Suggestion: Liquid Air Upgrade for Rebreather

[slapz]

The technical term for liquid air is perfluorocarbon (PFC). PFC is a synthetic liquid fluorinated hydrocarbon. Basically, it’s a liquid that can hold three times the oxygen and four times the carbon dioxide as human blood. Also, it does wonders for cooling/heating.

Essentially the stuff is ♥♥♥♥ing amazing, especially when it comes to diving.

Humans can actually breathe PFC like it's air - a no brainer then that 200 years in the future PFC would be the standard for deep sea exploration. Imagine breathing in a watery substance, only to have the sensation of fresh air filling your lungs. The reason a liquid solution is superior to a pure gas is not only that the liquid has a greater oxygen capacity, but that the liquid prevents your lungs from imploding under extreme pressure (also you don’t have to ♥♥♥♥ around with the nitrogen-oxygen mix crap that deep sea divers use).

Another cool thing is that the liquid ventilation (LV) can regulate body temperature. The depths are a cold and unforgiving place. It’s nice not to freeze to death. In experiments, mice could be conditioned to breathe an oxygenated saline solution, and then survive under the pressure of 160 atmospheres… that’s one mile below the surface! With a LV you could easily dive to 1600 meters. Also, there is no need for slow decompression (if such realism is implemented). With PFC in the lungs there is less worry about drastic decompression given that a person's lungs have a lower change in volume while ascending.

LV technology is realistic and based in fact. The Exosuit might very well enable great dives, but it would be nice to be able to freely swim around. LV would undoubtedly use PFC tanks and would have greater efficiency at depth. Perhaps there could be a fragment that you obtain with the aid of the Exosuit - this would enable free dives.

Anyways, feel free to give your two cents. :)

[bugzapper57]

The main 'problem' gas involved in decompression is actually NITROGEN. Roughly 70 per cent of air is nitrogen. 'The Bends' (a.k.a: 'Decompression Sickness') is a result of not spending enough time waiting at specific depths in order to allow dissolved nitrogen to safely diffuse out of the diver's bloodstream while ascending. There are a number of dive-planning tables and automatic decompression meters available to enable divers to determine the depth and duration of DC stops during the ascent. Naturally, it is possible to dive to around 120 feet (36.58 metres) and spend roughly 3 minutes at that depth ('bounce dive') without incurring any decompression time, although it is highly advisable to make a 'safety stop' around 15 feet and wait for 10 minutes just to make absolutely certain.

Decompression is basically a function of dive depth, dive duration, nitrogen absorption at a given depth for a given time, offset by the time it takes to safely diffuse that nitrogen out of a diver's bloodstream during a series of rigidly programmed stops made at specific depths.

Nitrogen starts to become toxic at approximately 90 feet (30 metres). N2 Narcosis is the result. It's quite similar to being drunk on alcohol. An affected diver's thoughts and actions become increasingly irrational, and this effect intensifies with prolonged exposure and increasing depth. Helium is added to 'technical diving gas mixes' to minimize the effects of Nitrogen Narcosis, and these mixes of Nitrogen, Oxygen and Helium (sometimes Hydrogen) must be carefully blended at the cylinder filling station in order to be safe to use at a specified depth. Helium and hydrogen molecules are so small that they will readily diffuse out of the human bloodstream or even through a dive cylinder's walls... The infamous 'Mouse Effect'. - Hydrogen and helium do not actually contribute to The Bends. It is always Nitrogen.

Carbon dioxide content is actually minimal compared to nitrogen and oxygen. in fact, this gas triggers the breathing response in humans, although it does not appear to contribute any hazardous effects until its partial pressure exceeds normal concentrations of 0.04% in an environment pressurized to 1 ATM.

High-Pressure Neurological Syndrome (HPNS) is essentially a nastier variant of Nitrogen Narcosis, but caused by a combination of helium in the gas mix and high ambient water pressure; generally experienced at extreme depths exceeding 1,000 feet (300+ metres).

For these reasons, recreational divers are advised to limit their maximum depth to 120 feet, and stay within an acceptable bottom-time limit that avoids the need to make decompression stops, or at least minimize bottom times to allow safe decompression using their current tank contents. Generally, a full dive cylinder and regulator is attached to the decompression stop(s) at the appropriate level(s) of a weighted safety line ('shot line') or a boat's anchor chain.

[bugzapper57]

Fluid breathing systems DO indeed exist. There are a number of drawbacks associated with breathing an oxygenated fluorocarbon emulsion, not least of which is an immediate sensation of drowning when using a FBS for the first time. There's a scene in James Cameron's film, 'The Abyss' that appears to accurately demonstrate what that sensation would be like.

There are three possible (realistic) solutions to deep diving in the Subnautica world-frame.

1. Advanced Modular Diving System: Basically a cryogenic gas storage SCUBA rig with cylinders that contain Oxygen, Nitrogen and Helium (or other inert gases), computer controlled to add each gas at a suitable partial pressure for any given depth. The AMDS also functions as a closed-circuit rebreather capable of removing carbon dioxide via a scrubber canister, and returns the exhaled air mix to a pressurized storage system, extending the amount of oxygen available to the diver.

2. Artificial Gill System: This also exists, although the amount of membrane material required to filter enough O2 directly out of seawater, plus enough space to accommodate circulating pumps and a battery power supply, plus several deep-diving gas mix cylinders means that it would be too bulky to use if constructed using current technology. The original prototype was roughly the size of a small-ish wardrobe. It worked, too. The AGS could easily exist in the Subnautica universe, though. Advanced materials, nano-fabrication methods and some clever script writing is all that's necessary to make this one a reality, so to speak.

3. One-ATM Armoured Dive Suit (a.k.a: 'Exo-Suit'): The easiest fix of them all. It's basically a highly advanced JIM suit engineered to withstand abyssal (10,000 metres +) pressures. A wearable bathyscaphe, configured to mimic and amplify human movement and musculature. The diver/pilot is fed an air supply at a normal surface pressure of 1 ATM, and the structural strength of the suit materials alone withstand the ambient water pressure.

Note: There are blueprints for an Exo-Suit already available in Subnautica, although it seems that there is no clear idea of how it should work in relation to the game's current mechanics.

I would suggest treating it like a vehicle capable of docking with the Cyclops or an undersea base; recharges its power automatically when docked, and able to provide at least one hour of 'real-time' life support while operating at extreme depth.

[Lord General Nacho]

So much science in this thread I'm gonna become a diving/biology expert at this rate

[slapz]

Origineel geplaatst door bugzapper57:

Fluid breathing systems DO indeed exist. There are a number of drawbacks associated with breathing an oxygenated fluorocarbon emulsion, not least of which is an immediate sensation of drowning when using a FBS for the first time. There's a scene in James Cameron's film, 'The Abyss' that appears to accurately demonstrate what that sensation would be like.

There are three possible (realistic) solutions to deep diving in the Subnautica world-frame.

1. Advanced Modular Diving System: Basically a cryogenic gas storage SCUBA rig with cylinders that contain Oxygen, Nitrogen and Helium (or other inert gases), computer controlled to add each gas at a suitable partial pressure for any given depth. The AMDS also functions as a closed-circuit rebreather capable of removing carbon dioxide via a scrubber canister, and returns the exhaled air mix to a pressurized storage system, extending the amount of oxygen available to the diver.

2. Artificial Gill System: This also exists, although the amount of membrane material required to filter enough O2 directly out of seawater, plus enough space to accommodate circulating pumps and a battery power supply, plus several deep-diving gas mix cylinders means that it would be too bulky to use if constructed using current technology. The original prototype was roughly the size of a small-ish wardrobe. It worked, too. The AGS could easily exist in the Subnautica universe, though. Advanced materials, nano-fabrication methods and some clever script writing is all that's necessary to make this one a reality, so to speak.

3. One-ATM Armoured Dive Suit (a.k.a: 'Exo-Suit'): The easiest fix of them all. It's basically a highly advanced JIM suit engineered to withstand abyssal (10,000 metres +) pressures. A wearable bathyscaphe, configured to mimic and amplify human movement and musculature. The diver/pilot is fed an air supply at a normal surface pressure of 1 ATM, and the structural strength of the suit materials alone withstand the ambient water pressure.

Note: There are blueprints for an Exo-Suit already available in Subnautica, although it seems that there is no clear idea of how it should work in relation to the game's current mechanics.

I would suggest treating it like a vehicle capable of docking with the Cyclops or an undersea base; recharges its power automatically when docked, and able to provide at least one hour of 'real-time' life support while operating at extreme depth.

We are getting an exosuit in-game, but it’s more of a mecha. Of course, that means the pressure vessel is more durable than a traditional ADS which has to pressurize ligaments and joints. I think it is going to be slower, but more versatile version of the seamoth – having the ability to walk on the ocean floor and use a mining implement of some sort.

[Rickenbacker]

This would be a really neat future addition. You'd have to recharge "air" at a base (can't just pop above the survace, of course) and would be able to go deeper than with regular breathing tanks. Sounds like a fun addition, down the road.

[bugzapper57]

Origineel geplaatst door Nachoguy5:

So much science in this thread I'm gonna become a diving/biology expert at this rate

That's what SCUBA diving is all about.

An interest in marine biology is just another neat way of putting your diving skills to good use.

As soon as you even contemplate getting wet to any serious degree, your first thought should be "Where's the nearest PADI/FAUI - accredited dive school?"

SCUBA training courses vary in duration and content. In general, don't expect to see any big numbers on your depth gauge or unchlorinated water for at least six to ten weeks. Completion of a basic 'C Card' open water SCUBA diving course is the absolute bare minimum required before you should even consider buying your own cylinder(s) and regulator. A wetsuit, weights, mask, fins and snorkel are quite okay to buy on a passing whim. However, if you want to go deeper, you will need to undergo a medical examination first, be properly trained in SCUBA theory and all the physical skills needed to pass written and practical examinations. A diver may also be required to safely complete specific tasks (ditch and recovery, buddy-breathing, free ascent, diver rescue, etc.) during a series of open-water dives and achieve a passing grade before C-Card certification is issued.

The reason for all of this rigamarole? PHYSICS. Understand it, or die.

The world's oceans and all they contain will cheerfully kill you in the blink of an eye...
And that's just when you're on the surface. As you go deeper, the potential for peril intensifies exponentially.

If you're planning to do a bit of SCUBA diving during your next vacation, don't expect to receive any serious level of training if the 'Training Course' can be completed in a single day.

Seriously, could you learn to fly a plane or drive a car LIKE A BOSS in a single day?

Nope.

This is the absolute minimum level of skill to be considered a properly 'Certified Diver'.

You should be required to read, think, eat, sleep and poop 'Diving' for no less that six to ten two-hour (or longer) sessions comprised of theory and practical elements. You should also be provided with a hefty chunk of reference material and a Diver's Log Book.