Whole- body vibration of heavy mobile equipment operators at an open cast mine.

Date
2017-12
Journal Title
Journal ISSN
Volume Title
Publisher
Stellenbosch : Stellenbosch University
Abstract
ENGLISH ABSTRACT: The measurement and analysis of whole-body vibration was done in accordance with ISO 2631-1 at a South African opencast mine to identify potentially unhealthy levels of vibration present in vehicles. Impulsive whole-body vibration was found on all measured vehicles and 90.6% of test cases showed possibly unhealthy levels of vibration exposure. The impulsiveness of the vibration led to the underestimation of the exposure by the RMS method. Bulldozer operators were exposed to the highest average levels of whole-body vibration. It is strongly advised that the use of high exposure vehicles are limited and that job rotation is implemented to limit the vibration exposure of these individuals. The vehicle tasks are used for as well as operating conditions were found to have a significant impact on whole-body vibration. A suitable measurement duration for different types of vehicles were statistically identified and it was found that measurement durations greater than 30 min and 60 min are sufficient to measure whole-body vibration with measurement errors of less than 25% (sufficient accuracy) and 12.5% (preferable accuracy) respectively.
AFRIKAANSE OPSOMMING: Die meet en analise van heel-liggaam vibrasie is in ooreenstemming met ISO 2631-1 by ’n Suid-Afrikaanse oopgroefmyn gedoen om moontlike ongesonde vlakke van vibrasie teenwoordig in voertuie te identifiseer. Impulsiewe heel-liggaam vibrasie was in alle voertuie teenwoordig en 90.6% van toetsgevalle het gedui op moontlike ongesonde vlakke van vibrasie blootstelling. Die impulsiwiteit van die vibrasie het gelei tot die onderskatting van die blootstelling vlakke deur die RMS-metode. Stootskraperoperateurs was aan die hoogste gemiddelde vlakke van heel-liggaam vibrasie blootgestel. Dit word sterk aanbeveel dat die gebruik van hoë blootstelling voertuie beperk word en dat werksrotasie geïmplementeer word om die vibrasie blootstelling van dié individue te beperk. Dit is bevind dat die taak waarvoor die voertuie gebruik word, sowel as die operasionele omstandighede, ’n noemenswaardige invloed op heel-liggaam vibrasie het. ’n Geskikte meettydperk vir verskillende tipes voertuie is statisties geïdentifiseer en dit is bevind dat meettydperke langer as 30 min en 60 min voldoende is om heel-liggaam vibrasie te meet met meetfoute kleiner as 25% (voldoende akkuraatheid) en 12.5% (gewenste akkuraatheid) onderskeidelik.
Description
Thesis (MEng)--Stellenbosch University, 2017.
Keywords
Vibration -- Measurement, UCTD, Opencast mine, Whole-body vibration, Automobiles -- Vibration Measurement
Citation