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Hearing protection: how to choose (and what NRR means)

For any regular exposure above 85 dBA, rated hearing protection is the answer. But the number on the box is optimistic — the real-world reduction is roughly (NRR − 7) ÷ 2, so a 33 NRR plug gives about 13 dB in practice. Fit matters more than the rating.

Earplugs and earmuffs used for hearing protection against loud noise — Foam plugs offer the highest raw NRR; electronic muffs let you hear speech while blocking peaks.

Hearing damage from noise is painless, gradual and permanent — and entirely preventable. The single most useful skill is reading a protector's rating correctly, because the headline number overstates what you actually get.

NRR vs SNR

The US uses the Noise Reduction Rating (NRR) in decibels; Europe uses the Single Number Rating (SNR). Both estimate attenuation, but neither is what you get in the field. OSHA recommends de-rating the NRR: effective reduction ≈ (NRR − 7) ÷ 2. So a 30 NRR muff gives about 11–12 dB in real use, not 30.

Try it: protection calculator

Estimate the level reaching your ear after de-rating.

Noise level (dBA)

Protector NRR (dB)

Enter the noise level and the NRR rating.

Which type for which job

Type	Typical NRR	Best for
Foam earplugs	29–33	Sleep, travel, DIY — highest raw attenuation, needs correct rolling & insertion
Filtered/musician plugs	~20 (flat)	Concerts & musicians — reduces evenly so music stays clear
Passive earmuffs	22–31	Mowing, workshops — easy on/off, consistent fit
Electronic earmuffs	22–26	Shooting, machinery — amplify speech, clamp down on sudden bangs

Hearing protection

For anything above 85 dB, rated protection matters. Look at the NRR (US) or SNR (EU) figure — real-world reduction is roughly (NRR − 7) ÷ 2.

Electronic ear muffs (NRR 22–25)Shooting, mowing — amplify speech, block bangsLink coming soon

Reusable filtered earplugs (NRR 20)Concerts & musicians — flat attenuationLink coming soon

Foam earplugs (NRR 32)Sleep, travel, DIY — highest raw NRRLink coming soon

As an affiliate we may earn from qualifying purchases. This never changes our data or recommendations.

How much do you need?

The goal is simple: get the level at your eardrum below 85 dBA. Read your exposure in the exposure calculator, subtract the de-rated protection, and check the result is under 85. For very loud environments (105 dB+), plugs plus muffs together add about 5 dB over the better device alone — the standard approach for firearms and heavy machinery.

Noise-cancelling headphones

Active noise cancellation (ANC) cuts steady low-frequency noise — planes, trains, HVAC hum — by 20–30 dB, letting you listen at safer volumes.

Over-ear ANC (premium)Best cancellation for travel & officesLink coming soon

Wireless ANC earbudsPocketable, great for commutingLink coming soon

Budget ANC over-earSolid cancellation under $100Link coming soon

As an affiliate we may earn from qualifying purchases. This never changes our data or recommendations.

Frequently asked questions

How much does hearing protection actually reduce noise?

Far less than the label suggests. OSHA de-rates the NRR with (NRR − 7) ÷ 2, so a 33 NRR earplug realistically gives about 13 dB in everyday use. Fit is everything — a poorly seated plug can give almost nothing.

Can I double up plugs and muffs?

Yes. Wearing earplugs under earmuffs adds roughly 5 dB over the higher-rated device alone (not the sum of both). This is standard practice above about 105 dB.

What NRR do I need?

Enough to bring your at-ear level below 85 dBA. Use our NRR calculator: for 100 dBA you want an effective reduction of at least 15 dB, which means an NRR of about 37 after de-rating — or doubling up.

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Sources & accuracy. Reference levels are drawn from published data by NIOSH, OSHA, the CDC, the WHO Environmental Noise Guidelines and the American Speech-Language-Hearing Association (ASHA). Real-world readings vary with distance, room acoustics and the specific source, so treat every figure as a typical value rather than an exact constant. Last reviewed 2026-08-11.