Since the1980s, the most common criterion for hearing protection in the United States has been the Noise Reduction Rating, or NRR. Hearing protection devices sold in the United States are required by law to display the NRR on their label. Though the idea of a single number to aid in choosing hearing protection seemed like a good idea to aid in product selection, actual application has been challenging.

The EPA has finally, after nearly 30 years, published a proposed new rule for hearing protector labeling based on experience from the past three decades and the publication of two new ANSI standards (see The Roadmap to the Rulemaking Process). Experts in the field of hearing protection have reached consensus on a revised American National Standard, "Methods for Measuring the Real-Ear Attenuation of Hearing Protectors, ANSI/ASA S12.6-2008." It contains significant changes to the previous edition of the standard, published in 1997, and its Method A will form the basis for the new testing process that the EPA has proposed.

In the coming months, there will be a public hearing and public comments, and a subsequent final rule. These requirements will then be incorporated into product labels. 3M/E-A-R experts Ted Madison and Elliott Berger have been involved in the process, and as additional information is released, you will find the latest updates here. In the meantime, you'll find a number of articles and background information, as well as answers to your questions, posted on this site.

Additional Information

To stay informed about pending changes to the Noise Reduction Rating and related technical issues, be sure to sign up for email updates. Copies of ANSI/ASA S12.6-2008 are available for purchase from the Acoustical Society of America (ASA) online standards store at asastore.aip.org or by calling ASA at 1-800-874-6383.

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