Many hearing protection devices have Noise Reduction Ratings or NRR for short that show you how much decibels will be suppressed from a loud noise/ environment. So what does noise reduction rating mean in terms of hearing protection?
We'll get there but first, you must know how hazardous noise can affect your hearing.
Hearing protection devices are to be tested and approved by both the Occupational Safety & Health Administration (OSHA) and the American National Standards (ANSI). According to the National Institute for Occupational Safety & Health, over 22 million workers are exposed to hazardous noise levels at work each year in the United States.
Moreover, hearing loss disability results in an estimated $242,000,000 in workers’ compensation payments annually. Hearing damage is an invisible disability that not only negatively impacts an individual’s health and well-being, but it creates an occupational safety risk for everybody.
You need to understand how much decibel sound reduction your headset is providing you and knowing what the noise reduction rating is and how it’s calculated so you are always protected from loud noise.
What is Noise Reduction Rating (NRR)?
Noise Reduction Rating is a unit of measurement that determines the efficiency of hearing protection devices that reduce sound exposure. Sound is measured in decibels (dB). The higher the decibel level the louder the noise is. The lower your sound decibel exposure the better.
People use hearing protection headsets, earmuffs, and earplugs with various levels of NRR to help reduce the level of noise exposure in an environment.
What is a Good Noise Reduction Rating?
You may be asking yourself, what’s a good noise reduction rating?
This depends on the type of hearing protection your wearing. The highest NRR Rating for earplugs is 33 while the highest NRR rating for earmuffs is 31. If you use double hearing protection, like combining earplugs with an earmuff the highest level of NRR protection you’ll get is 36. The higher the NRR rating, the greater the noise reduction capabilities.
All in all, NRR functions as a ruler for how effective hearing protection equipment reduces noise in real-time and space. Refer to the diagram below for a visual guide to NRR:
How Do You Determine NRR?
As stated before, noise reduction ratings help reduce the decibel sound levels in a loud environment. To figure out how much of the decibel will be reduced with your headsets NRR requires some math.
The noise reduction rating is calculated by using a simple subtraction and division equation. First, take the NRR of your hearing protection device, subtract seven, and divide by two. The full equation can be found below,
For example, we will take an earplug with an NRR of 23, after completing the equation above we come up with 8. So, we can determine that the earplugs will reduce the decibel volume by 8.
To put that in context, if your around heavy machinery with a dB of 110 (extremely loud), your new dB volume is 102 dB. Remember, hearing protection is always recommended for constant exposure and sounds over 90 decibels. This brings us back to questioning what a good NRR rating is, consider this when deciding a hearing protector device and their NRR.
When using double hearing protectors, earplugs with headsets, you can increase the noise reduction rating. To determine the overall noise reduction rating for double hearing protection, you won’t be adding the two numbers together. Rather, you’ll add five more decibels of protection to whichever has the highest NRR.
Being, if you wear earplugs with an NRR of 28 and a headset with an NRR of 20, add 5 to the earplugs NRR, 28, and your new NRR is 33 dB.
Decibel Level Chart
How loud is too loud?
See just how loud your surroundings are by looking at our decibel level chart. This should show you the level of hazardous noise around you and help you determine the correct noise reduction rating you might need.
Which Industries Should Wear Hearing Protection?
While hearing protection is extremely important for anyone exposed to high levels of noise for an extended period and exposure over 90 decibels, anyone working in high noise industries below should always be protected.
It should come as no surprise that manufacturing floors ring with a constant combination of loud machinery, clanking metal, compressed air, and all the other sounds that go into the production of goods.
Statistics show that 80% of manufacturing workers suffer from some level of hearing impairment, the majority occurring within the first decade of employment. The manufacturing industry has a high demand for hearing protection equipment.
These three industries vary greatly; however, they all share the common thread of work-related hearing loss. The tools utilized here operate as high as 115 dB (well above the recommended limit of 85 dB), and lack of oversight along with seasonal employment has made it difficult to fight hearing damage.
For workers in these industries, we recommend that hearing protection be implemented at an individual level to remain protected.
The levels of hearing impairment among military veterans have reached that of an epidemic. Although some soldiers might only deploy for a short period of time, the gunfire, explosions, and aircraft engines regularly associated with warfare can leave a lasting impact on one’s quality of life.
The Hearing Health Foundation conducted a study showing that over 60% of returning combat troops from Iraq & Afghanistan suffered from noise-induced hearing loss – the most common service-related disability. As a result, the Department of Defense has initiated the development and implementation of more advanced hearing equipment to protect those serving our country.
Over a third of farmers in the United States have hearing loss. The loud sounds of combines, tractors, livestock, and other equipment are experienced from a young age, continuing daily if they work their farm.
Federal agencies and local groups have taken steps to educate the younger generation of the importance of hearing protection as well as a push for manufacturers to improve noise reduction, however, the issue remains to be fully addressed.
The industries above are just to name a few, other industries who need to be wearing proper hearing protection are,
- Aircraft Maintenance Workers
- Musicians/ Entertainment
- Factory engineers
- Sport game officials
Tips for Protecting Your Hearing
In addition to wearing proper hearing protection, you should be following other tips for protecting your hearing too.
Take breaks and Limit the amount of time without proper hearing protection
- Move away from loud noise every 15 minutes and give your hearing an applicable amount of time to recover before exposure again.
- Wear earplugs and headsets properly
Wearing your earplugs and headsets the correct way ensures you are getting the most protection to prevent hearing loss.
4 Best Earplugs and Headsets for Hearing Protection
- NRR – 30 dB *Highest NRR Rating Possible
- In-ear tactical communication
- 3M classic earplugs provide protection & enable the user to hear in noisy environments
- 10 EA/Case
The 3M Peltor Tactical Earplug improves situational awareness & communications in challenging environments. Wireless connectivity for monitoring radio or cell phone sound sources. Two-way communication through shoulder microphones and cell phone is maintained.
- Able to receive audio signals wirelessly from neckloop accessory (purchased separately)
- Provides hearing protection
- Environmental Microphones (level-dependent function)
- Rechargeable via Micro-USSB or 3 AA Batteries
- NRR – 23 dB
- Designed specifically for users working in high-noise environments
- Deep earcup for all-day comfort
- NRR – 19 dB
- Small, compact, & foldable for easy storage
- Separate microphone, receiver, amplifier, & volume control in each ear cup gives true stereophonic reception
- Natural Interaction Behavior (NIB) for peer-to-peer headset communication
- Omni-directional environmental microphones for level-dependent situational awareness
- Mission Audio Profile (MAP) to select audibility settings based on anticipated noise exposure
- NRR – 20 dB
At First Source Wireless, we are a certified dealer of 3M, a top leader in tactical hearing protection headsets. 3M headsets are manufactured and used for many types of industries such as construction, manufacturing, military, and law enforcement. Give us a call today to discuss how 3M Peltor headsets can protect your hearing now.
Updated: November 22, 2020
About the Author
Taylor Thomas is a Marketing Manger at First Source Wireless. With her experience in hearing protection, she has informed public safety professionals with resources on Noise Reduction Ratings. Taylor has also attended many conferences including International Association of Chiefs of Police (IACP), Association of Public Safety Communications Officials (APCO), and International Wireless Communications Expo (IWCE).