NRR and SNR are different standardized noise-reduction rating systems. Compare NRR with NRR and SNR with SNR. A higher number under one system cannot be treated as a directly equivalent advantage over a number under the other.
Neither label is a measurement of the attenuation you personally receive while sleeping. Fit and the noise being considered matter, and a product rating does not establish overnight comfort or whether you will hear an alarm.
Why one product can have two numbers
Loop’s published Quiet 2 figures are 24 dB SNR and 14 dB NRR. These describe the same product under different rating systems. They are not two user-selectable protection modes and are not measurements made by this site.
A NIOSH/CDC-hosted research paper on personal attenuation discusses NRR and the ISO 4869-2 SNR approach, along with the effects of fit and noise spectrum. The different figures should not be collapsed into a fixed conversion rule for every earplug.
What each piece of evidence establishes
| Evidence | What it supports | What still needs separate evidence |
|---|---|---|
| A published NRR | The product’s rating under that system | Your fit, actual exposure and relevant use conditions |
| A published SNR | The product’s rating under that system | Your fit and a comparable same-system assessment |
| Individual fit-testing result | Attenuation assessed for the person and test conditions | Continued correct use and the applicable exposure assessment |
| Comfort or alarm claim | Only what the specific evidence actually evaluates | It cannot be inferred from NRR or SNR alone |
Do not simply subtract a package rating from a bedroom sound reading to declare the sound reaching your ears. This guide provides no household attenuation calculator or fixed NRR-to-SNR conversion.
Fit-testing guidance has changed
NIOSH’s 2025 individual fit-testing update recommends individual fit testing for occupational decisions and supersedes its 1998 derating guidance. An older article repeating that earlier formula should not be treated as the current NIOSH recommendation.
That is workplace guidance. It does not turn a home comfort check into an occupational fit test, nor does it establish that a particular earplug is appropriate for every sleeping situation. For workplace protection, use the applicable exposure assessment and fit-testing process rather than choosing from the largest package number alone.
Keep sleep questions separate from rating questions
For a sleep-oriented comparison, record the exact product, both labels where supplied, the manufacturer’s fitting directions, and the questions the ratings leave unanswered. Those can include overnight comfort, correct fit during use and awareness of needed signals.
We have not measured those outcomes. Follow the exact product’s directions, and do not assume that a laboratory rating proves a comfortable seal for your ear or guarantees alarm audibility.
The Loop Quiet 2 research-based review provides the product-specific context. Its published labels remain distinct from a personal attenuation or overnight-comfort measurement.
Method and limits
We reconciled a research paper, current NIOSH guidance and Loop’s published labels, checked October 11, 2026. This is a rating-reference guide, not a hearing-protection compliance verdict or a sleep trial. Use like-for-like labels for the initial comparison and keep personal attenuation and comfort evidence distinct.
Sources
See Also
Turn this advice into a better bedroom setup with Air Purifiers for Light Sleepers: Noise and CADR Checklist, Dehumidifier for a Bedroom, and Why Cooling Mattress Pads Can Feel Warm, Damp or Musty After Washing.
For the next decision on comfort, sound, temperature, or room air, continue with Water-Cooled vs Gel Mattress Pads: Active and Passive Cooling and Best Mattresses for Every Sleep Style.