The effect of spiked boots on logger safety, productivity and workload

The effect of a slack-pulling device in reducing operator physiological workload during log winching operations

The authors conducted a comparative test to determine whether the introduction of a hydraulic slack puller allowed reducing the physiological workload of operators assigned to log winching tasks. The tests were conducted in northern Italy, on the mountains near Como. The study involved five volunteer subjects, considered representatives of the regional logging workforce. Physiological workload was determined by measuring the operators' heart rate upon completion of specific tasks. The slack puller improved the efficiency of downhill winching, since it allowed a single operator to pull out the cable on his own, without requiring the assistance of a colleague. However, introduction of the slack puller did not result in any reductions of operator physiological workload. The main stressor when working on a steep slope is moving up and down the slope: pulling a cable is only a secondary stressor. Any measures targeting secondary stressors are unlikely to produce dramatic reductions of operator workload.

Os limites da abordagem clássica dos acidentes de trabalho: o caso do setor extrativista vegetal em Minas Gerais

Este estudo, baseado na literatura e no estudo de caso que será apresentado, discute as análises clássicas dos acidentes de trabalho, tendo como foco o setor extrativista vegetal, o qual vem registrando elevadas taxas de mortalidade de trabalhadores em todo o mundo. O estudo articulou duas técnicas: pesquisa documental e observações de campo. Os documentos analisados estavam disponíveis em Comissão Parlamentar de Inquérito. Foram observados os trabalhadores organizados em equipes para cortar as árvores de uma empresa do setor foco. Estudou-se o processo de trabalho por meio de técnicas de observação direta dos trabalhadores. Viu-se predominar nos relatórios técnicos consultados a ideologia do ato inseguro como causa dos acidentes analisados. No entanto, as observações do trabalho evidenciaram determinantes externos dos riscos ocupacionais. Foi possível, ao final, identificar modos operatórios de proteção contra os riscos implementados pelos próprios operadores. Os resultados indicam alguns limites das análises clássicas que não consideram o desenvolvimento da tarefa nas zonas de risco, sendo fonte de idéias preconceituosas sobre o comportamento inseguro dos operadores.

Understanding felling safety in the New Zealand forest industry

Highest injury rates within the New Zealand forest sector are reported for the logging operation, with up to 30% of logging injuries occurring during the felling task. This paper reports findings from a detailed task and job safety analysis of the motor-manual (chainsaw) felling task, and an analysis of New Zealand Accident Reporting Scheme data for logging injuries for the five-year period, 1996-2000. Key safety factors, including physical hazards and potential errors and violations associated with the felling task, were determined from the task and job safety analysis, along with possible adverse consequences and potential solutions for reducing injury risk. The potential for injury among inexperienced fellers was noted, as felling safety was dependent upon appropriate assessment of hazards and good judgement in respect of decisions regarding the felling of trees. The analysis of some 351 reported felling injury cases allowed identification of high-risk task elements, common injury initiating events and temporal and logger population injury patterns. Findings from the two methods of analysis were triangulated where possible to produce a better understanding of key risk areas. The potential risk associated with inexperienced employees, who incurred a high proportion of felling injuries, and the need for good judgement and decision making for different aspects of the felling task were particularly noted.

The role of the New Zealand forest industry injury surveillance system in a strategic ergonomics, safety and health research programme

Forestry is among the most hazardous of all industry sectors internationally. In New Zealand, highest work-related morbidity and mortality incidence rates are found in the logging sector. The New Zealand Forest Industry Accident Reporting Scheme (ARS) is a forestry injury surveillance system maintained by the Centre for Human Factors and Ergonomics (COHFE). The paper highlights the pivotal role of an industry-wide injury surveillance system in an industry-specific strategic research programme, giving examples of the use of ARS data in identification of priority areas for ergonomics, safety and health research attention, for safety awareness feedback to the industry, and in the evaluation of injury countermeasures. An analysis of injury patterns and trends for one high-risk forestry operation (skid work) is presented to illustrate both the capabilities and limitations of the ARS in its present stage of development.

Heart rate strain in cable hauler choker setters in New Zealand logging operations

This study examined the physical strain experienced by cable hauler choker setters, and the applicability of heart rate indices for measuring physical strain in commercial forest harvesting operations in New Zealand. The heart rate of four choker setters were recorded continuously throughout the working day and applied to heart rate indices. Based on the relative heart rate at work (%HRR), ratio of working heart rate to resting heart rate and 50% level indices, the mean working heart rate (HRw) of 106 bt. min(-1) +/- 6.9 (mean +/- SD) placed choker setting in the moderate workload category. The specific tasks of line shifts (120.3 +/- 4.8 bt. min(-1)), hooking up drags (118.8 +/- 6.6 bt. min(-1)) and uphill travel (126.1 +/- 12.9 bt. min(-1)), imposed the most severe workloads on the choker setters. This research also demonstrated that heart rate indices could be used as an effective means of determining the physiological strain of subjects working in New Zealand's commercial forest harvesting operations.

Testing the relative conspicuity of safety garments for New Zealand forestry workers

The relative conspicuities of six test garments (fluorescent orange, green/red, high-contrast, fluorescent lime-yellow, white, black) were assessed to guide the selection process of a standard upper body safety garment to be used within the New Zealand logging industry. Six male and four female participants, aged between 18 and 26 years, volunteered to perform 10 trials each on a demanding, central (tracking) task, while peripherally searching colour slides for test garments displayed on each of eight positions, against a pine forest background typically found in the New Zealand forestry. During each trial, transparency luminance was first gradually increased from darkness to daylight and then decreased to darkness again within 180 s. A head mounted ASL eye tracking system (4000SU) recorded the eye line of gaze for each participant, enabling a rank order of detection to be obtained for the tested garments in each trial. The fluorescent lime-yellow, fluorescent orange and white test garments were detected earlier than any other test garments across all trials, and the fluorescent lime-yellow test garment was detected first with a higher frequency than the white test garment. It was concluded that while white may be the most visible colour in near darkness conditions, as it provides highest contrast, fluorescent lime-yellow stands out better in twilight and daylight conditions against the pine forest background. The results of this study led to the promotion of fluorescent lime-yellow as the standard safety colour used in upper body garments within the New Zealand forest industry.