Reference

Wearing earplugs and earmuffs together is the right call above about 100 dBA, but the protection does not add up. This guide explains dual hearing protection: when OSHA and NIOSH call for it, why combined NRR is not the sum of the two devices, how to apply the +5 dB rule, and how to combine plugs and muffs correctly.

A decibel levels chart turns noise numbers into a clear picture of when hearing damage starts and when protection becomes mandatory. This guide charts common tools and environments by dBA, lays out the OSHA 1910.95 permissible exposure limits hour by hour, and shows how to convert a noise level into the right earplug or earmuff NRR.