Working in the mining industry poses several health risks, one of the most pervasive of which is noise and hearing damage. MSHA (Mine Safety and Health Administration) standards in regards to noise exposure have been in place for decades, yet organizations continue to operate without proper compliance. In this article, we’ll reiterate the current MSHA standards and talk on compliance methods available.

MSHA Noise Exposure Standards

There are three standards for noise exposure that MSHA provides guidelines for:

  • Noise Exposure “Action Level” – this is defined as an 8-hour time-weighted average (TWA) sound level of 85 dBA. If a miner’s exposure equals or exceeds the action level, it is required that they be enrolled in a hearing conservation program. In doing so, significant reduction of the occurrence and progression of hearing loss caused by noise will result. This action level replicates OSHA’s standards and applies to both general and mining industry.
  • “Permissible Exposure Level” – this is defined as a TWA of 90 dBA. No miner at any time should be exposed to sound levels exceeding 115 dBA (even with proper hearing protection). If during any work shift a miner is exposed to noise levels exceeding the PEL, it is required that they be enrolled in a hearing conservation program and all feasible engineering and administrative controls are used to reduce the noise exposure. Hearing protection must also be provided.
  • “Dual Hearing Protection Level” – this is defined as a TWA of 105 dBA. If noise exposure exceeds the DHPL during any work shift, providing and ensuring the concurrent use of both plug type and muff type hearing protectors is required. In addition, all actions required for noise exposures that exceed the PEL should also be implemented.

Noise Exposure Compliance Options for Mining

Two steps can be taken in order to be in compliance with MSHA requirements.

  • Engineering Noise Controls: These controls involve reducing the sound levels from equipment or processes used that directly reach the worker. In other words, isolate the noise from the worker. An example of this is sound barriers, which reduces the sound level reaching the worker utilizing a physical barrier between the worker and the source.
  • Administrative Noise Controls: These controls involve limiting the worker’s exposure to the noise by removing the worker from the noise source (whether by distance, time, task efficiency, job rotation, etc.). In other words, isolate the worker from the noise. An example of this is requiring a worker to spend time behind a sound barrier because it reduces the time of exposure to the sound level outside of the barrier.

While one, the other, or a combination of both can be used to protect miners, the bottom line remains that it is critical to control the exposure of hazardous noise. O’Neill Engineered Systems, Inc. has a team of professionals that can evaluate, identify and recommend solutions that will protect your workers long-term. For more information, give us a call at (262) 367-6700 or contact us directly.