Understanding Hearing Loss
Hearing loss is a normal part of the aging process. Throughout our lives we are exposed to loud noises and physical conditions that add up to gradual loss of hearing. But many of us lose our hearing prematurely by failing to protect ourselves from excess noise both at home and at the workplace. Understanding how hearing works can help you realize the importance of protecting your hearing now, before it’s too late.
How Hearing Works
The ear is composed of numerous delicate structures designed to carry sound waves to the brain. The hair cells in the inner ear are particularly important because they stimulate the auditory nerve which transmits impulses to the brain. The brain translates auditory impulses into the sounds that we hear. When the ear’s hair cells become damaged due to excess noise exposure, the auditory nerve is not sufficiently stimulated, the brain does not receive the appropriate sound signal, and we fail to hear correctly. And, when hair cells are damaged by prolonged over-exposure to loud noise, they “die” and cannot be replaced, resulting in permanent hearing loss.
Excess Noise Exposure
Noise is measured in units called decibels (dBs or dBAs) Excess noise is generally considered to be exposure to 85-90 decibels or more over an 8-hour period. A typical automobile horn can be as loud as 120 decibels, but hearing a horn honk for 10 seconds is unlikely to cause hearing loss. If you had to listen to the horn blast for 8 hours straight, though, you could very well experience gradual, permanent loss of hearing. Or, if you work in a factory and are exposed to 80 decibels of noise over a 4-hour period, you might not be at risk. But, if you then went home and operated a power mower or tools, listened to high-volume music, or perhaps practiced at the shooting range, you could very well exceed your safe noise exposure limit.
Protecting Your Hearing
On or off the job, you can protect your hearing by wearing the appropriate personal protective equipment recommended for your tasks. Ear muffs, plugs, and canal caps can all reduce the amount of noise your ears are exposed to. It also helps to know the decibel range or noise level of some common activities and situations to see if you may be exposing yourself to too much noise. Remember that even loud vacuum cleaners, dishwashers, and home power tools can create excessive noise, so protect your hearing wherever you are.