November 14, 2017

Learning Points: Demolition contractor electrical flashover

We have a UK Power Networks Learning points case study to share with you below.

The subject of the case study is "Demolition contractor electrical flashover" and it's applicable to persons involved in demolition activities. Here are the details:

A demolition contractor forced the door of a low voltage circuit breaker cubicle open using a metal crowbar. In doing so, the crowbar went across the terminals of the three phase service and caused a flashover that seriously burnt the individual and set the building on fire.

The factory on this site was redundant, but the 11,000 volt substation and low voltage service on site were live. No request to disconnect the substation and electricity service was made by the property owner when the factory closed down. Power was still being used on the site, but at a reduced level.

The demolition contractor had requested and had been provided a quotation to disconnect the substation and low voltage service, but had not accepted the terms of the contract or paid for the work to be undertaken. They were fully aware that the substation and services were "live."

The impact of this chain of events was the injured person received life-changing burns to his hands and face.

The demolition company who employed the injured person is under investigation by the HSE for breaches of health and safety legislation.

The learning points from this incident are as follows:
  • Never assume any electrical plant or cables on a site are dead unless proven so.
  • The CDM Regulations require utilities are disconnected prior to demolition commencing.
  • The Electricity at Work regulations require employers to adopt safe system of work to ensure electricity plant is safe before work commences on it.

No comments: