This is likely a bit more technical than you’ve experienced in the past. Most likely you’ve simply been to wear ear pro (Hearing Protection) when you are shooting. Ya don’t want to hurt your ears after all! Protecting your hearing is rather important, because if we damage it, it’s gone forever. Our ears don’t really heal from hearing loss. There are some surgeries that can correct birth defects, and hearing aids that can help once hearing loss has set in, but once we lose some of our hearing, it doesn’t come back.
Let’s dive into first, how our ears work, this way we can better understand the ways to protect them. Hearing is the ability to perceive sound through the detection of vibrations.
There are two main ways we hear:
First is the most common, sound waves (vibrations) travel through the air to the ear drum, through the bones in the ear, to the nervous system, and translated in the brain.
Second, sound waves bombard the skull and the bones in the skull carry the sound to the nerves in your ear.
When we are shooting, we are inundated with sounds waves through both air and bone conductive hearing. Gunshots are massive pressure waves and are very harmful to our ears. One way we determine how “Loud” or damaging a sound is, is by its decibel level. Decibels are rather complex and can be hard to understand. To put is as plainly as possible, a Decibel is a ratio of power and amplitude, in this case the intensity of sound waves, essentially the higher the number, the louder and more harmful the sound. An increase of 10 decibels is 10 times as loud. An Increase of 3 decibels is twice as loud. Each time you double the distance from the sound source, it reduces the decibel level by 6 decibels. This is the standard sound dissipation rate through air.
Hearing loss is considered imminent for prolonged exposure to sounds over 85db. The average conversation is held at about 65db. The average gunshot is 140-190db and can cause immediate damage. According to OSHA, you can be exposed to up to 85 decibels for a period of time not to exceed 8 hours. Over 85 decibels, we have to reduce the amount of time we are exposed to it. At about 115 decibels, we have about a half-second of permissible exposure time without any protection. Gunshots are much louder, and always require protection.
Hearing Protection, such as ear plugs and ear-muffs are examples of PPE (Personal Protective Equipment). OSHA stresses that the use of PPE is not a primary protection measure and is not to be considered as a primary solution to safety issues. They are to be considered and used when primary methods, such as engineering controls and administrative controls, fail to adequately eliminate or reduce the hazard. In construction trades engineering controls are like guards on saws, two handed operating switches, etc. In the gun world, for hearing protection, we are talking silencers and suppressors. Unfortunately, what should be regarded as the primary and safest method of hearing protection, is heavily regulated and even illegal in many states. One reason why silencers and suppressors are to be preferred over ear plugs and muff is that they reduce the noise at the source, protect more than simply an individual person, they reduce and sometimes eliminate the risk of hearing loss via both forms of hearing conduction, air and bone. Suppressors not only prevent the sound from entering your ear, but also greatly reduces the impact they have on your skull as it conducts the vibrations to the inner ear. Unfortunately, they are taxed, regulated, and placed out of reach for many Americans.
Standard hearing protection, whether they be plugs or muffs, comes with a Noise Reduction Rating (NRR) Number. This NRR number means that, when the product is used properly, it will reduce any noise according to the following equation: (NRR-7)/2=X
For instance, a 165db gunshot, while wearing 30NRR ear plugs is 153.5db. Silencers and suppressors on the other hand, reduce the sound output of the weapon, most manufacturers aim for a 20-40 decibel reduction of sound output. This means that same 165db gunshot could be a 135db gunshot with the addition of a 30db reduction suppressor. Ear plugs and muff prevent the sound waves (vibrations) from entering the ear and impacting the ear drum. Muffs provide a little more surface area for guarding against the bone conductive hearing loss, however neither are rated to reduce the impact of potential hearing loss from bone conduction.
As you can see, PPE really does have its limits on effectiveness. We can increase its effectiveness by doubling up and wearing Muff over Ear Plugs. This effectively adds 5NRR to the highest NRR rating of the PPE we are using. For example, if we have 30 NRR foam ear plugs, and 23NRR ear muff, our total protection is 35NRR. This would bring that 165db gunshot down to 151db.
Foam ear plugs are among the most common and misused hearing protection. None of these options will be effective if they are not used properly. It’s important to use them correctly. Foam Ear Plugs are often not inserted deep enough and therefore compromise the protection they offer. Here is a simple three-step procedure to ensure you use foam ear plugs effectively.
- ROLL the ear plug into a small snake with your fingers.
- PULL the top of your ear with your opposite hand to straighten your ear canal. This will help the ear plug side right in.
- HOLD the ear plug in for about 30-40 second until it is fully expanded.
If you follow these steps, the ear plug should not be visible from a person looking at you from in front. If you cup your hands over your ears and the sound is more muffled, then your earplugs likely are not in all the way.
Ear Muffs need to have a good seal around the ear to be effective, things like hats, the ear hooks on your glasses, hearing aids, etc can break that seal compromising your protection. Make sure the foam or gel pads are in good shape, not cracking, and situate the ear muffs to sit flat over your ears for the best seal.
To effectively protect your hearing, we recommend considering the following.
- Use Silencers and Suppressors, when available.
- Ensure PPE fits effectively and is in good working order.
- Double up on ear pro (ear plugs with muffs on top), especially for louder high power firearms, firearms with muzzle breaks, or indoor ranges.
- Keep your distance, distance is your friend. If you are spectating, hang back a bit and let the air reduce the sound impact for you.
- Minimize your time spent on the firing line.