BHP Mitsui Coal’s Poitrel mine, in Queensland, Australia, now holds the title of world’s largest blast using wireless technology after successfully completing the third blast in a trial series to test Orica’s WebGen technology.

The latest blast on October 13 saw 1.3 million cu.m of overburden shifted in a strata blast fired with 1920 WebGen 100 units across 534 holes, BHP Mitsui said.

Jayson Smeeton, Poitrel Mine Production Manager, said there were significant safety and efficiency improvements to be made by using the WebGen technology Orica is trialing, which features wireless in-hole primers initiated by a firing command that communicates through rock, water and air.

“Wireless blasting means we are able to really reduce our people’s exposure to dust in the pit, and eliminates the potential for misfires because they do not need to physically tie each hole in to the blast pattern,’’ Jayson said.

“Eliminating the need to tie in each hole also makes the process for loading explosives far more efficient, and less susceptible to wet weather delays, as the pit does not need to be shut down because of the potential risk of accidental ignition during thunderstorms.”

The first trials conducted in May and June were small shots to test the technology. The latest blast involved a more complicated strata blast, with the top and bottom decks of the shot fired at different times to maximise fragmentation, and preserve the coal below, according to the miner.

Further production blasts, including through-seam blasts are planned for the next 12 months, BHP Mitsui said.