You may have seen the story in this week’s news about a group of Thai teenagers trapped in a cave. The young footballers aged 11-16 along with their coach had entered the The Tham Luang Nang Non cave, a tourist attraction which runs for many kilometres underground in the Chiang Rai province of Thailand. Although the cave network is generally stable and safe, it also features underground rivers which on this occasion have become flooded by the seasonal heavy rain, trapping the group inside. So what are the dangers if you become trapped underground and what should you do to survive? We take a closer look.
As in any survival situation, staying calm is key. This will help you to think clearly and logically, think up a strategy for survival and escape and help to avoid both mental and physiological stress which can leave you weaker. If you are in a group and someone experiences a panic attack or anxiety, then it is important to help them relax and get back to their normal state as in some circumstances they may become a danger to themselves and others. Do not attempt to escape in a state of panic – it may impair your judgement and increase your risk of falling, and you may risk disturbing unstable sections, potentially worsening the situation.
Take time to carefully study the area you have become trapped in. Look for signs that the cave may experience rising water, such as slime, dirt or water lines on the walls. There may also be debris marking high water lines. Flooding is the biggest risk when trapped underground, so you should try to find the highest spot in the cave. Next, look for evidence of rockfalls. If there are areas of loose rocks that can shift easily, you will need to be aware and avoid disturbing them. Although not as common in natural caves, rockfalls are a risk but not usually an immediate danger unless there has been recent seismic activity.
The best way to avoid hypothermia is to stay warm and stay dry. It is almost always damp underground, and temperatures can be much lower than outside. Try to avoid getting clothing wet, and if you do have wet clothes, wring them out. If you are in a group, then huddling together will help to stay warm. It is recommended to always have a survival blanket in your pack, which will help to preserve your body heat.
Another key element of survival is hydration. If you are stuck in an underground cave that is full of water, you may think that this is one thing you don’t have to worry about – but you may be wrong. Caves can contain stagnant, dirty water that poses a risk of diarrhoea and vomiting, both of which could make dehydration a real problem. The key is to obtain drinking water from a moving supply such as a steady drip or running inlet. In any case, it is essential to stay hydrated so you may find that using dirtier water becomes a necessity if you are stuck for a prolonged period.
Make sure that you know exactly how much food you and your group have and ration it sensibly so that you can make it last out until you are rescued. This will help to ensure that you can maintain energy levels which you may need to alert rescuers to your presence and get out when the time comes.
If you are participating in a planned exploration of a cave, the chances are that you have appropriate lighting. If this is a case, you will need to ration your lighting to ensure that you do not end up trapped for what seems like an eternity in absolute darkness. Luckily, modern LED headlamps and torches with lithium cell batteries last for far longer than traditional torches, however they too will eventually run out. Becoming stuck in the dark is not dangerous itself, but is known to significantly increase mental stress in a situation such as this and this may become a real problem.
The best way to maximise your chances of survival in any situation is to be prepared. If you are planning to explore a cave, there are some measures you can take to reduce the risk. Pack the correct kit including extra rations, a first aid kit and a spare light. Most importantly, make sure somebody knows exactly where you are headed and knows what to do if you have not returned by a specified time window.