On the job

Friday, October 18, 2013
Police officer sitting in his parked car with the door open

Police officers spend up to four hours during a 12-hour shift engaged in computer and data entry in their cruisers. Wedged between the steering wheel and a restricted seat position because of a safety barrier, their laptop computers are mounted off to the side, which necessitates a twisted body position for computer access.

Adding to this discomfort, police officers always wear heavy duty belts – even for in-vehicle police work – that can hold up to 15 pounds of equipment.

The concern about the impact of these conditions on musculoskeletal pain and injury among police officers prompted the Municipal Health and Safety Association of Ontario to request assistance from professor Jack Callaghan–Canada Research Chair in Spine Biomechanics and Injury Prevention, professor Clark Dickerson, and graduate student Colin McKinnon: researchers in the Centre of Research Expertise for the Prevention of Musculoskeletal Disorders (CRE-MSD).

Their investigation began with a questionnaire to officers that confirmed high levels of discomfort in the lower back region. Using video cameras in cruisers, the researchers identified that over a 12-hour shift, computer use was the most frequent in-vehicle, non-driving activity. A follow-up laboratory simulation of driving a police cruiser and interacting with a computer showed that moving the laptop around within the constraints of current cruiser interiors did not alleviate the problem.

Clearly, alternate technologies and interface approaches were required to address the musculoskeletal disorders (MSDs) associated with the demands of the job.

The research team worked with an industrial partner on the design and testing of a car seat, which included an active lumbar support that periodically changes shape, a shortened seat pan, and additional structural modifications to provide both torso support and accommodate the police duty belt. During both simulated driving and actual cruiser operation, the new seat successfully reduced discomfort in the low back compared to the standard seat.

This project highlights the impact of CRE-MSD in bridging the gap between researchers and users – the workplaces and the occupational health and safety system. “We put into practice the Centre’s tagline: “Research Meeting Practice to Prevent MSDs,” explains Callaghan. “We bring researchers to the workplace to identify the key questions, research the best answers, and pass on the best knowledge that will lead to the prevention of musculoskeletal disorders at work.”