VIDEO: A Coast family enjoys the Thunder River Rapids ride last week before Tuesday's tragedy.

SUNSHINE Coast graphic designer Jemma Wiltshire was at Dreamworld 30 minutes before four people died on what is understood to be one of the safest rides in the complex.

Ms Wiltshire was at the popular theme park for work as she had been involved in completing an acrylic panel for the tiger exhibit.

It was while driving home and people were contacting her that she discovered what had happened.

"I have been on that ride before," she said.

"I didn't go through the park at all (this time), but it does make you feel sick to the stomach to think people went there today and they didn't get to leave."

Rebecca Moore (right back) with husband, Tony (left) and children going into Dreamworld
Rebecca Moore (right back) with husband, Tony (left) and children going into Dreamworld

But Sunshine Coast mum, Rebecca Moore, knows the Thunder River Rapids Ride pretty well.

It was the only ride she chose to go on when visiting Dreamworld with her family last week.

"I went on the ride with the whole family," she said.

"It was fairly gentle compared to other rides and was the only one I would go on.

"I have a neck problem so I only go on rides that don't hurt my neck too much.

"It is not a dangerous ride, it is like the family ride. This is why we are all so shocked."

Mrs Moore said it was a "tragedy" and the family sent their thoughts and condolences to those involved.

"We love Dreamworld," she said.

"We are so sad for the families and friends involved. It's just devastating.''

Details of what caused the tragic death of four adults, aged between 32 and in their early 40s, are still coming through.

Police have confirmed it involved the conveyor belt of the ride.

Dreamworld will be closed as Workplace Health and Safety Officers investigate the incident.