Earplug Noise Reduction Rating

Hi all,

A bit confused by ear plug ratings.

I have ear plugs which say 33db NRR. But then I look at the back and it has a list of frequencies and mean attenuation. None of these are 33db, they are all 38db +. Is the 33db the minimum attenuation or what?

If it's minimum 33db, surely going to gigs would be okay using them? They're HEAROS XTREME ones.

Say a gig averages 110db - 33db for ear plugs = 77db. I know there's the whole thing about bone conduction, but doesn't the skull provide 40db protection?

Thanks!

 

I think you just answered your own question. Leave it at that and put your earplugs in correctly and deep.