Vibration Exposure Analysis Among Two-Wheeler Riders in Kerala

Abstract

Two-wheelers are one of the most commonly used public transportation mode in Kerala. Two-wheeler riders are exposed to hand arm vibration (HAV) and whole-body vibration (WBV) during their riding due to varying road conditions. HAV exposure occurs when rider controls the vehicle and WBV occurs when driving through irregularities in the road. This study aims to quantify HAV and WBV exposures among two-wheeler riders during their travel on different road conditions and with different suspension types in the vehicle. It also attempts to explore the effect of pillion rider on these exposures. Qualitative risk assessment using modified Nordic questionnaire and odd ratio test was conducted to identify the severity of disorders felt by the riders. Quantitative vibration exposures are measured using accelerometers and an Arduino-based data acquisition system as per ISO guidelines. Exposure levels obtained from the experiment were assessed with standard limit values proposed by European directive 2002/44/EC standards. Results of qualitative risk assessment showed discomfort in upper extremities and lower back of the riders. WBV exposure is more severe compared to HAV in both types of suspension bikes and has exceeded the standard limit values. The result also revealed that the pillion rider presence can reduce WBV exposure on rider, whereas pillion rider doesn’t have any influence over HAV exposure. The presence of irregularities in road surface has significant influence on both WBV and HAV. Time duration in years required for producing hand arm vibration syndromes in dual shock bike users were found to be lower than the mono shock bike users. WBV exposure was found to be severe, which act as the causal factor for the discomfort felt in lower back and neck. However, HAV exposure doesn’t have influence over the pain felt in upper distal extremities. This can be attributed to other health hazards like repetitive strain injuries.