Plugs PROPERLY inserted, coupled with muffs is the best protection, however it is not a sum of the two db reductions. Take the highest and add 10% or so.
Muffs add one advantage over plugs alone and that is protecting the outer area around the ear (mastoid) from vibrations that can cause hearing loss in the middle ear
From a Google search:
http://www.elvex.com/FAQ.htm
http://www.noisehelp.com/double-hearing-...
http://www.noisehelp.com/double-hearing-...
Muffs add one advantage over plugs alone and that is protecting the outer area around the ear (mastoid) from vibrations that can cause hearing loss in the middle ear
From a Google search:
Best Answer: NRR is a dB logarithmic scale and is NOT additive. Wearing two hearing protection devices that are close to equal will add about 3-6 db NRR, so in your case if you combine both, you get about 30NRR. Note that every 3 db of NRR reduces ambient sound by 1/2 the energy.
http://www.labsafety.com/refinfo/ezfacts...As a rule of thumb, an improvement of 5 dB (over the higher-rated one) is often assumed, for a combined NRR of 37 in my example, 32 in your case.
This 4 to 8 dB of additional protection translates into a 60% to 85% reduction in sound intensity, a marked reduction in the risk of hearing damage.
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Which One Is More Important, Ear plugs or Ear muffs?
Typically the ear plugs will have a higher NRR than the ear muffs, so they are the more critical component of a double protection system.
http://www.elvex.com/FAQ.htm
http://www.noisehelp.com/double-hearing-...
http://www.noisehelp.com/double-hearing-...