Extensions that allowed Dreamworld to operate the Thunder River Rapids ride without a proper safety inspection were "unprecedented", an inquest into four deaths on the attraction has been told.
Workplace Health and Safety director of licensing and advisory services Johanna Sutherland said Dreamworld was granted two extensions to obtain annual engineering inspections of the attraction.
"It was first time (WPHS) had granted an extension ... there were no policies in place to allow the extension," Ms Sutherland said on Tuesday.
She said the decision to allow the ride to continue operations "concerned" her, but ultimately the decision was made by WPHS chief safety engineer Michael Chan.
Two months after the extension was granted, Cindy Low, Kate Goodchild, her brother Luke Dorsett and his partner Roozi Araghi, were killed on the ride.
Mr Chan told the inquest he met with Dreamworld general manager of engineering Chris Deaves and head of safety Angus Hutchings on August 14, 2016.
The pair told Mr Chan they had been unable to secure a registered engineer to perform a safety audit as part of the registration process.
"They proposed that the department accept the maintenance regime in lieu of an annual inspection by a professional engineer," Mr Chan said.
"I explained that such a proposal was unacceptable," Mr Chan said.
The annual inspection must be performed by a suitably experienced person and not by a system, he said.
"Just because you have a maintenance and safety system, I cannot say you are good to go."
Dreamworld was granted the extensions with Mr Chan saying the delay "would not introduce significant risks" to the park's continued operation.
The final deadline to complete the annual audit was December 1, 2016 when the ride would have been shut down by WPHS.
WPHS officers and procedures are the focus of the sixth week of the inquest which continues on Wednesday.
Australian Associated Press
