New safety precautions have been put in place for a type of high-voltage switch involved in a fatal shopping centre explosion in Perth.
An electrician, 30-year-old Irish national Alan Cummins, was instantly killed in the blast on February 3 at the Morley Galleria shopping centre.
One of his workmates, 22-year-old Matthew Hutchins, died hours later in hospital after suffering burns to 80 per cent of his body.
Two of their colleagues were also seriously burnt but survived.
The four workers were carrying out maintenance near an electrical transformer when the explosion occurred.
On Friday, Energy Safety revealed the blast was caused by high voltage oil-insulated combined-fuse switches, produced by Long and Crawford Manchester.
The regulator has ordered the switches must be fully disconnected from the electricity supply before anyone opens the switch's lid.
"The type of switch involved allows the three fuses to be changed while the in-coming electricity supply at the base of the tank remains energised," director Ken Bowron said.
"It is unsafe to perform work on any item of electrical equipment while it remains energised, especially high-voltage equipment."
Mr Bowron said many similar Long and Crawford switches, of unknown number and location, were used by private owners.
"The order will be sent to all licensed electrical contractors in WA and property owners likely to have these switches on their property," Mr Bowron said.
The Electrical Trades Union said the order did not go far enough and should extend to all electrical equipment.
"We support the Energy Safety order relating to the high voltage equipment involved in this fatality," branch secretary Les McLaughlan said.
"However, we believe Energy Safety should be directing electrical contractors and property owners to not perform electrical work in any live electrical environment, rather than limiting their order to the piece of equipment involved in this incident."
