How Isolation Failures Harm People
The recurring patterns behind isolation incidents, and what each one tells you about where to put your effort.
11 min
Activities: 0 of 2
Work inside the machine
Maintenance puts people where normal operation never does: inside a guard, inside a vessel, between the rollers, on the wrong side of a valve. In that position, any unexpected movement, pressure or current reaches the person directly. Isolation is the control that keeps the energy away. When it fails, the result is often a crush injury, an amputation, a burn, a chemical release or an electric shock.
An intermediate practitioner must be able to look at a job and see where the isolation is most likely to fail. That starts with the patterns that repeat in incident reports.
Five recurring failure patterns
Match each event to its failure pattern
- A machine restarts from the control room during repair
- A hydraulic ram drops after the pump is isolated
- The neighbouring pump is locked by mistake
- The switch is off but nobody tested for voltage
A fitter presses an emergency stop button and reaches into a machine. Why is this not a safe isolation?