The Pacific Northwest Agricultural Safety and Health
Center conducts research and promotes best health and safety practices for Northwest workers and producers in
Maria Tchong-French
Blood (MS, Exposure Sciences, 2007) evaluated the ability of different seats to attenuate vibration exposures. Current engineering approaches to reduce a driver’s exposure to WBV rely on passive suspension systems, explained Johnson. These passive seat suspensions typically use compressed air or mechanical springs to reduce the WBV drivers experience. However, these technologies are slow to react to abrupt road changes and sometimes amplify rather than reduce vibration exposures, said Johnson. Recently, the Bose Corporation developed vibrationcanceling seats that employ a computer-controlled linear electromagnetic motor in the seat suspension to actively counteract and reduce vibration. In 2010, with funding from the National Institute for Occupational Safety and Health and from the department’s appropriation from the MA/AF, a research group led by Johnson teamed up with scientists at Harvard University to evaluate WBV exposures of drivers using the Bose seat. The University of Washington (UW) group included Blood, who is now a doctoral student (Environmental and Occupational Hygiene), Postdoctoral Researcher Charlotte Lewis, and Visiting Research Scientist Patrik Rynell. The study compared differences in WBV exposures among 16 drivers who drove one semi-truck outfitted with a new passive air-suspension seat and an identical semi-truck outfitted with the active vibrationcancelling seat along the same 60-kilometer route. Johnson said the seats developed by Bose reduced WBV exposures by up to 50 percent compared to conventional air-suspension seats that are standard equipment in most large trucks. The UW/Harvard team hopes to conduct a large randomized controlled trial to determine whether the active vibrationcancelling seat is a viable intervention for reducing WBV exposures and improving the low-back health of long-haul truck drivers. The UW research team will continue to evaluate the ability of seat suspension designs to reduce WBV exposures and ultimately low-back injuries among King County Metro bus drivers.
on the horizon...
Orchard Safety Professor Richard Fenske, Associate Professor Peter Johnson, and Research Industrial Hygienists Kit Galvin and Maria Tchong-French are working closely with tree fruit growers to ensure the ergonomic safety of workers as the industry adopts new technologies. Tree fruit production is the economic backbone of many Washington state communities. To make the industry more sustainable, orchards are transitioning from work done on ladders to work on mobile, raised platforms. By semiautomating labor-intensive aspects of fruit orchard work, including harvesting, pruning, and fruit thinning, orchards can increase efficiency and productivity and also reduce falls associated with ladders, the number one cause of injuries. Orchard-related injuries and illnesses take a huge toll on families and cost the industry and our state $8 million each year. Researchers will evaluate a new mobile platform (see photo above) because the equipment requires workers to lean and reach in new ways. “We’d like to get the right design now rather than years down the road,” said Jim Doornink, an orchard owner and member of the Washington Tree Fruit Research Commission. This research is supported by the National Institute for Occupational Safety and Health and through the department from the Medical Aid and Accident Fund.
farming, fishing, and forestry. http://depts.washington.edu/pnash/ 2009–2011 Biennial Report
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