ear Muffs for intermittent exposure.

Different trades call this same reference by different names — a noise level chart, a sound level chart, or simply a dB chart. Whatever the label, it answers the same two questions: how loud a source typically is in dBA, and how that number compares with the occupational exposure limits decoded in the next section.

OSHA permissible exposure limits decode table

OSHA 1910.95 sets the permissible exposure limit (PEL) at 90 dBA for 8 hours and uses a 5 dB exchange rate — for every 5 dBA increase, the allowed time halves:

NIOSH recommends a stricter 85 dBA limit with a 3 dB exchange rate. The 85 dBA "action level" is where OSHA requires a hearing conservation program — covered in the OSHA 1910.95 hearing conservation guide.

OSHA decibel limit chart: PEL vs action level at a glance

Two numbers govern workplace noise in the United States, and they are often confused. This compact decibel limit chart separates them, alongside the stricter NIOSH recommendation:

How to use the chart to choose hearing protection

1. Identify the noise level. Measure with a sound level meter or dosimeter, or estimate from the Part 2 chart.
2. Find the exposure limit. Use the Part 3 table to see how long that level is permissible.
3. Calculate the reduction needed. Subtract your target safe level (85-90 dBA) from the measured level to find the attenuation required.
4. Convert to NRR. Apply the OSHA derating to the printed Noise Reduction Rating — see the NRR guide for the math.
5. Select and fit. Choose an earplug or earmuff with adequate NRR and insert it correctly — see how to insert foam earplugs.

Worked example: protecting a worker running a chainsaw

A landscaper runs a chainsaw at roughly 110 dBA. From Part 3, the unprotected limit at 110 dBA is just 30 minutes — far short of a workday. Here is the selection on real SKUs:

1. Determine the gap. To bring 110 dBA down to a safe 85 dBA at the ear requires about 25 dB of real-world attenuation.
2. Pick high-NRR foam plugs. The Howard Leight Maximum Max-1 (NRR 33) or Howard Leight Laser Lite (NRR 32) give the highest foam attenuation; even after derating they clear the 25 dB requirement.
3. Or choose reusable plugs. The Moldex 6800 Pura-Fit (NRR 33) is a high-attenuation foam option from the NRR 33 ear plugs range.
4. Add muffs for impulse spikes. Pair plugs with the 3M H10A Peltor Optime 105 ear muffs for dual protection when felling near other equipment.
5. Verify the fit. Attenuation only counts if the plug is seated correctly — follow the foam earplug insertion steps, and compare options in the highest-NRR earplug guide.

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Further reading on this site

• What is NRR? — how to derate the rating to real-world attenuation.
• OSHA 1910.95 hearing conservation — monitoring, action level, and program rules.
• How to insert foam earplugs — roll, pull, hold for full attenuation.
• Hearing protection — full lineup of plugs and muffs.
• Highest NRR earplugs — top NRR 33 picks ranked.
• Best hearing protection — complete buyer's guide.
• Ear muffs — passive and electronic options.

Related reference

Closely related on this site: when do you need hearing protection? noise levels, the 85 db rule &, what is nrr noise reduction rating explained, what is osha 29 cfr 1910.95? hearing conservation explained, ear plugs vs ear muffs: which hearing protection do you need?, best in ear hearing protection for shooting, and electronic vs passive ear muffs: which do you need?.

Why trust WC Safety

WC Safety is an independent, affiliate-supported review site. It is not a retailer: it holds no inventory, takes no orders, and earns only from qualifying purchases through clearly marked links — which never changes what a product is rated to do. Standards language is taken from the regulation text directly, and ratings are reported as the manufacturer publishes them. We run no laboratory and perform no testing of our own. Where published sources disagree, we say so and plan on the conservative figure rather than the flattering one.

Our methodology

Figures come from the regulation and the published specification, in that order. Derated numbers are calculated, not estimated. Nothing here is presented as a measured result, because we measure nothing.

Researched and written by Steven Eaton, editor of WC Safety. Steven holds no safety certification and does not test products; this page compares what manufacturers and regulators publish, with the gaps in that record marked. Last reviewed August 2026.

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