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Measurement of the Hand Transmitted Vibration of the Human Hand Arm System During Operation of a Hand Tractor
Published on: June 16, 2021
Forces required to operate controls on farm tractors: implications for young operators
F A Fathallah1, J H Chang, R L Berg
1Agricultural Ergonomics Research Center, Department of Biological and Agricultural Engineering, University of California, Davis, CA, USA. fathallah@ucdavis.edu
Ergonomics
|June 24, 2008
Summary
Farm tractor controls require significant force, often exceeding the physical capabilities of adolescents aged 13-17. This study highlights a potential safety mismatch for young agricultural workers operating farm machinery.
Area of Science:
- Occupational Health
- Agricultural Safety
- Human Factors Engineering
Background:
- Farm tractors are a leading cause of fatal injuries to adolescents in agriculture.
- A critical question is whether these injuries stem from adolescents operating machinery beyond their physical capacity.
Purpose of the Study:
- To quantify the forces needed to operate controls on common US farm tractors.
- To compare these forces with the estimated physical strength of adolescents and ergonomic guidelines.
Main Methods:
- Measured activation forces for steering, brakes, and clutch on 40 different tractor models.
- Compared measured forces against established physical strength data for teenagers and ergonomic limits.
Main Results:
- Tractor control activation forces frequently surpassed the physical abilities of most 13-17 year olds.
- A significant mismatch exists between adolescent strength and tractor operating forces.
Conclusions:
- Current farm tractors may pose a safety risk to adolescent operators due to high control forces.
- Findings support an ergonomic evaluation framework for assessing risks when young people operate machinery.
- Results can inform occupational safety policies regarding adolescent tractor operation.
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