Simple precautions can reduce hearing loss

Extreme noise environments, like ambulances, are a known cause of inner ear damage and hearing loss. But, many people do not realize that, while hearing damage is permanent, it also is avoidable.

Studies show that stress from exposure to loud noise can cause and contribute to sleeplessness and hypertension. Police and firefighters should be aware of what they can do to reduce their risk now to ensure they can hear later.

A number of common sense measures can be taken by public safety personnel to ensure they do not damage their hearing while on the job. These include:

* avoidance of loud noise environments whenever possible — easier said than done. When off-duty, a point should be made to reduce excessive noise. During shifts, hearing protection should be worn around power tools (90dB), firearms (about 140dB) and other noise generators. OSHA requires employers to provide employees hearing protection at constant noise levels above 85dB;

* breaks away from the loud work area during a shift with exposure to continuous loud noise;

* use of hearing protection when working in an ambulance; and

* access to an audiologist for employees already experiencing hearing loss, however slight.

To reduce the extreme noise level of ambulances, manufacturers must meet standards defined by the National Truck Equipment Association, Farmington Hills, Mich. One mandate establishes the maximum sound level for ambulance compartment interiors at 80dB.

Additionally, the loudest siren must be under 123 dB, sirens must be mounted on the front of the vehicle to reduce occupants’ noise exposure and the frame must be insulated to absorb sound.

Use of hearing protection is also key. Worn correctly, ear plugs can be used to provide up to 30dB noise reduction. The downside of ear plugs is the consequent reduction in communications between personnel on board and with dispatch.

Headsets, on the other hand, provide hearing protection and allow for communication. A headset with a 24dB noise reduction rating (NRR) reduces ambient noise by that amount.

Headsets should include 24dB NRR, a noise-canceling microphone, voice activation (VOX) capability for “hands free” communication, an easily accessible “Push-To-Talk” button for radio transmissions and be lightweight and comfortable. Noise canceling microphones cut out the ambient noise so that speech comes through more clearly without background noise.

Headsets plug into and work with an intercom system, which interfaces with an existing radio. In an intercom, radio compatibility, modular components, ease of installation and, if applicable, multiple radio capability for tactical and command frequencies (including plugging the headset into a hand-held radio) are important.

Modular components plug in for easier installation and repair. Cables should be able to be replaced in five minutes or less. A digital message recorder to record incoming messages or commands is also useful.

Enhanced communication saves lives. Being able to hear incoming commands clearly can save critical seconds. High quality headsets and intercom systems are readily available to help enhance communications and increase safety for ambulance personnel.

This article was written by Judy Inmon for Firecom Corp., Portland, Ore.