From The Ergoweb® Learning Center

Ergonomic Practices are no Sour Grapes

Researchers at California’s Agricultural Ergonomics Research Center (AERC) at UC Davis are hoping to make grape harvesting much more sweet than sour for California workers.

AERC is part of the Biological and Agricultural Engineering Department at the University of California. The mission, as stated by the center is, “to understand and apply ergonomic approaches to development and evaluation of equipment designs and work practices that prevent musculoskeletal disorders in
agricultural work.”

According to the AERC, the California Department of Industrial Relations shows almost half of all occupational injuries occurred in the agricultural production area. An analysis of ten years of injury data in California’s agriculture showed that 43% of all reported agricultural non-fatal disabling injuries were sprains and strains, of which 40% were back injuries.

While field jobs such as harvesting, weeding, and irrigating, remain demanding physical tasks, involving stooped postures, lifting and carrying, and repetitive hand work, research has shown that many important risk factors can be successfully addressed in agricultural work through using ergonomics principles.

Applying ergonomics principles to reduce or eliminate exposure to these risk factors is exactly what the Winegrape Harvest and Vineyard projects are accomplishing. These two projects have lead to the development of new harvesting bins, and machinery to move the bins reducing worker exposure to lifting, carrying, and bending. Both studies are funded by the National Institute of Occupational Safety and Health (NIOSH).

Ergoweb recently interviewed Dr. John A. Miles of the AERC to get more information about the ongoing projects:

EW:Thank you, Mr. Miles, for taking the time to answer some questions with regards to the current AERC Vineyard projects.

EW:1. I read that these projects are taking place in cooperation with some of the local wine producers. In general, have you found businesses in this area receptive to ergonomics and engineering
controls to reduce the exposure to MSD risk factors?

JM: Vineyard operators, and agricultural producers generally are interested in providing improved work environments for their workers. As an industry the managers and workers have a pretty good understanding of their hazardous environments. The problem we have found is that they lack
feasible alternatives. In the situations where we have been able to find or design interventions, acceptance has not been a problem. About two years ago we reported that an alternative picking bin very significantly
reduced the incidence of persistent pain among the workers picking grapes. This year we know of at least 2000 workers who are using this alternative.

EW:2. California recognizes that many low back injuries occur in agricultural work. Some of the AERC work focuses on risk factors like bending, stooping, lifting and twisting. Are other risk factors also
being studied here?

JM: We have done a limited amount of work with hand and shoulder problems, mostly related to use of shears in nursery propagation or tree and vine pruning. We developed an alternative powered shear for nursery work which is now in low volume commercial production with over one hundred units in the field. We have also done a bit of work on limiting exposure to vibration while working on moving machinery.

EW:3. What kind of success has the AERC seen to date in regards to vineyard work?

JM: Our initial surveys showed 62% of the manual grape picking workers experienced persistent pain by the middle of the picking season. This pain was distributed over many body parts, but about 50% of the workers complained about back pain. By changing bins and reducing the weight of an average bin from 57 lbs. to 46 lbs. we changed the number of workers with persistent pain to 25%. We did not believe the numbers, so we repeated the trial a second year, with almost identical results. The past two years we
have attempted to provide mechanical handling of the bins so that the workers did very little lifting or carrying. The results are not yet tabulated, but I think we are going to drop below 10% with persistent pain.

The alternative bin has already been widely adopted. The mechanical handling of the bins is not yet ready for commercialization, but I am hopeful that this will also become a standard practice.

EW: Is there anything else you would like to add for our readers on the subject of ergonomics?

JM: As an engineer, I tend to think about intervention design as the critical issue, but in fact the more social issues related to establishing relationships with workers, understanding their real problems, and involving them in the problem solutions are at least as important to the adoption of an intervention as the design itself.

EW: Thank you.