On Saturday, June 23, 2018, 12 members of a local Thai football team, who were between the ages of 11 and 16, and their 25-year-old assistant coach, entered Tham Luang Nang Non Cave for a day of exploration.
What should have been a fun day turned into a nightmare when early monsoon rains flooded the cave, which sits on the border between Thailand and Myanmar, cutting the boys off the entrance. The group clambered 2.5 miles (4 km) from the cave entrance before taking refuge on a rocky plateau that remained above the water.
At 7 p.m., the football team’s head coach received calls from concerned parents asking where their children were. The coach ran to the cave entrance and found the boys’ bikes still parked outside, and alerted Thai authorities. On June 25, 2018, Thai Navy SEALS began a search of the cave, which was hampered by near-constant rainfall.
The world reacts
In what is an astonishing coincidence, a British cave explorer named Vern Unsworth was exploring Tham Luang Nang Non cave and lived nearby, and he suggested that the Thai government contact the British Cave Rescue Council (BCRC) . Three highly specialized BCRC cave divers arrived at the cave on June 27, followed on June 28 by a team from the US Air Force’s 320th Special Tactics Squadron, 31st Rescue Squadron. The next day, divers from the Australian Federal Police Specialist Response Group arrived at the cave, followed by a Chinese team from the Peking Peaceland Foundation.
While the Thai authorities were looking for another way to enter the cave, such as drilling from above, two of the BCRC divers, Richard Stanton and John Volanthen, along with Belgian diver Ben Eeymenants and French diver Maksym Polejaka, started laying guidelines. through the murky waters of the cave. Increasing rainfall forced all divers to withdraw from the cave until July 2, 2018. When Stanton and Volanthen finally discovered the boys, they were all, unbelievably, still alive, although very hungry.
Thai Navy SEALs, along with BCRC divers and Australian and Chinese diving teams, began transporting tanks of breathing gas into the cave system, while several Thai Navy SEALs and a Thai army doctor nursed the boys. In total, an estimated 10,000 people have taken up residence at the cave’s entrance, including the Thai military, engineers, government officials, volunteers, news media and the boys’ families.
To prevent the rising water from drowning the boys, engineers were able to pump more than 1 billion liters of water from the cave, but that didn’t stop the oxygen level in the cave dropping to dangerous levels. It took highly experienced cave divers six hours, swimming against the current, to reach the boys, and five hours, swimming with the current, to leave the cave. Rescuers doubted the boys could remain calm while wearing scuba gear and staying underwater during that time, especially since many of the boys didn’t know how to swim.
No more time
With a forecast of additional monsoon rains flooding the cave until October and rapidly decreasing oxygen levels in the cave, rescuers decided on July 8 to make a rescue effort with the help of 13 international cave divers and five Thai Navy SEALs. Four British divers, Stanton, Volanthen, Jason Mallinson and Chris Jewell, along with two Australian divers, Craig Challen and Richard Harris, entered the cave, supported by 90 Thai and foreign divers who would conduct medical check-ups on the boys at various points. and provide fresh air tanks.
In addition to being a cave diver, Harris was a doctor, sedating the children, and because the sedatives only lasted about an hour, Harris trained the divers to re-inject the boys.
When they reached a gathering point deep in the cave, hundreds of volunteers passed the children along zip lines installed by mountaineers. Each boy wore a full-face mask and was attached to the guide rope and to a diver in front, who also carried the boys’ oxygen tank. A second diver followed each boy with a flashlight.
When they reached a dry room at the cave entrance, the boys recovered from the anesthetic and walked outside.
On July 8, four boys were rescued and four more were rescued the following day. On the third day, the last four boys and their coach were rescued.
Finally, the three Thai Navy SEALs emerged from the cave and the army doctor who had stayed with the boys. However, when they reached the assembly area, room 3, the water began to flood the cave and they, along with the 100 rescuers still inside, were forced to make a frenzied flight to the cave entrance, where they escaped unharmed. The cave claimed two lives: former Thai Navy SEAL Volunteer Saman Kunan died placing air cylinders along the escape route, and a year after the rescue, Thai Navy SEAL Beirut Pakbara died of a blood infection he contracted while in prison. the cave.
The most dangerous sport
Cave diving is so dangerous because divers cannot swim vertically to the surface, but they have to return to the cave entrance. To be successful, cave divers must undergo rigorous training, the first level of which includes entering the above-ground environment of caves, managing guidelines and line reels, breathing gas planning, propulsion techniques, and communication techniques.
The second level of training, apprentice cave training, involves using sidelines outside the main guideline, navigating multiple jumps, or gaps, in a guideline, and decompression techniques. Further training includes cave mapping and mapping techniques.
In 1979 Sheck Exley published the book, Basic Cave Diving: A Blueprint for Survival, which broke down the factors that contributed to cave diving accidents. The five factors Exley identified are:
- Education – cave divers must not exceed their level of education, and academic training must be accompanied by practical experience.
- Management guideline – in addition to attaching a directive from a point outside a cave, additional tie-offs must be made inside a cave and directives must not fall into traps; line arrows, which are notched triangles, should be placed on guidelines to provide both visual and tactile references to exits, orientation, and the locations of jumps.
- Breathing gas management – divers must use the “rule of thirds”, where one third of the breathing gas is used for entry, one third for exit and one third is kept as an emergency reserve; the use of secondary gas systems is also encouraged.
- depth management – because caves plunge deep into the ground, divers may inadvertently exceed their expected depth, which can affect their breathing gas consumption and increase the need for decompression.
- Relief – a cave diver must carry a minimum of three independent light sources, the first of which is intended for use during the dive and the other two as backup lights; each light must have a burn time of at least the planned duration of the dive, but the backup lights may be of a lower power.
Cave divers use different breathing gas tank configurations than open water divers, and they also inhale mixed gases, such as: trim mix, which consists of oxygen, helium and nitrogen, and nitroxwhich consists of nitrogen and oxygen.
Cave diving was developed in the 1930s in the United Kingdom when members of the Cave Diving Group (CDG) explored the flooded caves of Somerset. Underwater warfare was pioneered during World War II, and much surplus equipment became available after the war. The 1960s brought the first use of the wetsuit, which provided both insulation and buoyancy, SCUBA air systems, fins, and helmet-mounted lights.
Cave diving took off in the US in the 1970s, but with no official training, fatalities began to mount. This was especially true in the state of Florida, which came close to banning cave diving completely within its borders. Today, popular cave diving sites include Grand Bahama Island and north-central Florida, home to the longest-explored underwater cave systems in the US: the Leon Sinks and Wakulla Springs.
A wild ride
For sheer excitement, nothing beats the cave diving of American engineer and cave diver Bill Stone. In 1998, Stone led more than 100 volunteers to explore Wakulla Springs. Stone then partnered with NASA to produce an advanced autonomous underwater vehicle (AUV), and he participated in a project to develop a vehicle capable of exploring the subterranean seas of Jupiter’s moon Europa.
In December 1987 in Wakulla Springs, Florida, Stone used a rebreather of the Cis-Lunar MK1 model to stay submerged for more than 24 hours, using only half the capacity of the system. In 2010, author James Tabor wrote: Blind Descent: The Search for the Deepest Place on Earth. It describes Stone’s explorations of the Mexican caves Huautla and Cheve, and the Ukrainian Alexander Klimchouk’s exploration of the Krubera cave in the Republic of Georgia.
Cave divers continue to push the boundaries of what’s possible as they explore and map the deepest places in the world.