The Characteristics of Vibrotactile Perception Threshold among Shipyard Workers in a Tropical Environment

Abstract

The objectives of this study are to determine the prevalence of hand-arm vibration syndrome (haVS) and the characteristics of the vibrotactile perception threshold (VPT) among users of hand-held vibrating tools working in a tropical environment. a cross sectional study was done among 47 shipyard workers using instruments and a questionnaire to determine haVS related symptoms. The vibration acceleration magnitude was determined using a human Vibration Meter (Maestro). a P8 Pallesthesiometer (EMSon-MaT, Poland) was used to determine the VPT of index and little finger at frequencies of 31.5 Hz and 125 Hz. The mean reference threshold shift was determined from the reference threshold shift derived from the VPT value. The results show a moderate prevalence of haVS (49%) among the shipyard workers. They were exposed to the same high intensity level of haVS (mean = 4.19 ± 1.94 m/s 2 ) from the use of vibrating hand-held tools. The VPT values were found to be higher for both fingers and both frequencies (index, 31.5 Hz = 110.91 ± 7.36 dB, 125 Hz = 117.0 ± 10.25 dB; little, 31.5 Hz = 110.70 ± 6.75 dB, 125 Hz = 117.71 ± 10.25 dB) compared to the normal healthy population with a mean threshold shift of between 9.20 to 10.61 decibels. The frequency of 31.5 Hz had a higher percentage of positive mean reference threshold shift (index finger=93.6%, little finger=100%) compared to 125 Hz (index finger=85.1%, little finger=78.7%). in conclusion, the prevalence of haVS was lower than those working in a cold environment; however, all workers had a higher mean VPT value compared to the normal population with all those reported as having haVS showing a positive mean reference threshold shift of VPT value.

Dose–response relationship between hand-transmitted vibration and hand-arm vibration syndrome in a tropical environment

“…This is consistent with previous studies in tropical environments 2 15 16. We had expected the presence of dose–response relationship for finger coldness in this study, but it was not the case.…”

Prediction on Hand Arm Vibration Exposure Cause-Effect among Grass-Cutting Workers in Malaysia

“…The rationale of this study was established from occupational hand arm vibration knowledge for epidemiological methods used to identify and analyze the health cause-effects induce in a work related with vascular, neurological and musculoskeletal disorders at workplace. Hence, its principle method is to define a subjective and objective measures linked with the development of hand arm vibration syndrome (HAVS) which has a significant element for HTV in developing the health cause-effect of hand arm vibration exposure in Malaysia [9,10,11,12,13]. The investigation of hand arm vibration exposure to the health cause-effect associated to the HAVS is becoming a major interest for both human factor and occupational health in conducting their research study [11,12,13].…”

“…Hence, its principle method is to define a subjective and objective measures linked with the development of hand arm vibration syndrome (HAVS) which has a significant element for HTV in developing the health cause-effect of hand arm vibration exposure in Malaysia [9,10,11,12,13]. The investigation of hand arm vibration exposure to the health cause-effect associated to the HAVS is becoming a major interest for both human factor and occupational health in conducting their research study [11,12,13]. Statistics of occupational accidents by sector, which caused death, permanent disability and non-permanent disability, have been widely investigated and represented a significant problem to the Malaysian industries.…”

“…Hand arm vibration injuries begins with the workers exposing vibration transmitted energy to hand palm; hence experiencing discomfort or pain after operating hand-held vibrating equipment at a workplace [10,11,16,17,18]. Due to the magnitude, frequency and duration of HTV exposure at workplaces, the discomfort will lead to an increase of severity of symptoms and will experience hand pains and injuries [10,11,18]. The hand pains and injuries may eventually result in vascular, neurological and musculoskeletal disorders such as numbness, tingling, loss of finger sensation, or finger colour changes such as vibration induced white fingers [18,19,20].…”

“…In contrast to the other methods especially in determining the health causeeffect would be difficult because of the medical complication and cost increase [2,10,18,21]. Although there is established standard operating procedure to monitor the diagnosis of HTV exposure health cause-effect at workplace such as vibration magnitude and duration [22], observation [23], questionnaires interview [21] and vibrotactile perception threshold [11], a need to improve the risk control measure either by engineering or administrative of HTV exposure and to investigate the interactions between variables especially in Malaysia industry is still required [17]. Most of the investigations related to HAVS diseases are merely different from each country due to different climatic environment condition and work activities [24].…”