How do you calculate the noise reduction rate when using earplugs and earmuffs at the same time?

Lesky · Jan 18, 2014

How do you calculate the noise reduction rate when using earplugs and earmuffs at the same time?

If you have earplugs with a NRR of 33 dB and ear muffs with a NRR of 30 dB.

What would the correct total NRR be?

Please also explain your calculation

I tried googling this, but did not find any clear answer.

Thanks in advance!
/L

Markku · Jan 18, 2014

See my post here: https://www.tinnitustalk.com/thread...ir-cells-safe-—-discuss.745/page-2#post-17753

("However, the attenuation of the combination is not equal to the sum of the individual attenuation values (Berger, 1983), as illustrated in Figure 1. Note for example; at 1000 Hz the combination of a 26-dB plug and a 34-dB muff does not yield 60-dB overall, but rather about 41 dB. The principal reason is the bone-conduction (BC) limits to attenuation, which are also illustrated in Figure 1.")

Lesky · Jan 19, 2014

http://www.audiologyonline.com/articles/extra-protection-wearing-earmuffs-and-1218

"No empirical or theoretically derived equations are available that can predict the attenuation of an earplug and earmuff combination with sufficient accuracy to be useful"

What the hell?

CDNThailand · Mar 3, 2017

Lesky said: ↑

http://www.audiologyonline.com/articles/extra-protection-wearing-earmuffs-and-1218

"No empirical or theoretically derived equations are available that can predict the attenuation of an earplug and earmuff combination with sufficient accuracy to be useful"

What the hell?
Click to expand...

Markku is right, that website is wrong

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How do you calculate the noise reduction rate when using earplugs and earmuffs at the same time?

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How do you calculate the noise reduction rate when using earplugs and earmuffs at the same time?

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Lesky Member

Markku Founder Staff Podcast Patron Benefactor Hall of Fame Advocate

Lesky Member

CDNThailand Member

How to Calculate NRR (Noise Reduction Rating) of Hearing Protection?

I Have Noise-Induced Tinnitus — What Should I Do?

My Tinnitus Sounds Like It's Coming from the Location of Other External Noises...?!

Whooshing Noise in Right Ear in Response to Other Sounds: Is This Tinnitus?

Ca(2+)n You Feel the Noise?

Share This Page