Objective: Prolonged exposure to hand-transmitted vibration (HTV) is associated with an increased risk of hand-arm vibration syndrome (HAVS). This study aimed to identify the signs and symptoms associated with coal workers using hand-held vibrating tools in a northern China coal mine, and to determine the risk factors for HAVS.
Methods: A cross-sectional survey was conducted of 167 male workers with part-time exposure to HTV. A structured questionnaire was administered to the workers along with a series of function tests. The frequency-weighted vibration acceleration of hand-held tools was measured. The prevalence ratio and symptom correlation to HAVS among the different subgroups were evaluated.
Results: The prevalence of hand numbness, carpal tunnel syndrome, hand ache, tinnitus, memory loss, dizziness and headache showed significant differences in the longer-exposure groups (working years > 3 years or the daily-exposure duration > 2 h), compared with the control group (P < 0.05). Function tests showed abnormal findings only in vibration sensation and the X-ray examination of the longer-exposure groups (P < 0.05). The logistic regression analysis showed that longer working years, higher daily exposure and alcohol consumption were risk factors, while wearing anti-vibration gloves showed protective effects for hand numbness.
Conclusions: This study has identified the main signs and symptoms of HAVS among coal workers exposed to HTV in China. More information related to occupational safety and health programs are required to reduce the risk of HAVS.