The OSHA Noise Standard (29CFR1910.95) states when the 8-hour noise  exposure exceeds 90 dB-A, an effort to control noise through engineering  methods must be attempted.   Hearing protection alone is not an acceptable means of OSHA  compliance to the noise standard. The reason is simple, the poorest  means of protection, whether to noise or other health hazard, is to  utilize personal protection (in this case, hearing plugs or muff). The  best protection is to eliminate the excessive noise or isolate the  individual from the noise source. That means some form of engineering  control—design changes to the source or separation of a worker from the  machine.   There are a vast assortment of possibilities depending upon the noise  source and the amount of energy (in the form of noise) that is  produced. Remember that noise is energy and multiple sources compound  the energy produced. For example: two (2) machines side-by-side each  producing noise of 88 decibels each when combined that is...
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