Hearing loss happens slowly so an individual may not notice until there is a serious decrease in the ability to hear normal sounds. Not only does this interfere with enjoying life, but it may be hazardous on the job. Excessive noise (noise is unwanted sound) doesn’t just hurt one’s hearing, but can cause tinnitus, a ringing sound in the ears; fatigue and nervousness or anxiety; elevated blood pressure; and increased stress that can help lead to heart disease.
Noise levels are measured in decibels (dBA). When we talk, the sound level is about 60 -65 decibels. Decibels are measured on a logarithmic scale, so when the decibels go up a little, the noise goes up a lot. An increase of just three dB doubles the sound energy, which is what damages your ears. Hearing protection is needed when the noise level is elevated; this is also determined by exposure time to that noise level. Very high levels for a short period of time can be just as harmful as lower noise levels that last for longer periods of time.
If you have to raise your voice for someone three feet away to hear you, the area may be too noisy and hearing protection may be necessary. Another sign of excessive noise exposure is when noises seem muffled at the end of the day. This effect usually goes away after a while, but if it keeps happening it will become permanent.
|Whisper||30||Tractor full throttle||100|
|Normal conversation||60||Chain saw||120|
|Vacuum cleaner||75||Military jet take-off||135|
|Inside new tractor cab||70-80||Siren at 100 ft.||140|
Noise levels change depending on how far away you are from the noise source. A noise that measures 100 dB at 10 ft. will measure 94 dB at 20 ft., and 82 dB at 80 ft.
Safety Training for Employers and Supervisors of Adolescent Farmworkers
Funding provided by National Institute for Occupational Safety and Health, grant no. 5 U50 0H008107-02
Publication #: 5 U50 0H008107-02
Disclaimer and Reproduction Information: Information in NASD does not represent NIOSH policy. Information included in NASD appears by permission of the author and/or copyright holder. More