Lifting Handles (Tools) for Plant Nurseries

Task
Lifting, carrying, and lowering potted plants to reposition them within fields or prepare them for shipping.

Problem
Workers in large commercial nurseries often need to "space" potted plants farther apart as they mature, and load them onto trailers or small trucks to bring them to staging areas for shipping. Pots are usually grasped with a pinch grip on the edge, with loads averaging 22 - 27 lbs (10-12 kg) in each hand. Ergonomics risk factors include repetitive flexion of the trunk, high force pinch grips, and sustained contact stresses on the hands.

Intervention
Handles were developed to grasp the edge of the pots, and provide a comfortable grip for the worker. The handles are height-adjustable to the preference of the individual user. The grip is designed to keep the wrist in neutral during the carrying phase, and for handling near ground level. If used for higher trailers or trucks, awkward postures of the upper extremities are likely to result. The handles work best for larger (eg., 2.5 - 5 gallon) pots, and for those made of firmer materials.

Cost
Estimated US $15.

Quantitative Evaluation of Intervention

Ergonomic Measure Without Handles With Handles
NIOSH Lifting Index
5.2
3.3
Forward Bending (% of job cycle)
22%
11%
Energy Expenditure (estimated % of aerobic capacity)
50.3%
50%
Grip Capacity (% of maximum)
25%
12%

 

Evaluation of Intervention

  • Pros
  • Pinch grip is eliminated in favor of power grip
  • Trunk flexion significantly reduced as a percent of job cycle
  • Contact stress on hands significantly reduced
  • Study showed pain symptoms reported by workers were significantly reduced
  • Cons
  • Handles will not work well with smaller (eg., 1 gallon) pots, or those made of softer materials
  • Handles need to be modified for placing pots on higher (eg. >14") trailers or truck beds

Semi-Quantitative Evaluation of Intervention

  • Reduction of Identified Risk Factor
  • No New Risk Factors Introduced
  • Productivity not Reduced
  • Low Cost
  • Total
  • 4/5
  • 5/5
  • 4/5
  • 4/5
  • 17/20

Other Possible Interventions

  • Change system of plant handling to allow palletizing so that fork lifts can be used.
  • Change trailer design so that bed of trailer can be lowered to more advantageous working height.

Acknowledgements
This project was funded by NIOSH and was carried out by the University of California Agricultural Ergonomics Research Center. Further information is available from the AERC website and in the CDC/NIOSH Publication, “Simple Solutions” [DHHS Publication No. 2001-111].