The Curious World Of Saturation Divers

Saturation divers are the rock-stars of the diving world. This type of diving is worlds apart from scuba diving. It’s very niche and tends to attract a nomadic, adventure seeking, high risk tolerance and gritty profile. Is $2000 a day enough to get you out of bed?

For the travel aficionados this industry offers visiting locations a Westerner may only hear about from a CNN Foreign Correspondent but less frequently visit. With work opportunities available in countries such as Angola, Azerbaijan, Turkmenistan, Kuwait, Equatorial Guinea work can be both exotic and interesting.

Dive crew are sourced from around the world with several crew members being from the host country where the job is taking place. Crew may come from diverse countries such as India, Sweden, South Africa, Singapore and Australia. Diving companies arrange travel to the host country where dive crew often join the work vessel by helicopter if they don’t sail with the ship to the worksite. Usually somewhere in the ocean where shore isn’t visible even with a climb to the ship’s helideck.

What Saturation Diving Looks Like

For diving work deeper than 50 meters, closed bell mixed gas diving is required.

Rather than performing a dive than decompressing immediately, saturation divers will spend up to 28 days at a time living in a pressurized chamber allowing them to do multiple divers before a final decompression is done.

Teams of divers (often 6 or 9) will bring their clothes and toiletries into a approximately 20 cubic meter chamber where they will eat, sleep and shower for up to 28 days before leaving. Once the divers are in the chamber and valve checks have been done the chamber commences blowdown (pressurized with breathing gases equivalent to the diving depth the divers will be working at). Saturation divers don’t breathe regular air like the rest of us. At depth, nitrogen (which makes up nearly 79% of air) behaves like an intoxicant on our bodies. We call this condition “Nitrogen Narcosis”. We replace nitrogen with helium and as the saturation chambers are blown down to depth, oxygen percentages are reduced according to partial pressures derived from Dalton’s Law.

After blowdown has been completed and gases have cooled from compression the atmosphere inside is stable.

Saturation chambers are artificial environments that require continuous and careful monitoring. Usually checked hourly and recorded in a logbook. Carbon dioxide is continuously monitored and scrubbed from the chamber using fine soda sorb particles that have to be changed once saturated with gas. Oxygen is also monitored and can be toxic in too high of a concentration and fatal if too low of a concentration. Chambers are periodically injected with oxygen to ensure levels remain as prescribed in company diving manual. Temperature and humidity are carefully monitored and controlled as gas passes through heating units.

Divers receive meals and supplies through external locks that equalize with the chamber’s pressure or when items need to be removed from the chamber, the locks are vented. Effluent is also emptied from the chamber with a holding tank and a series of valves.

How Do Divers Get To Work?

A large metal sphere locks onto the diver’s living chamber and equalizes pressure so that divers can safely transfer to and from the bell. Once the transfer is complete, the lock between the bell and living chamber is vented and the bell is lowered into the water until it reaches the work depth. Believe it or not, the bottom latch of the bell is open and water does not enter the bell. This is because the gas inside the bell pushes against the water that would try entering the bell keeping the standby safety diver and the inside of the bell perfectly dry. Like the diver’s living chamber, the bell has its own life support system with backup gases. Working divers have hot water circulating through tubes in the suits and breath from umbilical supplied gas. Diving in-water shifts are maximum eight hours from time of lock off until bell locks back onto living chamber.

What Do Saturation Divers Do?

With dive crew, ship crew and ship costing $300K a day or more for hire, nearly all saturation diving work is commissioned by oil and gas companies. Saturation dive crew are hired for construction or maintenance of offshore oil and gas installations. They might be tying in pipe fittings for a platform or replacing damaged pipe.

There is little natural light in the depths divers work in. Since diving occurs in shifts around the clock weather permitting, it’s always dark. Humungous structures are lowered into the water by cranes and finding the worksite can require direction. Communication with diving supervisors is critical to keep the divers safe.

If This Job Is So Dangerous, Why Do They Do It?

Many saturation divers have a lot of freedom in where they choose to live. I’ve worked with expats living in Thailand, France, Dominican Republic, Croatia and a whole slew of other countries. You’ll encounter characters in that industry you won’t come across in a regular nine to five job. People who get into wild shenanigans and grand projects when not working. Build their own homes, start interesting side hustles. It’s a special psychological profile who can share a 20 cubic meter chamber with other men for nearly a month without getting squirrely. Saturation diving is as close as one can get to being an astronaut without the crazy selection process.

Now that I’ve romanticized this job, what are the downsides? You are away from family and loved ones. A lot. This can strain many relationships.

Work can be unpredictable. One year you can have more work than you could want. The next year could see work slow down as geopolitics and economics impact forecasts and opportunity costs for businesses.

Diving is inherently risky, especially saturation diving with its artificial environment and inability of people from outside to intervene if emergencies arise. Decompressions take days if medical assistance is needed.

Working at sea, weather can pose hazards or impede vessel crew changes.

Whatever reasons you may have for wanting to enter this unusual and fascinating profession, rest assured you will have entertaining tales and unique friendships.