The intensity of air molecules excitation around the ear region can be reduced by 98% when the proper kinds of noise reduction ear muffs are used. The Noise reduction rating of these devices depends on the design and molding processes associated with their production. They are subject to tests in laboratory conditions as well as real time environment to assess their quality and reliability factors. Conformance to ANSI S-3.19 and CE-EN-352.1 standards mean the devices are recommended to be used under high intensity noise generating conditions over extended period of time.
REAT value of Noise Reduction Ear Muffs
One of the most intriguing parts of noise transmission into the human ear to reach the Cochlea region is through rear ear bone. The vibration of air molecules in this region is coupled by the sensitivity of the bone to sound waves. This means the intensity is strong enough to be felt by the bone and transmitted to the inner region of the ear to reach the Cochlea.
- The excitation of the Cochlea through bone transmission of noise waves is said to be more intense than by the sound waves entering through the ear canal. When the organ is subject to consecutive waves of impulsive noise over an extended time, it can lead to permanent hearing loss. Hence the role of Rear Ear Attenuation at Threshold value is supposed to be critical for the quality of noise reduction ear muffs.
- Higher REAT can be achieved by the design process. The coverage region has to include the rear ear bone. The sealing has to be in such a manner which can block the noise waves to penetrate the bone. At the same time care must be taken to ensure the bone is not subject to any sort of stressful condition by the device. This is ensured by using the soft foam padding around the edges and corners of the ear cup.
- The twin ear cups are held and bound together with the help of an over the head band. Vertical adjustment knobs are provided at both the ends to ensure maximum flexibility and size fitting. Users with different skull and ear sizes will be able to wear the noise reduction ear muffs without causing any sort of discomfort in the long run.
- The value of REAT is tested under varying frequencies of impulsive noise. The time gap between two blats of noise is also varied in order to test the tensile strength of the ear cup. If there are found to be any deviations in the Noise reduction, the need for changing the material composition is advised to the designer. The same conditions apply for the material selection of the soft foam pad which is used to cover the inner layers of the ear cup. Once they are made to conform to the standards, they are recommended to be fitted into the noise reduction ear muffs. ClearArmor 141001 Shooters Hearing Protection Safety Ear Muffs are designed and molded in line with the ANSI and European standards of quality parameters. They are recommended as one of the best noise reduction ear muffs.