The frequency and amplitude characteristics of vibration experienced at the feet under typical mining equipment operation were documented in this study. Foottransmitted vibration (FTV) was measured using a tri-axial accelerometer mounted at the location where the worker stood. A musculoskeletal disorder questionnaire, work history and demographic information were also collected. Vibration from locomotives (primary source exposure) had a dominant frequency below 6.3 Hz; whereas, drilling and raise platforms (secondary source exposures) were predominantly in the 31.5 to 40 Hz range. All workers reported lower limb discomfort and two had been diagnosed with vibration induced white feet. All raise platforms exposed the workers to vibration levels that placed them above the ISO 2631-1 health guidance caution zone for an 8- hour exposure. Further investigation using both ISO 2631-1 and ISO 5341-1 standards is needed to determine long-term health effects to the whole-body and feet of workers exposed to FTV.
Keywords:
Standing vibration, mining, foot-transmitted-vibration, white-feet, Raynaud’s phenomenon, ISO-2631-1