The press of an emergency stop button could have prevented the deaths of four people at Australia's Dreamworld theme park, an inquest has heard.
Cindy Low, Kate Goodchild, her brother Luke Dorsett and his partner Roozi Araghi died after being thrown from a raft on the Thunder River Rapids Ride, following a operating system malfunction in October 2016.
Low's son and Goodchild's daughter, aged 10 and 12 respectively, were also on the raft, but survived the accident.
Detective Sergeant Nicola Brown told the Queensland court on Monday that a young female operator had access to an emergency stop button in the unload area, which could have stopped the ride's conveyer belt within two seconds, according to ABC News.
There was also a main control panel at different location which only had a "slow" stop button, taking about seven seconds to stop the ride.
A week before the accident, an internal memo had told staff not to use the faster emergency button unless the "main control panel cannot be reached."
Brown said that the female operator had also been told during training "not to worry about the button."
When the accident occurred, she signaled operators at the main control panel to use the "slow" stop button, as the memo had instructed, instead of pressing the other primary button, resulting in the loss of valuable seconds.
Senior Constable Steven Cornish, who also testified on Monday, said that use of the main button might have prevented the deaths of the four passengers, even if it had been pushed after the collision.
"It wouldn't have avoided (the tragedy), it may have limited some injuries," said Cornish, according to the Brisbane Times
The inquest also heard that staff received no drill training on how to react in emergency situations.
Ken Fleming, the counsel assisting the investigation, said that the accident "has been felt Australia-wide."
The CEO of Ardent Leisure, which owns Dreamworld, donated her annual bonus of $127,672 to the Red Cross to support victims after the accident. She later stepped down, and Ardent Leisure demolished the ride last year.
No automatic switch
Cornish also challenged the idea that the accident was "totally unforeseeable."
"The potential for that to happen was always there," Cornish said.
"If safety mechanisms were in place to stop the ride upon the drop in the water level the rafts would never have got to the point that they got to."
Cornish said there was no automatic sensor or switch that halted the ride if water levels were too low -- the problem which investigators believe led to October's deadly accident.
Operator intervention was only way to stop the ride in the case of an emergency.
The fatal accident wasn't the first incident in the ride's history, or even on that day. The ride had malfunctioned twice earlier that afternoon before the accident; the staff simply reset the failed pumps and "operating continued as per normal," Brown said.
According to ABC, the ride has had numerous other incidents over the years, ranging from colliding flumes to visitors falling overboard.
Ken Fleming, the counsel assisting the investigation, described a 2001 incident in which a raft flipped during a 'dry run' with nobody on board. It was so serious that a staff member had written in an email at the time, "I shudder when I think if there had been guests on the ride."
Fleming said that these previous accidents and malfunctions will be examined in the inquest.
Brown and Cornish were the first of 37 witnesses who will testify over the next two weeks. After June, the inquest will resume in September.