Mining Project: Noise Controls for Jumbo Drills Used in Metal/Nonmetal Mines
The objective of this project is to determine the primary noise generating components of common jumbo drill mechanisms and then develop engineering modifications that reduce noise emissions.
|Keywords||hearing loss, mining, noise control|
Jumbo drill operators in metal/nonmetal mines are exposed to high sound levels that frequently result in a hazardous noise dose and create an elevated risk of noise-induced hearing loss (NIHL). NIOSH OMSHR has made major advances in reducing NIHL in coal mine workers by developing multiple noise controls and other intervention tools. These noise controls have been incorporated into commercial products and have reduced the probability of NIHL by over 50%. This project seeks to bring equivalent NIHL reduction technologies to the metal/ nonmetal mining sector.
This project is proceeding in three phases:
- Noise source identification
The major noise sources in jumbo drills will be defined and ranked according to their contribution to worker noise exposure. Identification of the primary noise generating components and their locations will determine the types of noise treatments that can be applied most effectively.
- Engineering control development
Noise controls will incorporate a combination of computer modeling and machine prototyping. A jumbo drill machine manufacturer will be selected to collaborate with the project team to identify feasible acoustic and structural modifications. Computer simulation techniques will be used to determine the extent of noise reduction that will be obtained with each proposed modifications. Laboratory testing of prototype modifications will be performed to determine whether there is sufficient noise reduction and durability to implement the controls in a working jumbo drill.
- Laboratory and field testing
Once noise controls are developed they will be evaluated pre- and post-installation using sound power level measurements when possible, or a grid of sound pressure level measurements. If a noise control demonstrates a reduction above ground, it will then be installed on a working jumbo drill in an underground mine and tested for reductions in noise emission and worker exposure. A long-term collaboration with a mine will be established for the bulk of the testing, and two other mine sites will be developed for ancillary testing.