He told the commission he was taking four types of heart medication and had medical clearance to work as a ferry master. He said he caught a cold in March which left him with a persistent cough for which he bought some medicine.

He said he notified his manager he was taking the cough mixture but did not read a warning on the box which said it may cause drowsiness and: "If affected do not drive a vehicle or operate machinery". He took the cough mixture for more than a week without noticing any side effects, including fatigue.

In evidence, he said he was in ultimate control of the ferry as its master but it was not uncommon to hand over control of ‘the sticks’ to other qualified crew, to allow for short breaks and for other staff to gain experience.

After Mr Sclater drove the ferry from Circular Quay to Pyrmont Bay, arriving at 9am, he said he started to feel tired and sat down on the settee in the wheelhouse. The commission heard he closed his eyes and must have drifted off but believed he was only “absolutely unconscious” for about five minutes. When he awoke at around 9.34am he said he noticed his line manager in the wheelhouse and rose to his feet.

The ferry master said the reason he became drowsy and fell asleep was a combination of his underlying illness, not having taken his morning heart medication and taking the cough mixture. His doctor also said he was particularly sensitive to codeine.