Summary

The aim of this project was to identify the different vibration and sound sources from among a range of mining equipment which can potentially have a harmful effect on workers' health. First, a questionnaire was distributed to 12 underground mines to produce an inventory of the underground mining equipment. Eight (8) mines responded. A technical committee then established a list of categories of equipment to be evaluated by using a decision model taking into account the severity of the vibrations, the number of exposed workers, the average duration of the exposure, as well as data available in the literature.

Subsequently, a compact, robust and inexpensive acquisition system was developed so that a measurement campaign could be carried out in Québec underground mines. This system consists of two USB NI-9234 cards from National Instrument providing a total of 8 channels, an external Li-ion battery, a minicomputer with flash memory hard disk for extra reliability, as well as a small waterproof Pelican^tm case. To meet the requirements of ISO 8041:2005, an FIR digital filter was added to correct the gain in the low frequencies. Noise recording was done using a type 2 microphone connected to a digital recorder.

A total of 28 pieces of mining equipment in 8 Québec underground mines were evaluated. Several of these pieces of equipment have a sufficiently high vibration level to pose a risk over the long term to workers' health. The tasks associated with the highest whole body vibration levels are mucking with a backhoe (on rails and on wheels), the driving of some suspensionless vehicles, drilling on aluminum scaffolding, and the operation of scooptrams. The performance of the suspension seats of the different equipment was also evaluated. Several seats, mainly those of the Minecat 100PC and several scooptrams, contributed significantly to the increase in the operator's vibration exposure. The noise exposure of the operators of the different equipment was also documented. The pneumatic equipment, such as backhoes and pneumatic rock drills, had the highest noise levels.

Finally, seven specific recommendations were formulated for reducing mining workers' exposure to noise and vibration, based on the results obtained and the observations made during the measurement campaign.