Marine department officials should have noticed there were too few life jackets and lifebuoys on Lamma IV when they inspected the ship before the October 1 collision, a naval expert told the Lamma disaster inquiry on Thursday morning.

Naval architect Dr Neville Armstrong also said it was “important” for marine inspectors to check a vessel against the original design drawings submitted to the department. The drawing for Lamma IV showed a watertight door, which was missing on the boat, he noted.

Surveyors and inspectors should have checked the number of life jackets and lifebuoys on the ship, Armstrong said. Thirty-nine people died in last year’s collision between the vessels Lamma IV and Sea Smooth.

On Wednesday Armstrong told the commission of inquiry that the number of life jackets on board Lamma IV was below British and Australian standards – which require enough for all passengers.

Lamma IV was carrying 65 lifebuoys – one for every two people – and 92 vests, the commission has been told. On the night of the collision there were 127 people, including three crew members, on the ship.

The hearing continues on Thursday afternoon.