Last Sunday (18), a tourist submarine which had intended to visit the wreck of the Titanic which lies about 370 miles off the coast of Newfoundland, Canada, in the North Atlantic Ocean, went missing with five people on board. Since then, rescue teams have been racing against time to find the missing.. This Wednesday (21), three more vessels arrived at the search site, one of them with side scan sonar capabilities.

Currently, people aboard the Titan submersible would have less than 24 hours of oxygen supply. US media have reported a leaked internal memo sent to the US Department of Homeland Security which indicates that a Canadian aircraft detected underwater “tapping noises” at 30-minute intervals originating from the search area.

CNN International also reported an internal update sent Tuesday evening suggesting more sounds had been picked up. An hour after the news reports, the US Coast Guard confirmed that a Canadian search plane had picked up “underwater noise”. Of most concern to the responsible authorities is the period of oxygen available to the ship’s crew. On the internet, a commotion has been created around the subject and the possible consequences for the health of those on board.

What risk does this crew face?

The submarine has a system that, according to initial reports, could hold people for 96 hours, at first. That is, it would offer conditions similar to the atmosphere, with 20% oxygen, 78% nitrogen, and a few other gases, as explained Álvaro Pulchinelli, toxicologist at Clínica Felippe Mattoso, Grupo Fleury to O Globo newspaper.

“In the submersible, the idea is that this system remains balanced for 96 hours. Over time, this ratio deteriorates. Due to the lack of exchange and the carbon dioxide retained in the capsule, they become slower, have difficulty in becoming aware, drowsy, until narcosis occurs, when the person becomes unconscious. In the worst case, they will not feel an impending suffocation, they will be out.explains the specialist.

To conserve oxygen as much as possible, the ideal would be to remain calm and still, but the extreme psychological situation must also be taken into account. “They should rest as much as possible, reducing demand to try to make the mix more productive. A person in good physical condition, who has good oxygenation and who is not tall, could even spend less, but we spend a lot of fuel to stay alive, there is nothing to do. And how do you stay calm in this situation? The psychological must be terrible.says the toxicologist.

possible symptoms

A US Navy doctor revealed the 4 “symptoms” that the crew of the missing submarine can feel right now. In addition to being lost in the ocean, the 5 people could suffer from panic, tremors, hypothermia and tachycardia.

Hypothermia can be a worrying factor. Indeed, the bottom of the sea can reach 5º C. As a result, the body can develop tremors to increase the temperature, which “expends” more oxygen. With the decrease in oxygen available in the submarine and the increase in CO2, the crew may experience headaches and even pass out.

Additionally, the buildup of carbon dioxide (CO2) is toxic, which would further harm the situation the crew members find themselves in. Finally, claustrophobia and the fear of getting lost in the ocean can cause the crew to panic. Panic is accompanied by tachycardia, difficulty breathing and body rigidity.