Suffocate while Living aboard a coverd boat

[ColR]

You say it's got two smallish vents. If you're that worried leave them open at night.


I put our home on AirBnB when we go away. They recommended a Co2 detector. I bought one for about $12 on Ebay. If you're really concerned buy one, but if you have even the smallest of vents I really doubt you have anything to stress about.

[Singularity]

Rounding each factor in the direction of safety:
-an average human uses about one kilogram of oxygen per 24 hour period (NASA says 0.84kg/day); assuming on the boat you are only moving about and sleeping, this will work
-one kilogram of oxygen occupies 27 cubic feet of oxygen at sea level at 70 degrees fahrenheit (actually 26.62 cubic feet)
-oxygen comprises 20% of the air at sea level (actually 20.9%)

So if we need 27 cubic feet of oxygen per day...when oxygen is only 20% of the air we breath...this means we need 135 cubic feet of air per 24 hour periody to survive. A 5ftx5ftx5ft space is 125 cubic feet. Unless you have a trailerable-size boat I can't imagine even worrying about the math.

If you are super bored or need convincing, pick an day with nothing else going on and breath 100% from an 80 cubic foot scuba tank while sitting on a chair somewhere. See how long it lasts, but plan on it being an all day affair.

As such you really don't have to worry about running out of oxygen. In theory and sometimes reality, if there is really ZERO air movement inside the cabin and you are confined such that you can't turn over easily, then the relative concentration of carbon dioxide that you just exhaled can sort of build up around your head where you exhale.* In fact this was a problem early in the space program where astronaut headache complaints (a common symptom of too much carbon dioxide in the blood) were written off as being related to fluid shifts, etc, associated with the zero-g environment where as in fact later it was recognized that the CO2 sensors that were being closely monitored were not near the astronaut's head while sleeping. Once this latter position was monitored, it was recognized that air movement need to increase around the astronaut's head to decrease the CO2 concentration from being re-inhaled. This is really not a concern down on earth.

So, in theory, if you have a heart or lung condition putting the world's smallest fan somewhere in the cabin would be all the intervention you would need to take. This all assumes an air-tight (like a spaceship) boat. If you're going in/out of the boat at least once a day...this in reality is all the air changing that needs to be done.

*One might wonder "if the CO2 is building up around my head...what about the oxygen? How can the oxygen get in there?" The super-short answer is don't worry about it. In fact the local (about your head) oxygen is decreased a little, but this is of no concern. In fact we routinely, during sleep, put ourselves into positions where we do not move air well, then we roll over, back to normal, then into a bad position, then roll over....all in a night's sleep.

Personally I'd worry more about getting in a car accident driving to buy some type of gas monitor (or the fan catching fire) than running out of oxygen or building up CO2, but that's just me.

[Singularity]

Originally Posted by Singularity

-one kilogram of oxygen occupies 27 cubic feet of oxygen at sea level at 70 degrees fahrenheit (actually 26.62 cubic feet)

This should read "occupies 27 cubic feet of space at sea level..."

[Formosa46AK]

Originally Posted by guyrj33

Eastward ho 24 you could pick up a finger clip oxygenation monitor at any pharmacy, it measures the oxygen (sPO2) in your blood, combined with a combo CO / smoke detector you'll be able to get some idea of your situation.

Sorry, but don't depend on pulse oximetry (sPO2 finger device) to save you from carbon monoxide poisoning.
Per an article for clarification: "Carbon monoxide molecules can attach to the patient's hemoglobin replacing oxygen molecules. A pulse oximeter cannot distinguish the differences and the reading will show the total saturation level of oxygen and carbon monoxide. If 15% of hemoglobin has carbon monoxide and 80% has oxygen, the reading would be 95%."
I used to work at a hyperbaric center so this info is well-known.
Also, for you smokers: "A pack a day smoker can have a 3% to 6% COHb level in the blood, two packs a day, 6% to 10%, and three packs a day, as much as 20%."
OK, I'm off my soapbox.
This can be dangerous. A pulse oximeter should not be used on people with smoke inhalation, carbon monoxide poisoning, and heavy cigarette smoking.

[roland stockham]

If there is no air flow you will not die from lack of 02 you will suffocate from excess CO2 so you need an alarm for that plus propane if used. Agree with the above you need to create ventilation both to cut down condensation and to reduce claustrophobia which is often triggered by stale air. You need TWO vents fore and aft and preferably with a directional cowl so that air is blown in one and sucked out of the other depending on wind direction.

[Tillsbury]

Originally Posted by Singularity

This should read "occupies 27 cubic feet of space at sea level..."

If his boat isn’t at sea level he will have more serious problems than which gases are nearby...

[Singularity]

Originally Posted by roland stockham

If there is no air flow you will not die from lack of 02 you will suffocate from excess CO2 so you need an alarm for that...

I'm sorry but this is wrong, scare-mongering, causes people to waste money on stuff they don't need. I stand to be corrected; please cite the science (by the numbers) or at least anectdotal evidence to support your claim.

For purposes in a discussion about sleeping on boats (assuming no fires or crazy diseases) suffocation means that you run out of oxygen. Excess CO2 is called hypercapnia which for all practical purposes in a discussion about sleeping in a boat is not a concern accept as stated in my previous post in this thread. It's not a concern.

If a boat cabin is so small that "running out of oxygen" is a concern when the boat is under a plastic wrap, then the boat cabin is too small to sleep in under any circumstance (wrap or no wrap).

[clownfishsydney]

Originally Posted by Spot

Without knowing all the details of the OP's heating and ventilation system it is hard to offer grounded advice. As minimally described I would be quite afraid to stay there too.

It would be a different story electric oil-filler radiator versus unvented propane 'sunflower' versus a righteous heater with an exhaust stack and intake for combustion air.

Also, detectors for smoke or CO or flammable gas or combinations thereof are not hard to find at home improvement stores and camping supply stores. I want to say they have been mandatory on RV's for a while now. I am planning to update my vintage RV with CO and flammable gas alarms.

CO detectors will not detect CO2 which is the potential problem here.

[clownfishsydney]

Originally Posted by Singularity

Rounding each factor in the direction of safety:
-an average human uses about one kilogram of oxygen per 24 hour period (NASA says 0.84kg/day); assuming on the boat you are only moving about and sleeping, this will work
-one kilogram of oxygen occupies 27 cubic feet of oxygen at sea level at 70 degrees fahrenheit (actually 26.62 cubic feet)
-oxygen comprises 20% of the air at sea level (actually 20.9%)

So if we need 27 cubic feet of oxygen per day...when oxygen is only 20% of the air we breath...this means we need 135 cubic feet of air per 24 hour periody to survive. A 5ftx5ftx5ft space is 125 cubic feet. Unless you have a trailerable-size boat I can't imagine even worrying about the math.

If you are super bored or need convincing, pick an day with nothing else going on and breath 100% from an 80 cubic foot scuba tank while sitting on a chair somewhere. See how long it lasts, but plan on it being an all day affair.

A small problem with all this is that you will have absolutely no oxygen left at the end. However, you will die long before this as you need at least a certain amount of oxygen in the air for you to survive. Certainly 6% is said to be the level for almost certain death, but someone who is not in the best of health may die with higher levels. From 14 to 16% you will have impairment even at rest and probably would not wake up as you should, so you would keep on asleep and using more oxygen.

The human body uses about 4% of the oxygen from every breath you take. This means that for a given quantity of air, you can perhaps breath it in twice before you will start to have not enough oxygen in the air to behave normally and three times and you are near the critical low level.

Therefore, you will be unconscious and dead a lot quicker than proposed above.

Also, if you sit and breath an 80 cubic foot scuba tank of oxygen at the surface, it will possibly last three hours at the most before it is all gone, not 24 hours. This is based on the tank being 11 litres in size, filled to 205 bar (not possible with oxygen which normally has a limit of about 160 to 170 bar) and a breathing rate of 13 litres per minute (a very good underwater rate and probably a normal resting state for most people). Remember, you can only breath the oxygen from the above tank once, each breath will waste all but a small amount.

Anyway, despite this, I agree you are very unlikely to have a problem, people sleep in closed yachts all the time and they only have small vents to exchange the air.

[hellosailor]

"CO detectors will not detect CO2 which is the potential problem here."
The body reacts quite differently to the two.
When CO2 rises, you'll probably wake up short of breath, breathing very rapidly, with a pounding headache and possibly dizziness. In short, you SHOULD WAKE UP feeling that something is very wrong.
In contrast, when CO levels rise you DO NOT WAKE UP. Period. You simply die.

And that's the main reason CO detectors are pushed, but CO2 detectors are usually the result of someone not understanding what the problems are, and that the gasses are different.

Medical conditions can lead to an internal excess CO2 buildup, even when there's plenty of fresh air around you. Detectors won't help with that, either.

[Singularity]

Originally Posted by clownfishsydney

A small problem with all this is that you will have absolutely no oxygen left at the end. However, you will die long before this as you need at least a certain amount of oxygen in the air for you to survive. Certainly 6% is said to be the level for almost certain death, but someone who is not in the best of health may die with higher levels. From 14 to 16% you will have impairment even at rest and probably would not wake up as you should, so you would keep on asleep and using more oxygen.

The human body uses about 4% of the oxygen from every breath you take. This means that for a given quantity of air, you can perhaps breath it in twice before you will start to have not enough oxygen in the air to behave normally and three times and you are near the critical low level.

Therefore, you will be unconscious and dead a lot quicker than proposed above.

Also, if you sit and breath an 80 cubic foot scuba tank of oxygen at the surface, it will possibly last three hours at the most before it is all gone, not 24 hours. This is based on the tank being 11 litres in size, filled to 205 bar (not possible with oxygen which normally has a limit of about 160 to 170 bar) and a breathing rate of 13 litres per minute (a very good underwater rate and probably a normal resting state for most people). Remember, you can only breath the oxygen from the above tank once, each breath will waste all but a small amount.

Anyway, despite this, I agree you are very unlikely to have a problem, people sleep in closed yachts all the time and they only have small vents to exchange the air.

The bottle example would last over 6 hours, assuming a minute ventilation of 6L a minute (common for sleep) from an 80cf bottle.

You otherwise do not seem to understand how the respiratory system works (brainstem, anatomic dead space, acid/base stuff, respiratory drive). One does not need to be a pulmonary specialist to understand this, but they do need more knowledge than scuba diving imparts and such knowledge is free in youtube lectures, etc.

Assuming a person goes to sleep in a berth provided by the manufacturer for sleeping and the person isn't going to be deeply unconscious from drugs or alcohol, then the person doesn't have to worry about carbon dioxide from breathing causing death.

For a roundabout review of what excessive carbon dioxide does (symptom-wise) while sleeping consider googling obstructive sleep apnea.

All this "you will not wake up/gonna die" talk serves no purpose other than to scare-monger...encourage people to waste money consulting experts or buying useless equipment.

[boatpoker]

Never heard of a CO2 fatality on a boat.
Lots of CO fatalities on boats. See Google.
Oxygen depletion can be a serious issue if a fuel burning (propane, diesel or kerosene) heater draws combustion air from inside the boat.

[Eastward ho 24]

I didn't see all the replies until today. Guess I'm being paranoid. Espically since I'm a boilermaker and I work in confined spaces with combination gas monitors and or under fresh air. I ought to know better just washed up know if this was something that happens to an unlucky few here and there. I wont be cooking or using combustion so c0 ought to be no danger. Was just not sure if this happens onboard. I did pull my hoses off the seacocks and I'm gonna duct a blower from the deepest part of the hull in can. I guess I am paranoid haha sometimes if I fall asleep in the car I get nervous to ha ha.

[hellosailor]

Eastward-
Boiler, tank, sewer workers all have special worries. And the ones that don't worry, sometimes get dead. But in my limited year of paying attention to all sorts of boating safety reports and statistics? I've never heard of even ONE historical incident where someone sleeping on a boat died, or received medical attention, or complained, of a CO2 problem.

You are quite possibly more likely to be attacked by a swarm of Africanized killer bees and killed by them, than to have a CO2 incident. And yes, bees like to build nests in the mast and boom, sailors get a rude surprise from them routinely.

Of course, you could probably get some government grant money to study those two areas, and look for statistical correlations. Along with fatal Hanza virus infections, from nice that sneak on board. And did we mention rat bites?(G)

[Singularity]

Originally Posted by Eastward ho 24

Guess I'm being paranoid.

Paranoid is believing that someone is going to do something bad to you while you're sleeping. You're not married, are you?

Originally Posted by hellosailor

Eastward-
You are quite possibly more likely to be attacked by a swarm of Africanized killer bees and killed by them, than to have a CO2 incident. And yes, bees like to build nests in the mast and boom, sailors get a rude surprise from them routinely.

Of course, you could probably get some government grant money...

Funny you should mention it, but I think you knew this.