New Proposed EPA Noise Reduction Rating

In an effort to bring the Noise Reduction Ratings (NRR) of hearing protection devices more in line with real-world usage, the United States Environmental Protection Agency (EPA) will soon announce a proposed new regulation for the labeling of hearing protection devices (HPD).*

Since rating methods are based upon idealized laboratory testing, the NRR has been criticized for being too generous in its prediction of noise reduction (attenuation). While some workers in real-world worksites achieve the stated NRR on the package, many workers do not. This has led to a variety of inappropriate de-rating methods for hearing protectors, and has contributed too much confusion in knowing how to accurately estimate a hearing protector's attenuation.


Under the proposed regulation, a new rating system will be used. While it will be known as the NRR, it will now represent a range of expected protection, as opposed to a single-number estimate. While the proposed method still uses ANSI-standard lab testing to generate the attenuation ratings, the new Noise Reduction Rating will provide an indication of how much attenuation minimally trained users (the lower number) versus highly motivated, trained users (the higher number) can be expected to achieve. For some hearing protectors, the spread of this range may be quite significant.

In addition to a new NRR, the proposed EPA regulation would address for the first time the rating of non-standard hearing protectors, such as Active Noise Reduction or level-dependent (or impact noise) protectors. Under the old labeling requirements, these specialized protectors were rated with a low NRR, simply because they were not tested in the higher noise ranges where their noise reduction capability is activated. The EPA is expected to include these types of hearing protectors in its new labeling regulation so that purchasers can make informed choices.

Questions and Answers

Why did the EPA decide to make this change?
Since 1974, the U.S. Environmental Protection Agency (EPA) has used the Noise Reduction Rating (NRR) as its yardstick to measure hearing protector effectiveness in reducing noise levels. But since it is based upon idealized laboratory testing, the NRR can overestimate the protection received by many workers. Like the EPA’s new mileage estimation for cars, which takes into consideration a variety of usage factors, the new Noise Reduction Rating will take into better consideration the human factors involved with the use of HPDs — specifically training and fit.

Why is a two-number range part of the new label?
A two-number range on the label is a more realistic indicator of the variety of protection levels achieved by users in the real world, depending on the users training and fit. In the past, some safety managers assumed that the attenuation rating on the product package would be achieved by most workers, regardless of training or motivation. But the two-number range now clearly shows that employees who do not achieve a proper fit will obtain attenuation nearer the low end of the range, while those employees who do achieve a proper fit will be nearer the high end of the range.

Will the OSHA 29 CFR 1910.95 Occupational Noise Standard change as well?
OSHA has not announced any proposed changes to the Occupational Noise Standard. Although the EPA and OSHA operate independently of each other, OSHA will presumably respond to the revised NRR label by issuing a field directive or technical memorandum, informing its compliance officers how to deal with the new two-number NRR range.

When will the new NRR range take effect?
After the proposed rule goes through public comment and the EPA issues a final regulation, there will be a transition period for manufacturers to re-test and re-label packaging with the new rating.

Will earplugs and earmuffs undergo more frequent NRR testing?
The new regulation requires HPD manufacturers to re-test their earplugs and earmuffs on a periodic basis to ensure accurate attenuation.

Does the new NRR affect the octave band data chart that appears on HPD packaging?
No, the octave band data chart will still appear on HPD packaging, and will remain essentially unchanged.

Will the new ratings favor earplugs or earmuffs?
While a well-fit foam earplug generally has greater attenuation than most earmuffs, earmuffs are inherently easier to fit for most users. There is less variability in the fit of earmuffs, and therefore, the overall range of attenuation for earmuffs will be usually be tighter, and often higher, than earplugs. In a comprehensive Hearing Conservation Program, workers should be offered a choice of earplugs, bands and earmuffs that meet the noise reduction requirements of the work environment.

What should we be doing now to prepare for this change?
Although the new labeling regulation takes effect whenever the final rule is published by the EPA, there are a number of things you can be doing now to prepare. Depending upon the new NRR range of re-labeled hearing protectors, it may be necessary to re-evaluate your hearing protectors to determine whether they are appropriate for your noise environment. Most importantly, you can begin right now to provide better training to your workers in the proper fit of hearing protectors.

How do I know if the HPDs I currently offer my employees are appropriate?
The new two-number NRR label is a better estimate of real-world performance, but it also raises a critical question for safety managers: how much protection are my workers achieving? If the NRR range is 18-30 dB, are they obtaining attenuation closer to the low end or the high end of the range?

This new change provides you with an ideal opportunity to perform fit testing on your employees’ earplugs to determine if they are receiving optimal protection for their noise environment.

In addition, Howard Leight’s online Hearing Protector Selector offers information on earplugs and earmuffs based on your specification, such as noise levels, style and feature requirements. To access the Hearing Protector Selector, please visit

*While the EPA has not made an official announcement about the proposed change to the Noise reduction Rating, information about the change has been made public in a variety of public meetings, conferences and papers. 3/09

Information courtesy of Howard Leight ® Division/ Sperian Hearing Protection, LLC

Webinar Series Dr. Theresa Schulz, Hearing Conservation Manager with Sperian Hearing Protection and Brad Witt, Director of Hearing Conservaton at Sperian Hearing Protection, discuss occupational noise exposure. Also hear insight on the updated 2009 NRR system.

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