Electrical sub-board installation is common during construction. Electrical work needs to be performed by qualified and registered people. Appropriate guarding must be in place to prevent other people from making contact with or accessing live parts in sub-boards.
Summary of incident
A worker received an electric shock and suffered burnt fingers when he came in contact with exposed live buzz bars in a sub-board.
The sub-board did not have enough pole fillers to cover all live points in the board. The power was not isolated and the door to the live sub-board was left open. A worker in the vicinity, in answering a mobile phone call, lost concentration and inadvertently leant against the live sub-board, sustaining the electric shock injury.
Background
Electrical sub-board installation is common during construction. Electrical work needs to be performed by qualified and registered people. Appropriate guarding must be in place to prevent other people from making contact with or accessing live parts in sub-boards.
Probable causes
- The sub-board had exposed live parts due to insufficient pole fillers.
- The door of the live sub-board was left open when unattended.
- Distraction (from the mobile phone call) while working near the exposed live parts increased the risk of electric shock injury through inadvertent contact.
Action required
- Ensure that all live parts in sub-boards are fully protected by pole fillers.
- The door of the live sub-board must be shut prior to turning on power, unless testing is being performed.
- A person must move a safe distance away from potential hazards when performing unrelated tasks (like answering a mobile phone call), thereby minimising the risk of inadvertent exposure.
Above: An electrical sub-board with insufficient pole fillers.
Inset and below: Exposed live buzz bars in an electrical sub-board.
