Core Drilling

Task
Using a pneumatic drill to make multiple holes in a concrete structure

Problem
Construction and repair tasks in concrete retaining walls, foundations, and dams often require holding and controlling a heavy vibrating tool for prolonged periods of time. Risk factors include high force grips, exposure to hand-arm vibration, and awkward postures of the back and upper extremities. Using a personnel lift does not eliminate these risk factors.

Intervention
A tool support was assembled from easily available lumber and secured to the guardrails of the lift with C-clamps. A guide for the bit was fabricated from steel pipe welded to a bracket that could be easily attached to the rails of the lift.

An in-line remote actuator was installed so that the worker would not have to bend forward to operate the trigger.

Cost
$100 in parts

Evaluation of Intervention

  • Pros
  • Significant improvement in back, wrist and shoulder posture
  • Virtually eliminates prolonged grip of tool and hand-arm vibration exposure.
  • Productivity significantly increased for large jobs.
  • Easy to assemble, can be used on rented lift equipment
  • Cons
  • Some areas inaccessible to the personnel lift.
  • Workers have to disassemble and reassemble tool support and bit guide for each job.
  • Some exposure to whole-body vibration remains.

Semi-Quantitative Evaluation of Intervention

  • Reduction of Identified Risk Factor
  • No New Risk Factors Introduced
  • Productivity not Reduced
  • Low Cost
  • Total
  • 5/5
  • 4/5
  • 5/5
  • 3/5
  • 19/20

Other Possible Interventions

  • Mount tool on articulating overhead support or "machine gun" mount.

Acknowledgements

Submitted by Ira Janowitz, PT, CPE, UC Ergonomics Program