Explosion at Tom nan Clach wind farm south of Nairn injures worker

What happened

A subcontractor working on the Tom nan Clach wind farm south of Nairn was injured when a power cabinet controlling 33,000 volts exploded. The worker had been carrying out maintenance on one of two cabinets at the site. An initial isolation switching programme had been changed twice, leading to confusion over which cabinet had been isolated. Power was restored to the wrong cabinet while work continued. A flashover occurred, engulfing the worker in flames. Colleagues used fire extinguishers and cold water until emergency services arrived. The worker was airlifted to a specialist burns unit and required multiple surgeries. Natural Power Services admitted health and safety breaches and was fined.

Contributing factors

The original isolation switching programme was not followed. Changes to the programme caused confusion over which cabinet was isolated. The cabinets were poorly labelled. Checks that the correct cabinets had been isolated were inadequate.

Lessons learned

1. Ensure isolation switching programmes are followed exactly and any changes are clearly communicated and documented.
2. Label all high-voltage cabinets clearly and unambiguously before maintenance begins.
3. Verify isolation of the correct equipment before work proceeds and before power is restored.

More lessons on electrical protection and isolation, maintenance, inspection and ageing assets, from every incident on the register.

Source

inverness-courier.co.uk