A former government ship surveyor has told the commission of inquiry into the Lamma sea disaster that there is no specific regulation on how seats should be fixed to the deck of a boat.

Wong Chi-Kin, retired Marine Department principal ship surveyor, told the inquiry on Thursday that regulations only required the seats to be properly fixed.

“Ship inspectors would judge them by experience,” he said.

Many seats became detached from the deck of the Hongkong Electric boat Lamma IV after the collision with the ferry Sea Smooth off Lamma Island on October 1, trapping passengers as the Lamma IV sank.

Wong said the inspectors would try to shake the seats by hand and ask people to sit on them to test stability.

They would not usually inspect how the seats were fixed to the deck unless they were in doubt. The fixtures were under the deck and difficult to inspect, he said.

His subordinates inspected the seats of Lamma IV, installed in the 1990s, but found no problem with them.

The hearing continues.