Farm machinery can expose operators to several hazards. Whole-body vibration (WBV) is known to be associated with back and hip disorders, but can also contribute to the risk of falls and collisions (‘accidents’). The years 1990 - 2008 averaged 104 Canadian farm fatalities/year and over 70% were related to agricultural machinery; during that period there were 38 fatalities specifically due to falls from agricultural machines. Driving itself also presents a health and safety risk. Between 2003 and 2007, 19.5% of all road fatalities were a result of heavy vehicle collisions/loss-of-control events, and a vast majority of crashes were attributed to driver error. Both fall risk and collision risk may be negatively affected by vibration exposure. The short-term effects of WBV include cognitive impairment, stress, loss of balance, reduced proprioception, and decrements in sensory and motor response. These effects can increase the risk of either a fall (due to disturbance of balance and proprioception), and increase the risk of a collision (due to impaired cognition, perturbed position sense, or errors of judgment). WBV is a thus contributing factor to fatal and non-fatal occupational injury resulting from accidents and errors, including equipment and machine-related injuries, falls, and vehicle crashes.
While engineering solutions such as vibration-dampening seating and engine isolation can reduce the whole body vibration levels associated with back pain, they do not mitigate the effects of extended static sitting. It is also not clear whether the frequencies of vibration reduced by specialized seating is the same ranges of the vibration spectrum which affect cognition, balance, and proprioception. Vibration-dampening seating is also very expensive (approximately $6000 USD per seat), limiting its feasibility for many producers. Alternatively, procedural controls such as rest breaks can be applied immediately without a cash investment. Advice commonly given to workers who are seated for extended periods is to get up and move around periodically to reduce musculoskeletal effects. For example, the Canadian Centre for Occupational Health and Safety recommends standing up and moving for 5-10 minutes out of every hour. There is also evidence that specific neck, arm, and leg movements performed after vibration can reduce vibration-related decrements in balance and proprioception. It may be that an appropriately-designed ‘alternate activity break’ can reduce the combined effects of seating and vibration, thereby reducing the risk of back and hip pain, egress injuries, and operator-error-related collisions.
The objective of this project is to develop a procedural control in the form of an intervention program appropriate for delivery to farmers. This project will involve the use of efficacy trials in the CCHSA Ergonomics Lab (https://research-groups.usask.ca/ergolab/), usability trials and user focus groups with farmers, followed by field testing for effectiveness.
Aims of Project
In order to deliver a procedural control and implementation plan suitable for wide-scale use or evaluation, this project will:
- Assemble a stakeholder advisory group of producers and other knowledge-users to help direct the study.
- Conduct a series of lab-based experiments to identify rest break activities that are most effective in reducing performance decrements associated with seated whole-body vibration (such as that found in tractor operation).
- Assemble the most effective activities into a single rest break protocol and test using farm-realistic exposure durations.
For further information about this project, please contact Program Manager Nadia Smith at 306-966-1648 or by email at email@example.com
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2019 - 2020 Year 1 Update
Producers and farmworkers are exposed to whole-body vibration (WBV) on a regular basis when operating farm machinery. Whole-body vibration is the mechanical vibration that, when transmitted to the whole-body, poses risks to the health and safety of operators. Exposure to WBV is cumulative over time. The goal of this project is to develop an evidence-based protocol for interspersing agricultural machinery operation with rest breaks to maximize the health and performance of workers while minimizing interruption of work that is applicable across all machinery-related agricultural tasks.
In Year 1, Activity 5 developed and pilot-tested protocols for lab-based testing of rest break activities. The project team was able to collect data during lab-based experiments where 20 experienced farm machinery operators were exposed to different vibration and rest conditions. These early tests provide preliminary data for planning WBV interventions on farms and analyses will remain ongoing.
Using the unique set of equipment available at the Canadian Centre for Health and Safety in Agriculture’s Ergonomics Laboratory, vibration exposures programs based on real measurements made on-farm were developed so that a simulated tractor cab on top of a robotic vibration platform is able to produce realistic farm-type vibrations.
An additional investigation stream was added to Activity 5 to evaluate musculoskeletal effects of agricultural machinery operation using cadaveric mechanical testing and micro-computed tomographic (micro-CT) imaging to measure biomechanical damage at the vertebral end-plate. This additional study will extract vibration conditions from previously collected field studies to simulate agricultural machinery used in a controlled environment to simulate musculoskeletal damage related to low back pain in agricultural machinery users. Mechanical and image-based outcomes will be used to determine health effects, which will then be compared to current occupational vibration exposure standards. The mechanical testing and resulting damage will complement in-lab tests with human participants to help determine effective rest break timing related to musculoskeletal damage.
An informational bulletin was also produced under the CANFARMSAFE publication Take a Break from the Shake.