Innovative handles, clippers make nursery work easier

by T.J. Burnham, Special to Ag Alert

Its the age of ergonomics for California agriculutre, where power cutters and plant handles that avoid stooping have emerged as new tools for manual labor.

That's thanks to a four-year University of Califofrnia study in which Berkeley environmental health specialist Jim Meyers and others probed the stresses and strains of nursery labor and developed ways to make the job less injurious.

Now that they've developed some helpful tools in that segment of agriculture, they're moving on to the vineyard, said Meyers, where studies are already under way to probe the everyday aches and pains of the grape work force.

Just finishing up a $200,000-a-year study of the nursery industry for the National Institue for Occupational Safety & Health, which was funded for fours years, Meyers said the vineyard focus will be similar.

"We spent our first year defining jobs in four vineyards cooperating in the study," he said. "We talk with workers, finding out what they feel the high risks are in their jobs, and make an assessment of the injuries which have occurred at those jobs."

The nursery study, which was the first area investigated under the NIOSH program, was selected as a starting point to establish standards for examining other farm industries ergonomically, Meyers said.

"Nurseries were chosen because they feature a comparatively stable work force from year to year. It would be very difficult to conduct ongoing trials from year to year among workers who may not be on the job during the period of the study.

"Nursery workers also share many of the workplace characteristics of manufacturing industries in which prior ergonomic studies have been performed, and this helped us lay our plans for futher investigations in agriculture.

"Nurseries constiture a major sector of California agariculture, and share many workplace and work force characteristics with other farm commodities. This was our first time out of the box, and we wanted a representative and stable industry to begin with.

The NIOSH nursery probe, which will continue into 1998, revealed that the old problem of stoop labor was among the worst ergonomic offenders in the three named businesses studied.

"Repetitive cutting tasks and major lifting and carrying jobs which often meant moving awkward materials were also found to be big problems," Meyers said.

The study was conducted in an effort to isolate small work-related strains and steresses which, while they may only result in complaints while the workers experience them, can lead to major back injuries.

"We know there is a very high incidnce of back injuries in agriculture," Meyers said. "Sprain and strain are leading causes of overexertion which can lead to chronic back problems eventually."

In effect, what Meyers and the research team is doing isn't unlike the auto mechanics coping out the family car for signs of small disorders, which, unless fixed, can result in substantial breakdowns.

"Chronic injuries take years to develop," Meyers saidn, "but they show up early in terms of the strains and sprains people complain about." What is at work here, he explained, is CTD: cumulative trauma disorder.

"We felt if we could describe and prioritize the ergonomic risk factors and hazards for back injury and CTD in the nursery injury, we could begin to find ways to avoid haealth problems doen the road," he said.

The real value of the study, Meyers said, is that by analyxing such injuries, they can be addressed in terms of solutions.

Not only have improved handles and cuttrers been developed by UC agricultural engineers as a result of the study, he is investigating the potential of new research at Lawrence Livermore Laboratory on possible use of high-powered water streams or lasers to replace conventional repetitive motion agriucltual cutters, such as those used by nursery workers in bench grafting.

"Most of our small agricultural tools date back to the turn of the century," he said.
"Not much has changed since then."

But Meyers explains that the goal of the study isn't to develop automation which replaces human workers. "Displacing workers with high capital cost machines isn't always the best answer," he said.

The nursery study shows that two jobs, plant cutting and lifting and carrying, cause the most grief for workers in terms of health-related difficulties. "People making cuttings for propagation spend five days a week literally doing tens of thousands of cuts with a small pair of hand clippers. "There is clear evidence of carpul-tunnel injury as a reslut of closing hands that many times every day, year after year," he said.

The result of this study finding is an effort by UC Davis agricultural engineer John Miles to develop a power clipper, which he is also working on for vineyard workers.

Nursery workers' second greatest problem, lifting and carrying potted plants all day long, often engages laborers in 90-degree bodystoops, Meyers said. "Each time, they need to pinch the edge of the containers, a task that takes a lot of force to lift containers of two to three pounds, damaging the nerves and joints of their fingers in the process."

Lifting and carrying five-gallon containers, normally one in each hand, results in similar disorders, he discovered.

The solution of this problem, termed the "intervention" in scientific jargon, has been to develop handles that easily latch onto the container lips, resulting in less stooping and pinching. This invention, also a Miles tool, comes in many forms, with some designed to pick up three small cans, and other just for single five-gallon lifting.

"We have cut the distance the worker has to stoop in half," Meyers said, "and the pinch grip is totally gone."

While it will take years to determine whether injuries have lessened a result of using these tools, or if efficiency improves, Meyers' gut feeling is that they will. In fact, researchers have already seen what he called "slight improvements" in productivity.

"We have significantly fewer reports by workers of pain," he said. "That's really coming as no surprise."

The workers certainly like the new tools, often hiding them or taking them home to make sure the research handles are there for them the following work day, Meyers observed.

"We have been very successful in changing these jobs for the better," he said, noting that he feels similar improvements can be found for the vineyard and other agricultural jobs.

He is having a hard time finding a commercial manufacturer who wil mass produce the new handles, which are in the public domain, meaning UC would receive no payment by such companies making the tools.

Look for Meyers and other ergonomic reserachers on the agricultural job site in the future, making use of gizmos like the computerized Lumbar Motion Monitor buckled on workers' backs as an "external spine" to measure bending and twisting, and the Chatillon dynamometer to measure lifting force.

"After the vineyard, we want to go on in productive studies to prevent injuries in agriculture," said Meyers.

Agriculture should take a keen interest, since "ergonomic tools can make the human tool more productive," Meyers said.