At Reef Encounters, we've been closely following the news story of the Japanese divers lost in Bali. We're saddened to hear that not all survived, but relieved that some have been brought to safety.
A lost diver situation is the worst nightmare of every dive guide and boat captain. Fortunately, such incidents are rare and when they do occur, there are usually procedures for resolving them before they get ugly. The reality is that most of these procedures necessitate a certain level of preparedness on the part of divers, guides and crew and unfortunately, a lot of divers, professional or otherwise, show up unprepared. It is not our intention to pass judgement on the divers, guides or boat captain in Bali. We merely wish to remind divers about the importance of certain safety procedures and equipment while such matters are in the news. What happened in Bali could easily happen in places like Yonaguni or Ishigaki, so Okinawa divers please take note.
So, we begin with equipment. What should a diver take along to reduce the risk of becoming lost at sea? At a minimum, every diver should carry a surface marker buoy, a spool or reel with enough line to shoot the buoy at depth and an auditory signalling device such as a whistle for use on the surface. Additionally, divers would be well advised to carry a signalling mirror and a flashlight, even in the daytime. If conditions are likely to be particularly treacherous, it may be advisable to carry a Lifeline two-way radio an ELT. Combined, all of these can virtually ensure that a lost diver won't be lost for long.
The surface marker buoy serves two purposes. First, it helps the boat crew keep track of divers while they're under water. Shooting an SMB during a dive allows the boat to track the location of a dive team under water when conditions are too challenging to simply watch their bubbles. Had the Bali divers deployed an SMB while they were still under water, it's possible that the boat captain would have seen it when he returned and known exactly where they were. A brightly coloured buoy might also have helped the captain spot them in the waves once they surfaced.
A whistle or other signalling device might have let the divers alert the captain or crew members of other boats to their presence. It can be hard to see divers even with an SMB and the auditory signal might help orient searchers as to their general direction, narrowing the search area considerably. However, the range of such devices is limited and the sound usually has to compete with wind engine noise.
If the SMB and auditory signal fail, a mirror can really come in handy. It can be seen from up to 10 miles away in some cases and is much easier to spot than a diver and SMB. If all members of a dive team are carrying them - and they all pull out their mirrors at once - they'll be hard to miss. Of course, their usefulness is greatest on bright days. When it's dark or overcast, there isn't much light to reflect - and light only helps when searchers are looking in the right direction.
What do you do when you know people are looking for you but you can't see them and they can't see you (i.e. because of heavy swells, dense fog or precipitation)? If you have a Lifeline radio, you can simply contact the boat (if they have a radio, that is) and tell them where you are. If you don't know (no visible land reference), you can at least let them know you are alive and on the surface. Worst case, you can hit the Emergency Locator Transmitter button, which will send your location via satellite to search and rescue authorities. The radio will allow you to maintain communication with search and rescue teams looking for you, helping you avoid the all-too-common situation in which the diver can see the searchers but the searchers can't see the diver. If the divers in Bali had taken one or more Lifelines with them, they'd have been found sooner.
Nobody ever wants to get lost at sea and it's best to plan dives to minimize the risk of this happening. But stuff happens and when it does, having the right equipment and knowing how to use it can save your life.
A lost diver situation is the worst nightmare of every dive guide and boat captain. Fortunately, such incidents are rare and when they do occur, there are usually procedures for resolving them before they get ugly. The reality is that most of these procedures necessitate a certain level of preparedness on the part of divers, guides and crew and unfortunately, a lot of divers, professional or otherwise, show up unprepared. It is not our intention to pass judgement on the divers, guides or boat captain in Bali. We merely wish to remind divers about the importance of certain safety procedures and equipment while such matters are in the news. What happened in Bali could easily happen in places like Yonaguni or Ishigaki, so Okinawa divers please take note.
So, we begin with equipment. What should a diver take along to reduce the risk of becoming lost at sea? At a minimum, every diver should carry a surface marker buoy, a spool or reel with enough line to shoot the buoy at depth and an auditory signalling device such as a whistle for use on the surface. Additionally, divers would be well advised to carry a signalling mirror and a flashlight, even in the daytime. If conditions are likely to be particularly treacherous, it may be advisable to carry a Lifeline two-way radio an ELT. Combined, all of these can virtually ensure that a lost diver won't be lost for long.
The surface marker buoy serves two purposes. First, it helps the boat crew keep track of divers while they're under water. Shooting an SMB during a dive allows the boat to track the location of a dive team under water when conditions are too challenging to simply watch their bubbles. Had the Bali divers deployed an SMB while they were still under water, it's possible that the boat captain would have seen it when he returned and known exactly where they were. A brightly coloured buoy might also have helped the captain spot them in the waves once they surfaced.
A whistle or other signalling device might have let the divers alert the captain or crew members of other boats to their presence. It can be hard to see divers even with an SMB and the auditory signal might help orient searchers as to their general direction, narrowing the search area considerably. However, the range of such devices is limited and the sound usually has to compete with wind engine noise.
If the SMB and auditory signal fail, a mirror can really come in handy. It can be seen from up to 10 miles away in some cases and is much easier to spot than a diver and SMB. If all members of a dive team are carrying them - and they all pull out their mirrors at once - they'll be hard to miss. Of course, their usefulness is greatest on bright days. When it's dark or overcast, there isn't much light to reflect - and light only helps when searchers are looking in the right direction.
What do you do when you know people are looking for you but you can't see them and they can't see you (i.e. because of heavy swells, dense fog or precipitation)? If you have a Lifeline radio, you can simply contact the boat (if they have a radio, that is) and tell them where you are. If you don't know (no visible land reference), you can at least let them know you are alive and on the surface. Worst case, you can hit the Emergency Locator Transmitter button, which will send your location via satellite to search and rescue authorities. The radio will allow you to maintain communication with search and rescue teams looking for you, helping you avoid the all-too-common situation in which the diver can see the searchers but the searchers can't see the diver. If the divers in Bali had taken one or more Lifelines with them, they'd have been found sooner.
Nobody ever wants to get lost at sea and it's best to plan dives to minimize the risk of this happening. But stuff happens and when it does, having the right equipment and knowing how to use it can save your life.