Hayley Williams, 16, fell to her death whilst riding Hydro at Oakwood Leisure Park in Pembrokeshire, Wales back in 2004.
Hayley's sister Hannah told the coroner's court that as they queued for the ride no safety checks were made. She said of the checks made as they boarded the ride: ''People seemed to be glancing but paying no attention whatsoever.'' However, the ride supervisor on the day said that visual checks were carried out.
Miles Mitchell, who was sitting in the back row of the ride, said he was certain no-one checked the seat belts. He said he was not aware there were belts and, as a result, rode the ride without one fastened.
The court heard that the ride was operated by a supervisor and an assistant who were responsible for ensuring passengers were strapped in before they went off. Gareth Etches, 24, who was the ride supervisor on the day, said checks were made.
Mr Etches told the jury it was the first day he had worked on Hydro and he had received 20 minutes' training under supervision. He was working on the opposite side of the boat to where Hayley was sitting, so a ride assistant would have been responsible for checking whether the teenager was safely secured. However, he said this was not always done physically but checks were visually made.
The ride assistant and senior management from Oakwood are due to give evidence when the inquest resumes on Wednesday.