How to protect your hearing
People wear earplugs for various reasons. Some of them desire to keep their ears safe from noises. Others want to prevent water from entering their ears during their swimming sessions, while some people desire to keep other things away by using ear plugs
Who wear ear protectors, Musicians, disc jockeys, scuba divers, Service personnel, aircraft maintenance staff, FI racing servicing personnel, heavy plant engineering operators, your neighbour. Do you wear ear plugs?
When to wear ear protectors
People differ in their sensitivity to noise. As a general rule, if you have to shout to communicate with a normally hearing person at a distance of about three feet, the noise is potentially harmful. Other signs to watch for are if the noise hurts your ears, causes your ears to ring, or causes temporary hearing loss for up to several hours after exposure. The start of unsafe levels begins at 85 decibels. It is not only the level of noise, but also the duration of exposure that determines whether it is a minor irritant, a definite disturbance, or a threat to your hearing.
What type of ear protectors
There’s a wide variety of types of hearing protectors available, including ear muffs, foam and preformed ear plugs, canal caps and active ear plugs. Selection is based upon several factors, as described below.
Ear Muffs - These devices fit against the head and enclose the entire external ears. The inside of the muff cup is lined with an acoustic foam which can reduce noise by as much as 15 to 30 decibels. Ear muffs are often used in conjunction with ear plugs to protect the employee from extremely load noises, usually at or above 105 decibels.
Ear Plugs - Preformed ear plugs come in different sizes to fit different sizes of ear canals. Formable or foam ear plugs, if placed in the ear correctly, will expand to fill the ear canal and seal against the walls. This allows foam ear plugs to fit ear canals of different sizes. Canal Caps - As the name implies, these devices cap off the ear canal at its opening. They generally provide less protection than ear muffs or plugs. These devices are not recommended for use by the EHSC
How to use ear protectors effectively
A good fit ; Correct Noise Reduction Rating & good maintenance.
What is NNR ?
The method to calculated the effective noise reduction of the ear protector.
For C-weighted measurements:
protected dB(A)=unprotected dB(C) – NRR
For example, if a protector has an NRR of 17 dB and it is used in an environmental noise level of 95 dB (c) , the noise level entering the ear could be expected to be 78 dB(A) [95 - 17=78] or lower in 98% of the cases if the protector is worn according to manufacturers specification.
For A-weighted measurements:
protected dB(A)=unprotected dB(A) - [ NRR - 7 ]
For example, if a protector has an NRR of 17 dB and it is used in an environmental noise level of 95 dB(A), the noise level entering the ear could be expected to be 85 dB(A) [95 - (17 - 7)=85] or less in 98% of the cases if the protector is worn according to manufacturers specification.