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- - CO2 Levels (https://www.subsim.com/radioroom/showthread.php?t=212838)

What is the maximum acceptable level of carbon dioxide inside your boat before you need to surface?

I'm trying to push it to the very limits because I am now stuck in a hostile port, I'm trying to sneak out because there are destroyers and gunboats all around, thankfully they haven't detected me yet. They're on high alert because I just sunk 2 docked merchant ships.

CO2 levels are over 10% - been submerged for hours. The CO2 indicator in the top right corner is saying I need to surface ASAP.

Quote:

Originally Posted by depthtok33l (Post 2200082)

It really doesn't matter what the maximum tolerable level is. In your current situation, you have no choice but to push for as long as you can. Surfacing would be suicidal, or at the very least, a one-way ticket to a POW camp and the end of a promising career. You are already at 2x the established toxic limit. Either the game will kill your crew or you will be fortunate and get away. Might as well press on.

Godspeed.

I've consistently run my CO2 levels up to 20% with no adverse effects, you should be safe for awhile. Given the choice between possible bad things happening (staying submerged), and guaranteed bad things happening (surfacing and getting blown to pieces), it's not really a choice; you stay down and pray.

That gauge doesn't seem to reflect percentage of CO2. It seems to represent percentage of CO2 until toxicity is reached. IE 100% on the gauge is toxic, whereas in real life it's something like below....

1,000,000 ppm of a gas = 100 % concentration of the gas, and 10,000 ppm of a gas in air = a 1% concentration.
At 1% concentration of carbon dioxide CO2 (10,000 parts per million or ppm) and under continuous exposure at that level, such as in an auditorium filled with occupants and poor fresh air ventilation, some occupants are likely to feel drowsy.
The concentration of carbon dioxide must be over about 2% (20,000 ppm) before most people are aware of its presence unless the odor of an associated material (auto exhaust or fermenting yeast, for instance) is present at lower concentrations.
Above 2%, carbon dioxide may cause a feeling of heaviness in the chest and/or more frequent and deeper respirations.
If exposure continues at that level for several hours, minimal "acidosis" (an acid condition of the blood) may occur but more frequently is absent.
Breathing rate doubles at 3% CO2 and is four times the normal rate at 5% CO2.
Toxic levels of carbon dioxide: at levels above 5%, concentration CO2 is directly toxic. [At lower levels we may be seeing effects of a reduction in the relative amount of oxygen rather than direct toxicity of CO2.]

I've run the gauge to nearly 100% before while slinking around in enemy harbors with no ill effects on the crew. As I recall, O2 levels return to 100% almost instantly upon surfacing too.

You'll be dead at 100% ... ignore everything else.

As already mentioned, 100% is toxic. I try to remain below 50%, but have gotten higher.

In an emergency, you can poke the conning tower up just high enough to open main induction, then duck back down, but you are risking getting shot quickly by alert destroyers.

Stick it out on silent running as deep as the water will allow and head for the nearest open water.

My advice to you, steer away from their port and when it's dark enough go ahead and surface.

My advice, not much over 12% or 18% max.
Your crew will die. Watch the crew screen.

I've often gone to 90% CO2, testing aspects of battery performance. It doesn't have any effect on crew; another flaw in the game, really. It is sort of like the way your deck watch can endure the worst weather the same as if it was sunny and pleasant.

As has been stated 100% is lethal, .... 'curtains for certain'. Depending on class & maybe number of crew(?) - a rough rule of thumb I use is approx 48 hours submerged for a fleet-boat before I need to surface and 'air the boat'.

Happy Hunting!