I'm thinking there's a couple of candidates who seem unaware of those 'pesky' things called 'facts' and rather sprout off garbage...I'm sure there's a Darwin Award in the making here
Smoking
- Thread starter Vulcan
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Agreed but you seem to carry on. Basic understanding air goes into the engine, oxygen from that air is removed and the resultant gases from combustion emitted from the exhaust. The amount of oxygen in the exhaust substantially reduced from the amount taken in by the engine. It doesnt take long for the level of oxygen to be reduced such that it can no longer support life.
And your gas boiler doesn't have a cat does it, so it produces ballpark 50 times as much co as your car idling. Before cats were introduced your car would be producing around 90+ times as much CO as a modern cat equipped vehicle. So the level of CO would reach lethal levels very quickly.
But I repeat, in a modern cat equipped vehicle, you will die from asphyxiation long before CO poisoning gets you, because the CO represents 0.2% of the exhaust, the other 99.08% of which is incapable of sustaining your life. So you will die due to lack of oxygen long before CO can build to lethal levels. Those are the facts, go and do some sums.
But I repeat, in a modern cat equipped vehicle, you will die from asphyxiation long before CO poisoning gets you, because the CO represents 0.2% of the exhaust, the other 99.08% of which is incapable of sustaining your life. So you will die due to lack of oxygen long before CO can build to lethal levels. Those are the facts, go and do some sums.
Blackswanwood
Still Learning
Reading through the posts is it not the case that before improvements were made to petrol and diesel engines the exhaust fumes would kill you with the high level of carbon monoxide being the cause?
Now that engines have been improved the exhaust fumes will still kill but more slowly as the level of carbon monoxide has been greatly reduced and the cause of death will be suffocation as the gases in the exhaust fumes replace the oxygen in the air?
Don’t try this at home.
Now that engines have been improved the exhaust fumes will still kill but more slowly as the level of carbon monoxide has been greatly reduced and the cause of death will be suffocation as the gases in the exhaust fumes replace the oxygen in the air?
Don’t try this at home.
You will be dead long before the oxygen in the air is reduced to where it won't support life...
(I tend to be paranoid because I used to work welding in confined spaces in my younger days- where air supply quality is vital- people have died from air contamination)
Here you have to pass a specialised course before you are legally allowed to do 'confined space welding' and you get some pretty graphic warnings of what happens when people ignore the basic safety rules...
So when people start sprouting what you find behind the south end of a northbound male bovine- well I will say my piece- and back it up with actual facts...
Something notably lacking from the other side so far- just snide comments and innuendo...
So far, the ONLY person who has done so- is ME...
You made the claim that your car/garage is so airtight that oxygen can't get in to replenish what is used... step up and present your evidence of this rather extraordinary claim....
Short of supergluing your lips to the exhaust pipe and sealing your nostrils shut- NO car or building is that airtight that the oxygen in the air around you won't be replenished at a far greater rate than it is being used...
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Go and put your hand over your exhaust pipe with the engine running. You will notice there is a significant pressure.
Now consider some very basic physics or just plain old common sense.
Take a container, doesn't matter what it is, but let's say your car. It contains air at ambient pressure. Now introduce a pipe feeding gas into that space at above ambient pressure. What happens?
The incoming higher pressure gas displaces the lower pressure gas in the container. Any leaks actually provide an exit point for the gas being displaced, so in fact speed up the process rather than mitigating it in any way.
If the container were completely sealed then what would happen is that the existing gas would be compressed by that coming in until such time as the pressure equalised. How much of each gas would be present at that point would depend upon their relative pressures and the volume of the container.
It is of course likely that in our hose through the window scenario some of the incoming gas may also escape, but overall the process is entirely predictable and inevitable.
The incoming gas will wholly displace that which is already there. At no point in this process will fresh air from the outside be able to enter the space, because it is at a lower pressure that the gas coming in, which will immediately raise the pressure inside above ambient, and continue to do so until the whole space is at the same pressure as the incoming gas.
So the original air will be replaced by a mixture which is composed almost entirely of Nitrogen and Carbon Dioxide, and you will die.
Another way of looking at this is to think of a tyre. Let us say it contains air at 10psi, and you inflate it to 30psi, using say argon. It will now contain a mixture of argon and air, but heavily biased towards argon.
Now let's make a hole in it. Now if we pump argon into it at 30psi initially a mixture of the original air and argon will come out of the hole. This will very quickly change to pure argon as all the air is expelled. At no point will air somehow be able to sneak back in !
Typically an idling engine will consume in the region of 5-7 cubic metres of air per hour per litre of capacity, and convert it into an unbreathable gas cocktail so you can readily see that it won't take long to produce enough exhaust gas to fill your car and kill you.
You have obviously never worked in a clean room environment where this is the process used to prevent contamination, namely the pressure is maintained at a higher level than outside in order to prevent dust and other contaminants entering.
I have absolutely no desire to get into the unnecessarily antagonist debate above but I wondered if lack of oxygen to the car engine would cause it to stop before lack of oxygen to the individual caused them to die.
Please, only reasoned answers; it's a genuine question
Please, only reasoned answers; it's a genuine question
artie
Sawdust manufacturer.
If the individual was inside the vehicle and it was pretty well sealed with a pipe from the exhaust, where the engine got it's oxygen would be irrelevant
Edited in an attempt to be more coherent
Unfortunately not.
The reason being that the engine is actually much more efficient than we are at using the available oxygen. So yes it will eventually stop when the oxygen level falls below that necessary to support combustion, but by that time you will be long dead.
I am sorry you find the debate "unnecessarily antagonistic".
From my point of view I just find it really worrying that somebody might actually believe that the only thing to be concerned about in the exhaust from a modern car is it's CO content.
I have spent over 40 years working on a wide variety of vehicles, both professionally and as a hobby, and can most certainly assure you this is not the case.
Car mechanics most basic rule is you never, ever, run an engine in an enclosed space.
That is why any professional workshop will be equipped with a pipe that fits over the tailpipe to take the exhaust out of the building, most professional set ups have an extraction fan incorporated.That way if it's cold then you can shut the door and work in safety.
One mechanic friend of mine had a lucky escape. He had not attached the hose properly, it was a common design where the pipe is attached to the tailpipe of the car using what amounts to a built in mole grip. I have the same type in my workshop.
He hadn't done it up properly and it fell off. Fortunately he was found, pretty much unconscious.
He recovered pretty quickly once taken out in the fresh air.
Very quick in his case, he reckoned 15-20 minutes, because the car was running at speed on a rolling road. Idling it would obviously take a lot longer.
Can't actually recall the last time I used my extraction pipe.
Since his close call I always make a habit of having the doors fully open and the back of the car outside. Rather be cold than dead!
From my point of view I just find it really worrying that somebody might actually believe that the only thing to be concerned about in the exhaust from a modern car is it's CO content.
I have spent over 40 years working on a wide variety of vehicles, both professionally and as a hobby, and can most certainly assure you this is not the case.
Car mechanics most basic rule is you never, ever, run an engine in an enclosed space.
That is why any professional workshop will be equipped with a pipe that fits over the tailpipe to take the exhaust out of the building, most professional set ups have an extraction fan incorporated.That way if it's cold then you can shut the door and work in safety.
One mechanic friend of mine had a lucky escape. He had not attached the hose properly, it was a common design where the pipe is attached to the tailpipe of the car using what amounts to a built in mole grip. I have the same type in my workshop.
He hadn't done it up properly and it fell off. Fortunately he was found, pretty much unconscious.
He recovered pretty quickly once taken out in the fresh air.
Very quick in his case, he reckoned 15-20 minutes, because the car was running at speed on a rolling road. Idling it would obviously take a lot longer.
Can't actually recall the last time I used my extraction pipe.
Since his close call I always make a habit of having the doors fully open and the back of the car outside. Rather be cold than dead!
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Same here- I did my apprenticeship as an elec fitter and later added my auto elec ticket- and older vehicles WERE a killer if run in a closed workshop- BUT that has changed- although for comforts sake exhaust extractors should still be used, any modern vehicle is so much safer that it is basically impossible to die from carbon monoxide poisoning from it (and it is laughable to suggest that any building is so airtight that the engine could 'use up all the oxygen' so much so that the atmosphere inside becomes unbreathable and unable to sustain life...)
Indeed as the numbers 'I' did show (and no-one has bothered to show any showing otherwise) even the old 'run an exhaust hose in the back window' trick would be unable to kill you with any modern motor- diesel or petrol... (but diesel is even safer than petrol currently as the one thing that actually DOES have the potential to kill you (present in both petrol and diesel exhausts) is actually HALF the levels coming from a diesel than from a petrol motor!!!)
All this started from one person making a (incorrect) claim that 'diesels were killers' they emit such dangerous levels of pollution- thoroughly debunked- but by all means- don't let actual facts and figures stand in the way of a good old conspiracy...
