[neilep (OP)]

Dearest CommEWEtologists,


In my YEWEth I EWEsd to commEWE to London. My word, there were days it was soooo packed it was a joke. Now there were many a time when  the train would be stationary in a tunnel.



People really enjoying their commute last Tuesday. see how they smile ?






With a stationary packed train stuck in tunnel, what are the chances of oxygen deprivation ?


I presEWEme studies must have been done to look into this yes ? I wonder how ' Close to the Edge' the parameters are ?




whajafink ?






"Mind The Gap"


Sheepy
xxxxx

[Halc]

My word, there were days it was soooo packed it was a joke.

Imagine these guys stuck in a tunnel for long, and not even a loo

People really enjoying their commute last Tuesday. see how they smile ?

The foreground guy suspects that Ophelia there is doing something inappropriate, yet the offending grope origin actually is from the smiling guy just beyond him.

With a stationery packed train stuck in tunnel, what are the chances of oxygen deprivation ?

The tube, like any tunnel, is supposed to have continuous ventilation to deal with anything not moving, and also to carry away exhaust fumes. Not too much the latter in an electric subway, but think of the old days of steam trains going through long tunnels, windows shut due to the smoke of the engine. Tunnels could only get so long back then.

Lots of people stuck in say a 747 for 6 hours on the ground (done that) with ventilation that only works significantly when the thing is in the air.*  Nobody passed out for lack of oxygen, but the temperatures went through the roof. They let first class off, but not the cattle sections.


(*) that sentence had no verb

[alancalverd]

With a stationery packed train stuck in tunnel, what are the chances of oxygen deprivation ?

Office stationery doesn't consume oxygen, and whilst time spent packed in the stationery cupboard can be fun, I don't recall our hyperventilation being primarily caused by excess CO2.

[neilep (OP)]

With a stationery packed train stuck in tunnel, what are the chances of oxygen deprivation ?

Office stationery doesn't consume oxygen, and whilst time spent packed in the stationery cupboard can be fun, I don't recall our hyperventilation being primarily caused by excess CO2.
[/quote


DOH !!!!!! (goes to change typo)

[paul cotter]

Even in an apparently sealed container like the tube there would be many areas of leakage allowing air in and out and the body heat of so many sheep would create convection. Probably not sufficient without additional ventilation but it would enable a breathable o2/co2 ratio for quite some time.

[vhfpmr]

Imagine these guys stuck in a tunnel for long, and not even a loo

Just like the slave ships.

[alancalverd]

Oxygen extraction is about 0.25 liter/minute for an adult.

The smallest London Underground rolling stock has about 0.6 m headroom above the standing passengers, maybe 1.5 m above the seated ones. Say average headroom about 1 m Assume each passenger occupies 0.4 square meters. So you have 0.4 cubic meters of available air, or 80 liters of available oxygen, per capita if the train is fully packed.

So the crude answer is about 5 hours. However as the oxygen concentration depletes, so does its partial pressure, and folk begin to suffer below 10% of atmospheric pressure, so expect some fainting and collapse after 2.5 hours.   

Problem is, however, that as CO2 levels rise, people begin to hyperventilate and panic well before the level becomes toxic, so you are more likely to die in a crowd surge than from asphyxiation.