Decompression sickness becomes a factor in underwater search The perils of the rescue and salvage mission on a sunken tugboat off Tuen Mun were underscored yesterday when two divers were caught in dangerous situations on a day when the first two bodies were recovered. The incidents were disclosed by marine officials, who said the recovery of the Ukrainian supply tugboat Neftegaz-67 from the muddy seabed could take more than a week. The bodies of two of 18 missing seamen were found early yesterday after the divers for the first time gained access to the hull. One body was found in the auxiliary engine room at about midnight and the other in the locker room at 2.20am. Chief fire officer Chow Wing-tak said only five of 32 cabins had been searched and the further the divers went, the more dangerous it became. One diver's air hose became entangled in floating objects inside the hull yesterday afternoon, and he had to be released by his standby diver. 'The time he stayed in the water exceeded the safety limit, and he had to undergo decompression for 50 minutes before reaching the surface,' Mr Chow said. 'It is very fortunate that his condition is OK, and he resumed his part in the rescue operation later.' In the morning, another driver developed decompression sickness while searching for bodies. He received treatment in a decompression chamber on a fireboat and was later sent to a clinic to be examined. The marine officials could not say how long it would take to search all the cabins on the 80-metre vessel. 'The sizes of the rooms and their distances vary, while the currents change really fast,' Mr Chow said. Divers can enter the water only four times in 24 hours when the tides turn and the powerful currents sweeping the seabed become weaker. Each 'window' can accommodate up to three diving operations. Diving coach Steve Chan said it was important for the divers to be safe as the situation inside the cabin was very dangerous. 'It is no more a rescue operation, so it's not worth jeopardising the lives of our divers,' he said. 'The wreck should first be lifted up, and then get the bodies out.' Thirty-two diving attempts had been made between the collision last Saturday and yesterday afternoon. Director of Marine Roger Tupper said an agreement was being worked on with the owner of the sunken ship and the salvage operator to lift the wreck from the seabed. 'But these operations take time, and we are looking at at least seven days - possibly 10 - if things go smoothly to get the [salvage] vessel on station. That is the advice from the salvage contractor,' Mr Tupper said.