At the entrance to the cave, scuba divers see this sign:

https://i.ndtvimg.com/i/2016-10/stop-your-death-sign_650x400_71476791136.jpg

It's necessary: a bit more than one person per year dies while scuba diving in that cave. Already, in January of 2018, a 50 year old man from Delaware died scuba diving in that cave. In 2017, a man and his teenage son died while trying out their Christmas present (new scuba gear) in the cave.

You see, a typical scuba class doesn't teach you the skills you need to dive inside of a cave. Even the classes you have to take to become a SCUBA INSTRUCTOR do not teach you the skills you need to dive in a cave.

To dive in a cave, you need to obtain a four part certificate that teaches you, in stages, the basic skills you need to survive in a cave. Only at the very end do you become qualified to dive inside of a cave. Each stage takes a lot of time, and a lot of money too.

But people are impatient. They think they can just go into a cave without all that training. Many of them go into a cave, realize that they no longer can see natural sunlight, panic, and get lost. Others don't know how to swim without kicking up silt from the cave bottom: they create "blackout conditions", panic, and get lost. Others find the labyrinthine cave confusing - and so they panic and get lost. Still others don't have the correct mixture of gas in their tank for cave diving: they become disoriented from gas, they panic, and get lost. Others hear that cave divers use lines to retrace their steps, so they try to do that: and the line runs out, the line gets tangled up, they panic, and get lost.

In any event death comes the same way to all of these: unable to find a cave exit in time, they run out of oxygen and they die. A very common trend in finding cave diving victim bodies that that the body is curled up near a small fissure in the cave: in their dying moments, untrained cave divers delude themselves into thinking that some small crack in the side of the cave is big enough for them to fit through and escape.

(http://www.autoadmit.com/thread.php?thread_id=3903717&forum_id=2#35484562)

In parts of this underwater cave system, the floors are covered in fine gravel or silt and if a flipper so much as brushes the surface, the stirred-up sediment completely obscures a diver's vision, effectively blinding them.

Free-diver Diego Adame recorded his terrifying near-drowning in the caves, after he lost a flipper and had to jettison his weight belt in a dash for the surface.

Don Dibble, a nearby dive shop owner who is usually the one to pull the remains of dead divers out of the cave, attempted to seal of the depths of the well by installing a gate to stop people from going too deep. Shortly after, he found the gate destroyed with a note saying "You can't keep us out." Although extremely dangerous, it seems the cave is too alluring to stay away.

(http://www.autoadmit.com/thread.php?thread_id=3903717&forum_id=2#35484614)

(http://www.autoadmit.com/thread.php?thread_id=3903717&forum_id=2#36383500)