Poor machine design encourages unsafe behaviour

Many of forestry’s hazards are due to the handling of large trees and large machinery in rough terrain and remote areas and these come with the job. Some hazards however, result from machine designs that are not compatible with the human form.

Swedish researchers Lars-Ola Bligård and Carola Häggström suggest that as well as the most common approaches to improving work safety, including reducing mechanical hazards or improving the safety culture, it is worth focusing on how the design of machines and workplaces directly influences human behaviour. 

The study, published in Australian Forestry, identified activities such as maintenance and repair work as especially hazardous in the highly mechanised cut-to-length forestry method. 

Previous studies have shown inadequate design is a common source of human error because it makes risky behaviour seem much faster and easier than the safe alternative. In these situations, the natural human behaviour is to use the less safe option.

In 2016, the University of the Sunshine Coast’s Dr Mohammad Ghaffariyan reported that 72 per cent of Australia’s forest-harvesting accidents during the decade to 2014 were due to human error – such as failure to use personal protection equipment, errors of operation and poor body positions. This suggests a change in human behaviour can have a significant impact. 

Highlighting the role of machine design in hazardous human behaviour may also counteract the development of a blame culture, where the causes of accidents are entirely attributed to human actions or behaviour. Bligård and Häggström suggest a blame culture is more likely to emerge if accident prevention work focuses solely on internal factors (such as education and training).

In their case study investigating hazards when changing a saw chain on a harvester, they applied a four-step evaluation framework based on Combined Cognitive and Physical Evaluation, a methodology developed for safety- critical applications, primarily medical technology. The conclusion of this particular case study was that operators could not physically perform their duties in a safer manner because the harvester had not been designed to fit human anthropometry. 

Bligård, L.O. & Häggström, C. (2019). The use of an analytical method to evaluate safety and ergonomics in maintenance of forest machinery. Australian Forestry, 82(1): 29-34.
Ghaffariyan M.R. (2016). Analysis of forestry work accidents in five Australian forest companies for the period 2004 to 2014. Journal of Forest Science, 62: 545–552