Case study on vibration health risk and comfort levels in loading crane trucks.

According to a survey published by the Brazilian National Transportation Confederation, recently, the Brazilian truck fleet has been increasing about 84.3%, accounting to, in 2016, a total value of 2 684 227 vehicles. Despite this growth, the quality of the road network did not increase proportionally to the necessary infrastructure for agricultural production flow. This work aims to infer, by the analysis of occupational exposure, the vibration levels acting on truck drivers, analyzing the vibrational degree for health risk and comfort levels. The whole-body vibration (WBV) in trucks of different models and capacities, at some speeds and pavement types, are evaluated using a portable vibration analyzer with triaxial accelerometers. The daily exposure to vibration A(8) is evaluated and compared with the occupational exposure limits defined by a National Regulation Standard, with measurement procedures defined by an Occupational Hygiene Standard, and level requirements defined by an International ISO Standard. It is concluded that the degree of comfort is higher for heavier vehicles with large wheelbase. Relative to the health risk conditions, the study arrives at the same conclusion; the degree of risk increases as the vehicle' speed and pavement's longitudinal irregularity increase. Regarding human exposure to vibration, the vehicles in their actual working situations presented a vibration scenario where the exposure limits are exceeded, resulting in unhealthy working conditions.