Three days after the disappearance of the Titan submarine, rescue crews are racing against time to locate its five passengers. Although there have been some indications that they may still be alive, what caused the submarine to disappear and what its fate is still unknown.

However, the risks for the five passengers if they are alive are many according to experts. The five missing could feel pressure on their lungs, face “nitrogen narcosis” syndrome and hypothermia if the submarine’s hull ruptures.

In case they have tried to breach the hull, while the vessel was in the depths of the ocean, experts explain that the chances of survival of the passengers are almost zero.

Pulmonary pressure

Dr Nikolai Rotherman, a deep-sea ecologist at the University of Portsmouth, said that if such an accident had occurred, the high pressure would have killed the passengers almost instantly.

“If there had been any kind of breach in the hull, the occupants would have died in the ocean almost instantly, given the pressure of over 5,500 pounds per square inch exerted by the ocean at a depth of 3,800 meters.”

Professor Alistair Greig, a marine engineering expert at University College London added that if the hull had been breached anyway, the “prognosis is not good”.

Specialized equipment, such as special gas mixtures to combat the intense pressure in the ocean depths, have allowed divers to reach depths of about 1,700 feet. But even whales that have evolved to feed in the ocean depths reach up to 10,000 feet. The deep ocean is so inhospitable in part because of the pressure. Once people go underwater, they have to deal with the pressure of the water, which is much denser than the air, that surrounds them. At the location of the Titanic wreck, the pressure would be about 380 times greater than that experienced by people on the surface.

As the pressure from the water increases, it causes any air-filled space to collapse. For damaged submarines, this can then lead to a rupture, possibly injuring the passengers inside. And for the lungs, intense pressure can be devastating.

This pressure can be felt at a very basic level by swimming in the deepest part of a pool as the water pressure begins to affect the air in the ears. But at extreme depths this pressure becomes deadly.

An unprotected man exposed to the depths where the Titan wanted to go would feel his lungs collapse and his eardrums burst from the pressure of the water. Water would then enter his mouth and the result would be suffocation. Humans can survive about 15 minutes without oxygen, although they pass out much sooner, and brain damage is possible after a few minutes without oxygen. air.

However, in the event that the Titan has sustained any damage it is almost unlikely that the pressure would have crushed the occupants’ bones however great the pressure because such catastrophic injuries can occur with diving suits containing air, which are then deformed by the pressure, then crushing the wearers bones.

Nitrogen intoxication syndrome

At the same time, at high pressures found in the depths of the sea, the internal body chemistry begins to change. This causes nitrogen, which is part of the air we breathe, to become more soluble, causing a dissolved form of the gas to enter the blood. As human tissue needs oxygen, not nitrogen, to survive, this imbalance causes a condition called nitrogen narcosis – with the body effectively suffocating from the inside out.

Hypothermia

But even if they are not faced with one of the above factors, hypothermia is also a dangerous factor.

The deep ocean receives little to no light and temperatures at 12,500 feet are about 2°C. In humans, hypothermia can occur in water as cold as 4°C (40°F), and people begin to feel tired and confused.

If the boat has no power, its five passengers will be in total darkness and temperatures of around 3°C as the boat rolls on the seabed.

Various air-breathing creatures such as whales, seals, and sea turtles have evolved special adaptations to compensate for going so deep. Some species preemptively stop using their lungs and slow down their bodily functions before plunging to the depths, surviving on the oxygen that remains in their blood. Others have expandable and strong internal structures to prevent the pressure from collapsing the tissues.