Incident Insights: Hazardous energy leads to a fan belt injury

On January 31, 2022, a UW employee was assigned to replace the motor-pulley V-belts on a supply air fan that was part of a multiple fan system. The maintenance worker turned off the electricity to the supply fan motor and removed the V-belt guard to gain better visibility of the belts. The fan stopped, but airflow from the other supply fans on the system caused the supply fan, under repair, to move in the reverse direction. The worker placed their gloved hand on the moving belts to stop the movement, and their hand was pulled into the belt and pulley system. As a result, the worker received lacerations on their hand and is receiving physical therapy to gain full use of their hand.

The root-cause of this incident was the source of hazardous energy created by the reverse movement of the fan energized by negative air pressure from the other fans on the system (called "windmilling"), which was not identified and isolated prior to starting work.

We are sharing this information to support our continuing effort to promote a culture of safety and to prevent future serious incidents. Please share this alert with anyone you think would benefit from this information.

For more information, please contact EH&S's Occupational Safety & Health Team at 206.543.7388 or [email protected].

Root-causes and contributing factors How to prevent future incidents develop a job hazard analysis energy control procedure identify all energy sources walk-down Complete the hazardous energy control procedure form prior to starting work Scope of work Affected personnel shutdown of equipment Type and magnitude of energy Energy-isolating devices (EIDs) releasing any stored or residual energy Record application verifying zero energy Record removing trained in LOTO and on the equipment annual audit and never place hands Report all accidents and near-miss incidents