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Thai cave rescue: How the boys were saved Thai cave rescue: How the boys were saved
(1 day later)
The Thai cave complex where 12 boys and their football coach became trapped is a snaking system of caverns and crevices which posed a range of problems for rescuers.The Thai cave complex where 12 boys and their football coach became trapped is a snaking system of caverns and crevices which posed a range of problems for rescuers.
Some stretches of the Tham Luang cave are more than 10m (33ft) high, while others are a tight squeeze through water-filled passages.Some stretches of the Tham Luang cave are more than 10m (33ft) high, while others are a tight squeeze through water-filled passages.
The death of an experienced former Thai navy diver, who was part of a team trying to supply the boys' cave with oxygen tanks, emphasised the dangers of the mission.The death of an experienced former Thai navy diver, who was part of a team trying to supply the boys' cave with oxygen tanks, emphasised the dangers of the mission.
The group of boys and their coach were exploring the caves when a sudden storm caused the passageways to flood, trapping them inside. They had spent nine days in the cave with little food or light when they were discovered on Monday 2 July.The group of boys and their coach were exploring the caves when a sudden storm caused the passageways to flood, trapping them inside. They had spent nine days in the cave with little food or light when they were discovered on Monday 2 July.
Rescuers initially wanted to keep the group supplied underground until the end of the rainy season - which would have taken months.Rescuers initially wanted to keep the group supplied underground until the end of the rainy season - which would have taken months.
But with the forecast of heavy rains, and the risk of water levels rising, an operation was launched on Sunday, 8 July, to bring them out.But with the forecast of heavy rains, and the risk of water levels rising, an operation was launched on Sunday, 8 July, to bring them out.
How did the boys escape?How did the boys escape?
Rescue divers with specialist breathing equipment reached the group through a series of water-filled passages.Rescue divers with specialist breathing equipment reached the group through a series of water-filled passages.
The boys had to be brought out the same way.The boys had to be brought out the same way.
Two divers accompanied each boy, one holding the boy close under his body and the other diver following behind. The divers guided them through the dark using ropes. Sources in the rescue operation, including divers who took part, told the BBC that the boys were heavily sedated ahead of the rescue to prevent them panicking in the dark, tight, underwater passageways.
In narrow sections, rescuers had to take off their air tanks and squeeze the boys and the tanks through. The boys were fitted with full-face breathing masks. For the underwater sections, they were strapped to a rescue diver, with another diver following behind. The divers were guided through the dark by dive lines. In narrow sections, rescuers had to take off their air tanks and squeeze the boys and the tanks through.
The boys were given anti-anxiety medication to prevent them panicking as they were brought out. The diving option was considered extremely dangerous by some, but dive experts said the priority was to get the boys out before the rains brought more flooding and debris into the cave system.
Each boy was given a full face mask - thought to be easier to use for novice divers. In walkable sections which had been drained of floodwater, the boys were bundled into stretchers and carried or winched along ropes, according to footage released by the Thai Navy Seals.
The diving option was considered extremely dangerous by some, but British dive experts said the priority was to get the boys out before the rains brought more flooding and debris into the cave system. Each journey back to the entrance took several hours.
Martin Grass, Chairman of the Cave Diving Group, said the rescuers would probably instruct the boys not to hold their breath, to use their fins slowly and breathe gently.
He said the boys would have two divers each chaperoning them, "to make sure they don't panic".
"It could be a bonus that the boys are young. When you're young, you feel invincible and they'd see it as a bit of an adventure," he said.
It is thought the boys spent 10 to 15 minutes under water at a time, depending how much of the passageways were flooded. Each journey back to the entrance, which also involved walking and scrambling through narrow spaces, took hours.
The rescue mission started on 8 July, with divers entering the cave at 10:00 local time (03:00 GMT). The first boy emerged at 17:40 and by 19:47, three more had followed.The rescue mission started on 8 July, with divers entering the cave at 10:00 local time (03:00 GMT). The first boy emerged at 17:40 and by 19:47, three more had followed.
All four were taken to hospital. The mission was paused overnight for air tanks to be replaced along the route but resumed again on Monday when four more boys were brought out. The mission was paused overnight for air tanks to be replaced along the route but resumed again on Monday and Tuesday until the remaining boys and their coach were brought out and transferred to hospital.
The pumping continued to try to reduce the flooding, and Chiang Rai provincial governor Narongsak Osottanakorn, who was leading the operation, said that water levels inside were now at their lowest levels so far. This was reported to have made more sections walkable than earlier in the week.
Divers took hundreds of compressed air tanks into the cave, and established a base camp inside a chamber.
The final four boys and their coach were brought out today (Tuesday 10 July).
Waiting and pumpingWaiting and pumping
There was a round-the-clock pumping operation to try to clear the caves.There was a round-the-clock pumping operation to try to clear the caves.
But as fast as the water was being pumped out, more was flowing in, fed by sinkholes and streams in the hills above, and the risks from the imminent monsoon rains was high.But as fast as the water was being pumped out, more was flowing in, fed by sinkholes and streams in the hills above, and the risks from the imminent monsoon rains was high.
Mr Narongsak said the mission was "a race against the water". Mr Narongsak said the mission had been "a race against the water".
Drilling downDrilling down
The authorities did try to drill holes in the cave walls to help drain some of the flood water - although the thick rock hampered efforts.The authorities did try to drill holes in the cave walls to help drain some of the flood water - although the thick rock hampered efforts.
There were also suggestions that drilling could be another way to get to the boys and lift them out.There were also suggestions that drilling could be another way to get to the boys and lift them out.
But to even begin the process, new roads would need to be built up above the caves to accommodate the heavy drilling equipment needed to break through the rock. But to even begin the process, new roads would have been needed to be built up above the caves to accommodate the heavy drilling equipment needed to break through the rock.
A detailed survey of the area would also be needed - otherwise there would be little chance of digging a hole in the right place to reach the boys and their coach. Drilling could also destabilise rocks above the children or block passages and increase flooding. A detailed survey of the area would also have had to be done - otherwise there would be little chance of digging a hole in the right place to reach the boys and their coach. Drilling could also destabilise rocks above the children or block passages and increase flooding.
What were the dangers down there?What were the dangers down there?
The boys, aged between 11 and 17, and their 25-year-old coach had been huddled on a small rock ledge. The environment was wet, so they had to keep warm and dry or risk hypothermia.The boys, aged between 11 and 17, and their 25-year-old coach had been huddled on a small rock ledge. The environment was wet, so they had to keep warm and dry or risk hypothermia.
There were concerns about the level of oxygen in the air in the space where the boys were trapped. Officials said at one point that the level of oxygen in the air had fallen to 15%. The usual level is 21%.There were concerns about the level of oxygen in the air in the space where the boys were trapped. Officials said at one point that the level of oxygen in the air had fallen to 15%. The usual level is 21%.
Rescuers transferred about 100 oxygen tanks to the cave to help improve the air supply.Rescuers transferred about 100 oxygen tanks to the cave to help improve the air supply.
Thai diver PO Saman had been helping transfer the tanks when he got into difficulties on the way back and did not have enough air himself. He died after losing consciousness in one of the passageways and his colleagues could not revive him.Thai diver PO Saman had been helping transfer the tanks when he got into difficulties on the way back and did not have enough air himself. He died after losing consciousness in one of the passageways and his colleagues could not revive him.
Read more:Read more:
What help have they received? What help did they receive?
Much-needed food and medical supplies, including fresh water and paracetamol, reached the boys and their coach on Tuesday. Rescuers transferred supplies to the boys to build up their energy and nutrient levels.Much-needed food and medical supplies, including fresh water and paracetamol, reached the boys and their coach on Tuesday. Rescuers transferred supplies to the boys to build up their energy and nutrient levels.
Rear Admiral Apagorn Youkonggaew, head of the Thai navy's special forces, told reporters they were given "easy-to-digest, high-energy food with vitamins and minerals, under the supervision of a doctor". Rear Admiral Arpakorn Yuukongkaew, head of the Thai navy's special forces, told reporters they were given "easy-to-digest, high-energy food with vitamins and minerals, under the supervision of a doctor".
Officials said most of the group were unhurt, although some were weak or had minor injuries.Officials said most of the group were unhurt, although some were weak or had minor injuries.
How did they deal with the mental strain?How did they deal with the mental strain?
The boys may have had torches or lights on mobile phones, but they had potentially been sitting in the dark for hours.The boys may have had torches or lights on mobile phones, but they had potentially been sitting in the dark for hours.
So rescue teams took lighting into the chamber and kept the group company.So rescue teams took lighting into the chamber and kept the group company.
Divers also brought letters from the boy's parents to help them handle the strain.Divers also brought letters from the boy's parents to help them handle the strain.
"They're mentally stable which is actually pretty good," Ben Reymenants, a Belgian diver helping with the rescue operation, told AFP news agency."They're mentally stable which is actually pretty good," Ben Reymenants, a Belgian diver helping with the rescue operation, told AFP news agency.
"Luckily the coach had the sanity of mind to keep them all together, huddled together to conserve their energy, that basically saved them.""Luckily the coach had the sanity of mind to keep them all together, huddled together to conserve their energy, that basically saved them."