Mining has always been an arduous task, both underground and on the surface. NIOSH estimates that 80% of US miners go to work in an environment where the noise exceeds 85 decibels (dB), and that 25% of these are exposed to an environment that exceeds 90 dB. The major noise hazard in mining today is the pneumatic percussion drill. Impact from the drill bit, mechanical vibration from the drill casing and impulse noise from the exhaust generate the noise.

Miners Need Ear Protection!

Ancillary equipment from fans and blowers for ventilation is a considerable noise generator as well, and this noise is in the low frequency range. Additional low frequency noise comes from diesel powered load handlers and haulage equipment.

Low Frequency Noise

Low frequency noise is not easily eliminated with traditional passive hearing protection devices. Low frequency noise waves are long and carry great distances. They can penetrate passive barriers like foam earcups or even cement walls (which is why you can hear the bass of your neighbor's stereo).

Mining Noise Sources	dB Level
Cutting machines	83–93
Locomotives (electrical)	85–95
Haulage truck	90–100
Loaders	95–100
Long-wall shearers	96–101
Chain conveyors	97–100
Continuous miners	97–103
Loader-dumper	97–102
Fans	90–110
Pneumatic percussion tools	114–120