Saturation diving is a standard method of working in the commercial diving world. Divers live in a pressurised environment or 'SAT system' for many weeks. Once their work duty has finished the divers are decompressed to surface pressure over a period of hours or days.
Today SAT time is limited in many countries. In Norway the maximum bottom time is 14 days and the diver needs to be offshore no more than 21 days. Meanwhile in the British North Sea the time in SAT (including decompression) is limited to 28 days. However there is no limit on statutory offshore time, hence the diver can remain offshore for a number of days before being transported back to the mainland.
Scientists also embrace the invaluable in-water time that SAT diving facilitates. In 1970 Dr Sylvia Earle lead the first all-female team of aquanauts in Tektite II. Missions typically lasted between 10 and 20 days.
In 1993 'Aquarius Reef Base' - an undersea research laboratory - was deployed in 18 metres / 60 feet of water in the Florida Keys National Marine Sanctuary. This lab has enabled scientists and astronauts unparalleled access to the ocean allowing them to study ocean reefs, climate change and ocean acidification. Over 120 missions have been conducted producing 600+ scientific published research papers based on Aquarius science.
Now a new mission involving Aquarius has just been announced for 2018. The plan is that the undersea research expedition 'Project Poseidon' will run for 100 days. 'Splashdown' is currently scheduled for 4th May 2018.
Those selected to join the Project Poseidon aquanaut crew and dive team include: rebreather instructor trainer and author Dr. Jeffrey Bozanic; retired NASA astronaut Dr. Scott Parazynski; National Park Service archeologist Jessica Keller and Nicole Stott. Nicole is the current world record holder for longest saturation dive by a female and a veteran of the NASA Extreme Environment Mission Operations (NEEMO) mission 9 aquanaut crew.
Although this project does not start proper for 24 months, Project Poseidon has also confirmed that it will start its public outreach programme on 13th June 2016 with a free virtual summer camp for children aged 8 - 18.