#30285 Over & Out® Stereo Electronic Hearing Protection
This product was originally developed for shooting sports where it is necessary to protect hearing from sudden loud noises but also allow unrestricted hearing of safety commands. Needless to say, electronic hearing protectors are the perfect safety companion for indoor power tools (table saws, routers, etc.), outdoor power equipment (chain saws, trimmers, leaf blowers, etc.), and construction equipment (tractors, jack hammers, fastening guns, etc.).
Turn the switch on and adjust the volume at each ear until you hear sounds at their normal volume. If you increase the volume, hearing will be amplified. The LED will indicate that the circuit is on. The unit consists of a speaker in each ear pod, a control circuit, and a microphone and volume control for each ear. When any sound increases above 85 dB, the circuit recognizes the noise and stops transmission to the speakers before the sound reaches the ear. When the sound level falls below the 85 dB, normal hearing is restored.
This model has 2 microphones and offers stereo reception and functions in a manner similar to your ears so that you can better recognize the origin of a sound.
These hearing protectors have been tested to protect at an NRR of 20-23. However, this level of protection is based upon standardized test fixtures in the laboratory without the intervention of any extraneous conditions. In other words, the shape of a person’s head and/or how their hair is cut could permit sound incursion, which reduces the protection level. One of the most overlooked factors that reduces the effectiveness of any muff type hearing protection is eyeglasses. If you wear glasses your protection level could be compromised because the arms of the glasses prevent the ear cushions from making an efficient seal against the head.
In order to maximize the level of hearing protection available from any electronic muff style hearing protection, the best procedure is to first use foam ear plugs (these usually protect at a level of NRR 25 to 30) and then wear the electronic hearing protection (over the foam plugs) with the volume level turned high enough so you can still hear comfortably. What will happen when there is a loud noise is that the hearing protectors will default and protect at their passive level, and the foam ear plugs will protect at their NRR. This is an effective technique used by many people in sustained high noise level environments.