My engineers use, SDS drills, Angle Grinders, Impact Drills etc. Varying in use on a daily basis, specifically if installing electrical containment on projects on commerical and industrial sites.

From my understanding, if the noise level iis at 115dB's, whilst using a grinder to cut containment and they wear hearing protection which is at 30dB (SNR).

Then they wouldnt need health surviellence as this is reduced below the UAV?

Any help greatly appreciated.