Mining Publication: Noise Controls for Vibrating Screen Mechanisms
Original creation date: January 2011
National Institute for Occupational Safety and Health (NIOSH) studies show that 43.5% of surveyed coal preparation plant workers had noise exposures exceeding the Mine Safety and Health Administration Permissible Exposure Level. Sound levels around vibrating screens in these plants often exceed 90 dB(A). NIOSH is currently developing noise controls for horizontal vibrating screens. To characterize noise sources, NIOSH researchers performed sound pressure level (SPL) measurements on a vibrating screen at their Pittsburgh Research Laboratory. The results show that the entire screen contributes to noise below 1 kHz and the vibration mechanism housings are most significant above 1 kHz. Constrained layer damping (CLD) treatments and an enclosure were used to reduce mechanism housing noise. These were evaluated using sound power level measurements according to ISO 3744. The CLD treatments reduced the A-weighted sound power level by 3.1 dB in the 1 to 10 kHz one-third-octave bands. A panel-on-frame vibration mechanism enclosure using various types of panels further reduced the A-weighted sound power level from the CLD configuration in the 1 to 10 kHz one-third-octave bands by 3.7, 4.0, and 3.9 dB for aluminum, steel, and Dynalam panels, respectively. The combination yielded a 7 dB reduction from baseline in A-weighted sound power for the same frequency range.
Authors: MJ Lowe, DS Yantek, HE Camargo, LA Alcorn
Peer Reviewed Journal Article - January 2011
NIOSHTIC2 Number: 20040455
Trans Soc Min Metal Explor TP-10-027, 2012 Jan; 330:446-451
See Also
- Analysis of a Mechanism Suspension to Reduce Noise from Horizontal Vibrating Screens
- Determination of Sound Exposures (DOSES): Software Manual and Implementation Guide
- Less Sound Underground: Reducing Roof Bolting Machine Drilling Noise
- Noise and Vibration Reduction of a Vibrating Screen
- A Noise Control for A Roof Bolting Machine: Collapsible Drill Steel Enclosure
- Practical Application of a Partial Cab to Reduce the A-Weighted Sound Level at the Operator's Station on Surface Drill Rigs
- Results of Noise Measurements from Underground Testing of a Roof Bolting Machine Duty Cycle
- Structural Vibration as a Noise Source on Vibrating Screens
- Technology News 536 - NIOSH Develops New Software to Analyze and Reduce Noise Exposure
- Water Well Safety Bits: Health And Safety Information For The Water Well Industry
- Content source: National Institute for Occupational Safety and Health, Mining Program