Electronic hearing protectors resemble stereo headphones but are designed to protect ears from permanent damage caused by loud noise. They utilize electronics that minimize the damage-causing volumes using different techniques. These devices protect people who work in proximity to loud noises, from gun range enthusiasts to industrial workers working with loud machinery. Other protectors resemble hearing aids and can be worn behind the ear for the comfort of people who must protect their ears for long periods.
Electronic hearing protectors are classed by a Noise Reduction Rating (NRR). The minimum rating is 19 decibels (dB). Sharper noises generated by cutting equipment or heavier gunfire require additional protection for 20 dB. Exposure to loud noises can cause permanent hearing loss; this damage is sometimes evidenced by a ringing in the ears. In order to minimize such disability, it's important that the proper equipment be selected for the environmental conditions.
The technology reduces sound primarily by two different methods. The first method is called peak clipping. It entails the electronic hearing protectors recognizing the sharpest maximum of a sound, and acting to cut it off through muffling effects. The other method reduces sound in general through compression technology. This suits environments where continuous noise occurs.
Another type of suppression serves consumer-grade noise-canceling headphones, which are designed to minimize low-frequency sounds and vibrations such as experienced on passenger airplanes. This technology utilizes an embedded microphone to detect sound for minimization. It works in conjunction with the close seal of the ear cups.
Some of these electronic hearing protectors include radio hardware and hearing enhancers that allow users to turn up the volume to increase hearing sensitivity while still retaining their protective value against sharp noises. Cup styles vary as well, from full to chopped and beveled cups. Squared-off cups are a favorite of some because of their comfort; however, they do not offer the same protective value of the full-cup style.
Noise level and period of exposure should be considered when deciding whether electronic hearing protectors are required. Prolonged exposure to volumes that fall between the noise levels of city traffic and a lawn mower can cause permanent hearing damage, which explains why these protectors are a favorite among landscapers. Physical pain can occur with sound volumes between a lawn mower and a jet engine. The average gunshot is louder than a jet engine.
Today's electronic hearing protectors offer good design for comfort and technical functionality. Radio-equipped protectors should not be used in safety-critical environments. When it comes to protecting the eardrum and the frail bones of the inner ear from permanent hearing loss, it's better to err on the side of too much protection.