Active hearing protection for public safety By: Ron LaPedis

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Hearing protection of choice (e.g., noise-reducing earplugs, ear canal caps or earmuffs) is a must for every pubic safety professional while doing work that exposes you to high-decibel noise sources.

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Most firefighters wear over-the-ear muffs, sometimes with built-in microphones and comm links, while in their apparatus since they most always run Code 3 to an incident. LEOs, SWAT, hazmat, and search and rescue personnel also need to protect their hearing but they don’t always know when they will need hearing protection. And by the time they know it’s needed, it might be too late to take a time-out to put them on.

As someone who has hearing loss and tinnitus due to unprotected exposure to an explosion, I know how important it is to not lose your hearing in the first place and to mitigate any hearing loss if it already exists. Traditional hearing aids for people without severe loss sit behind the ear and have a tube or wire extending into the ear. While I wear these every day, they cannot be used with shooting muffs, nor do they provide protection from loud noises.

Your hearing is precious and not something to take for granted.Your hearing is precious and not something to take for granted.
Your hearing is precious and not something to take for granted. (Photo/Ron LaPedis)

While passive generic or custom in-ear plugs or over-the-ear muffs are available, they may inhibit situational awareness, possibly putting you in harm’s way. And for anyone with existing hearing loss, passive hearing protection makes a conversation even less understandable since most hearing aids need to be removed before you can use them.

Active hearing protection

Many shooters have electronic muffs that don’t impact situational awareness. Some muffs even give you “bionic” hearing by boosting sounds and increasing directional awareness while still offering protection from loud sounds.

But depending on what you are doing, active muffs can get in the way. While firefighters can wear muffs on the job, some sniper rifles are nearly impossible to shoot with the needed precision while wearing muffs.

This is where custom-molded and custom-programmed active in-ear protection excels. There are a handful of manufacturers on the market, and you need to figure out the brand and model that will work for you.

Before purchasing custom in-ear protection, consider a trip to the audiologist. Many insurance plans will pay for audio testing, but if yours won’t, most Costco stores have licensed audiologists with reasonable charges. This first step will let you know if you already have some hearing loss. The result of a hearing exam is a chart showing your hearing response. A mirror image of this chart is your prescription, with the “missing” frequencies boosted by the hearing aid.

This chart shows the result of a hearing exam. Note the loss in the left ear (blue).This chart shows the result of a hearing exam. Note the loss in the left ear (blue).
This chart shows the result of a hearing exam. Note the loss in the left ear (blue). (Photo/Ron LaPedis)

Brand names aside, as the price goes up, so do the features. Some questions to ask are:

  • How much sound reduction (usually in dB – decibels)? A minimum of 30 dB is good.
  • How many different modes are there and what do they do?
  • What battery does it use and how long does it run?
  • What do I need to supply to the manufacturer for customization?
  • What is the warranty both for initial fit and operation?
  • Is it Bluetooth compatible?
  • Will it work as an earpiece with my radio?
  • Are discounts available for first responders?

If you already have hearing loss, ask these additional questions:

  • Is the device programable to my prescription?
  • Can it be reprogrammed and how much does it cost?
  • How many channels (equalization bands) does it offer? The more there are, the more accurately it can be tuned to your specific requirements. You can think of this as something like your audio system’s equalizer.

At the 2022 SHOT Show, I decided to put down a few thousand dollars and I bought two pairs of custom in-ear hearing protection. The Axil Extreme Edge Blue and the Tactical Hearing T-4-16-HD. Both have 4 modes (enhancement, protection, enhancement + protection and maximum protection) and are programmable to your prescription, which you send to them along with molds of your ears taken by an audiologist. Each is available in several shell and plate colors. I chose the traditional blue (left) and red (right).

Left: Axil Extreme Edge Blue; Right: Tactical Hearing T-4-16-HD. Many manufacturers offer substantial discounts to active first responders if you ask.Left: Axil Extreme Edge Blue; Right: Tactical Hearing T-4-16-HD. Many manufacturers offer substantial discounts to active first responders if you ask.
Left: Axil Extreme Edge Blue; Right: Tactical Hearing T-4-16-HD. Many manufacturers offer substantial discounts to active first responders if you ask. (Photos/Ron LaPedis)

The Extreme Edge Blue is available in two versions: in the canal or full shell which fits in your ear’s concha. See Figure 1 for a size comparison between the full shell (left) and in canal (right). Since it is substantially larger, the full shell version uses a longer-lasting 312 battery. It also offers 16 channels. Some versions are Bluetooth-enabled and can be paired with your smartphone or some public service radios.

The T-4-16-HD is as small as they come and nearly fits inside the ear canal. It offers 16 channels and takes a #10 battery, which will last about a week if you remember to open the battery door when not in use.

Figure 1: Left and right photos both show a full ear (concha) and canal protector. Full shell models allow for bigger, longer-lasting batteries.Figure 1: Left and right photos both show a full ear (concha) and canal protector. Full shell models allow for bigger, longer-lasting batteries.
Figure 1: Left and right photos both show a full ear (concha) and canal protector. Full shell models allow for bigger, longer-lasting batteries. (Photo/Ron LaPedis)

Do they work?

Figure 2 shows the results of a sweep test conducted by audiologist Anga Lao, AuD, which uses a small tube inserted into the ear canal. Various sounds and tones are played by a speaker in front of the subject and the machine records the amplitude inside the ear without plugs (green) and with plugs (purple). The yellow line is the difference or actual noise reduction. I covered the Westone DefendEar here and added them for comparison.

Figure 2: Results of a sweep test showing the 30-35 dB noise reduction of three in-ear hearing protectors.Figure 2: Results of a sweep test showing the 30-35 dB noise reduction of three in-ear hearing protectors.
Figure 2: Results of a sweep test showing the 30-35 dB noise reduction of three in-ear hearing protectors. (Photo/Ron LaPedis)

The average noise reduction varies from 30-35 dB and my hearing was protected by all three products. You can see that the in canal (Axil) and concha (Tactical Hearing and Westone) provide similar noise reduction, meaning that you can choose the fit that you prefer and still be protected.

Dr. Lao shared that it is important to note that all three of my custom plugs were built similarly – with a deep canal fit and a good seal. Regardless of the plug or style you prefer, make sure the canal portion is a deep and well-sealed fit or you will not get the full noise reduction the plugs are rated for. Another good reason to work with an audiologist!

Bone Conduction Hearing

In-ear plugs, whether in canal or concha, provide everyday protection and can be used at outdoor ranges with most firearms. However, we hear via two different routes. The first is through our ear canal and eardrum, or via air conduction. But we also hear via bone conduction where the sound waves are sent through our skull directly into the inner ear, bypassing the ear canal completely. This means that in-ear plugs may not protect our hearing from louder weapons or explosions.

This also is why we hear our voices differently on a recording versus when we speak. The outside world’s perception of our voice (all through air conduction) is a mismatch with what we hear ourselves. Since we hear our own voice as a blend of some air conduction but mostly bone conduction, we get a low pitch boost – thus hearing our own voice with more bass and richness.

The more you physically can dampen your head to harmful levels of sound energy the better it will protect your inner ears from acoustical trauma. Properly fitted over-the-ear muffs or helmet liners rest on and dampen the vibrations hitting the bones around your ear which are most tied to your inner ear.

Fun fact: In theory, no matter where the sound energy hits your skull the intensity is the same when delivered to both cochleae. The entire skull including cochleae is one fused unit. Audiologists can diagnose your type of hearing loss by comparing your air and conduction hearing results.

Just like you can combine foam plugs with muffs, you also can combine active in-ear protection and muffs. The active in-ear plugs mitigate my hearing loss and combining them with muffs protects what’s left of my hearing while allowing me to listen to my students and hear range commands. I also maintain situational awareness that I otherwise would lose without my hearing aids.

Final thoughts

Remember to ask for discounts from a supplier since many offer substantially discounted non-published pricing to first responders. My health insurance paid a little bit toward my plugs because of my documented hearing loss. You should check with your agency, union rep or insurance because many will partially or fully cover hearing aids or hearing protection. One previous employer paid up to $4,000 every three years for hearing aids.

Your hearing is precious. In this article, Johns Hopkins expert Frank Lin, MD, Ph.D., and his colleagues write that mild hearing loss doubled dementia risk. Moderate loss tripled risk, and people with a severe hearing impairment were five times more likely to develop dementia.

For more information about hearing protection, check out this page on Police1.com.