Inquest: Contaminated air found in scuba accident victim's tank

A trainee diver whose decomposed body was recovered three days after he went missing at Pulau Hantu had a scuba tank that was filled with toxic gases.Mr Sue Qing Wen's body was found floating in the sea off the island on Feb 20 last year with the compressed air tank still strapped onto his body.
The tank, which should have contained (about 21 percent oxygen and 78 percent nitrogen), was found instead to have 785 parts per million (ppm) of carbon monoxide and 12.3 ppr of hydrogen sulphide.
According to Associate Professor Philip Eng of the Department of Respiratory Medicine, Singapore General Hospital, that level of carbon monoxide would make a person dizzy, nauseous and convulse within 45 minutes, and unconscious within two hours.
After a three-day inquiry, State Coroner Victor Yeo returned an open verdict on Friday. He said there were many unexplained questions surrounding Mr Sue's drowning.
Neither could it be determined conclusively the effect of inhaling the toxic gases had on him and how the tank came to be contaminated with such a high level of carbon monoxide.
At an earlier hearing, the court heard that Mr Sue, the eldest of three children, had enrolled with Dolphin Dive and Adventure for an open water diving certification in January 2007.
After two theory lessons and water training in a pool, he had to take a final assessment at a dive site in the sea off Pulau Hantu.
On Feb 17, he was part of a group, including five other students, who left Keppel Marina for Pulau Hantu. Mr Sue was paired with Mr Mohamed Fairus Jumali, 35, for the test.
They were to dive to the seabed following a 35m long anchored line for seven exercises.
Two dives were completed without any problems. Before the third and last dive, all six divers changed their tanks.

While Mr Sue was descending with his buddy, Mr Fairus had moved aside for a pair of divers to go up. He then saw Mr Sue let go of the anchored line and did not know why.
Instructor Gerald Chew signalled to Mr Fairus to find out where Mr Sue was but the latter was not sure.
Mr Chew dived to the bottom to look for Mr Sue but could not find him. He alerted his colleague on a boat.
The colleague, Ms Joanne Sim Hui Jun, was helping someone up the boat when she saw Mr Sue surfacing a distance away without his breathing apparatus.
She signalled to him to put on the regulator and to inflate his buoyancy compensator device, a vest worn by divers which can be inflated or deflated to control the level of buoyancy.
A lifebuoy attached to a rope was thrown to him but it was too short. Mr Sue was last seen waving his hands before sinking in the water with strong currents pushing the divers away from the boat.