ANR Protection

Excessive Noise Exposure is the Most Common Cause of Hearing Loss

If the noise is loud enough and lasts long enough, it can damage your hearing. The damage caused by noise is called sensorineural hearing loss or nerve deafness and can be caused by several factors other than noise. But Noise-induced hearing loss is different from other forms of sensorineural hearing loss in one important way: it can be reduced…or prevented altogether.

And prevention is simple: protection. A number of studies point to other negative health effects from long-term exposure to high levels of noise, including elevated blood pressure, heart disease and increased anxiety.

Active Noise Reduction Technology

Pro Tech Technologies utilizes the most advanced Active Noise Reduction (ANR) technology in our award-winning NoiseBuster® ANR Safety Earmuff and NoiseBuster® Noise-Canceling Audio Headphone product lines.

The NoiseBuster® ANR Safety Earmuff combines active noise reduction (ANR) with passive for maximum hearing protection in high-noise environments. The NoiseBuster® Noise-Canceling Audio Headphone offers peace and quiet for consumers in environments containing low-frequency noise, such as in an aircraft cabin, riding on the train or working out at your health club.

Noise, or unwanted sound, is one of the most pervasive occupational health problems. More than nine million workers are exposed to sound levels 85 dB and above in a variety of industries including manufacturing, transportation, agriculture, military, mining, and construction and it is estimated that that more than one million workers in manufacturing alone have developed job-related hearing impairment. Noise exposure is also problematic for do-it-yourself users of lawn equipment and power tools and for those with noisy hobbies like motor sports and hunting.

Passive Hearing Protection

Basic “passive” hearing protection devices include earplugs that are inserted into the ear or earmuffs that cover the ears. These are called passive ear defenders because they employ acoustic foam to block noise waves from entering the ear. Passive protection is very effective against some types of noise (mid- and high-frequency noise) and ineffective against other noise (low-frequency noise generated by engines, motors and fans).

Noise Reduction Rating (NRR)

The NRR is the measure of effectiveness for passive earmuffs and earplugs. The NRR number represents the maximum number of decibels (dB) that the hearing protector will reduce the sound level when worn. However, devices, the NRR cannot be taken at face value because the hearing protection level is often degraded due to the improper insertion of earplugs and wear and tear on the clamping force and ear seals of earmuffs.

For more information on methods for estimating the adequacy of hearing protector attenuation visit the Occupational Safety and Health Administration website at:

Active Noise Reduction Earmuffs

There are now hearing protectors on the market containing electronics that provide the most complete level of hearing protection. This technology, called Active Noise Reduction (ANR), addresses low frequency noise. Low frequency noise from engines, motors and fans is not easily eliminated with traditional passive hearing protection devices. Low frequency noise waves are long and carry great distances. They can penetrate passive barriers like foam earcups or even cement walls (which is why you can hear the bass of your neighbor’s stereo). By combining good passive earcups with electronics for the low frequencies, ANR earmuffs deliver the most complete hearing protection.