Water Company Valves

Task
Large valve must be opened approximately once per day.

Problem
Manual operation of the valve requires repetitive, forceful gripping for10-15 minutes while turning the hand wheel. Risk factors include high force, high repetition, and awkward postures of the trunk and wrists. Initially, workers began using a valve wrench that decreased the force but made the upper extremity activity more repetitious.

Intervention
An electric valve operator was used, but it required prolonged trunk flexion and gripping of the motor until support brackets were fabricated and installed. These allowed the worker to rest the valve operator in the brackets and assume a neutral posture while the electric motor was doing the work.

Cost
$1000 for a electric valve operator and $100 in parts for brackets

Evaluation of Intervention

  • Pros
  • Repetitive gripping of hand-wheel eliminated
  • Prolonged trunk flexion and gripping of valve operator eliminated
  • Cons
  • Cost of vale operator and bracketsd

Semi-Quantitative Evaluation of Intervention

  • Reduction of Identified Risk Factor
  • No New Risk Factors Introduced
  • Productivity not Reduced
  • Low Cost
  • Total
  • 5/5
  • 5/5
  • 5/5
  • 3/5
  • 18/20

Acknowledgements
Submitted by Ira Janowitz, UC Ergonomics Program