12/07/2026
Come for a walk through the inside of a diving bell.
Getting a diver to the job is the biggest difference between Saturation Diving vs Air Diving
And it's all controlled from here, unlike what the Hollywood version of Last Breath dictates.
The the bell is mated onto the dive system onboard the vessel. We climb into the bell, take a seal on the doors, vent the trunk, and disconnect from the system.
The bell then gets lowered to depth though a moonpool or over the side of a vessel. The internal door can only be opened once the bell internal depth and the outside pressure are equal.
In this 3 man bell, there's 2 divers and one bellman. The diver get their gear on and lock out for 6 hours each.
The Bellman remains in the bell as an emergency standby diver, monitoring all the life support and emergancy systems the divers need.
Main Gas supply & emergency onboard supply pressures.
Checking bell sealing faces and orings
Power supplies & onboard back up batteries.
Divers gas reclaim systems, bell atmosphere, emegancy communication systems.
Emptying Divers Gas Reclaim system water trap.
Monitoring bell internal atmosphere and communications with the surface.
Controlling maximum umbilical lengths for the divers at a given depth
Hot water supply to the divers, CO2 scrubbing systems for bell internal atmosphere
Onboard He02 (Heliox) and O2 (Oxygen) banks
Every now and again, we top up the oxygen levels in the bell by giving ourselves an O2 injection. It's calculated based on the partial pressure reading from the PPO2 meter.
Hot Water can be channelled in multiple directions to find a ballance of heat, pressure and comfort. Temperature is controlled from the surface and pumped down to us.
When the divers are due to lock back in, we'll come up on their umbilical slack in a french coil and flood the bell up slightly to make it easier for them to climb in with their gear on. See my previous post for a short hyperlapse of this.
At depth you're isolated so we carry spares for nearly everything. O'rings, cameras lights, communications equipment, most typical failure points are covered. Plus emergency gear like suits, medical equipment and lung powered scrubbers. Also consumables, that might be required.
