Biological and Agricultural Engineering

Health and Safety Engineering

California agriculture suffers from an excess of on-the-job injury, with a rate of approximately 46 per 1,000 workers annually. Musculoskeletal injuries constitute well over 50% of this total. In addition, workers’compensation insurers and others report that this category of injury, which includes back injuries and cumulative trauma disorders, is both the most costly and the fastest growing. Recent efforts have also focused on injury prevention for children. In conjunction with the National Farm Medicine Center and the National Children’s Center for Rural and Agricultural Health and Safety, our department is involved in developing guidelines for parents to help them assess their child’s ability to safely complete common farm tasks.

Tools and systems for field workers are normally designed to promote productivity. Redesign of tools to enhance worker safety must not only address the productivity, quality, and cost issues imposed by management, but must also address a wide range of human factors in order to gain worker acceptance. In response to government concerns, our department is focusing a research program on agricultural ergonomics.The objectives of this program are to identify common agricultural ergonomic hazards; to describe ergonomic injuries related to agriculture; to design practical and effective prevention tools, equipment, workplace design, and work practices; and to demonstrate the results.

Research activity has focused on forestry, farms, nurseries, and vineyards. A system was developed to monitor guyline cable tensions, and thus assist in preventing yarder failures, which significantly contribute to the extremely high accident rate associated with forest operations. Ladder design and fruit collection procedures for citrus workers has received research attention since accident records indicate a high percentage of field injuries related to the ladder/picking bag environment. A major project with the nursery industry focuses on identification of ergonomic concerns and the development of refined tasks and tools that reduce potential hazards. Some of the new tools are now being produced commercially. Ergonomic hazards in wine grape vineyards are currently targeted for engineering interventions. At least four new harvest tools will be evaluated during the 1998 harvest.



The Lumbar Motion Monitor continuously records the bending and twisting of this nursery worker’s lower back. Data are transmitted by radio signal to a lap top computer for storage and eventual analysis.



Our department has a strong program in farm safety. Throughout the year, faculty and students provide demonstrations to farmers on new technologies and related safety concerns.

Tires for forestry vehicles provide the only cushioning for the vehicles, which travel over rough terrain. We are measuring the spring and damping characteristics of the tires so that accurate models of forestry vehicle dynamics can be developed. The models will be used to see what changes to the vehicles would be most effective at reducing vibration experienced by the vehicle operators.



Our primary goal in agricultural ergonomics research, is to enhance the working conditions of farm laborers. For these vineyard workers we continuously record lower back posture with a Lumbar Motion Monitor. The information gained will then be used for developing new hardware and procedures for workers’ daily tasks.



Vineyard workers exhibit awkward postures while picking wine grapes. Our current research focuses on new techniques and hardware that reduce body stress.



The agricultural ergonomics research team has developed handles to allow these workers to lift nursery pots off a trailer and then lower the pots to near ground level by allowing the handle to slip through their gloved hands.