Andrew Pollack's Blog

Technology, Family, Entertainment, Politics, and Random Noise

First Beijing train reaches Lhasa -- Why Oxygen on it? That makes no sense to me. The problem at elevation isn't the oxygen.

By Andrew Pollack on 07/03/2006 at 09:20 PM EDT

So this train goes from Beijing to Lhasa -- covering permafrost and mountains. It peaks over 16,000 feet. I've been as high as 12,000 feet and hiked around a bit without getting too tired, but I was younger and I'd imagine that extra altitude could really do a person in. So, the Chinese built the train with onboard oxygen. This makes no sense to me.

The problem at altitude isn't lake of oxygen per se. Its lack of pressure. The amount of oxygen as a percentage is the same, but with reduced pressure, less is able to cross the membrane in our lungs and get into the bloodstream. (reference). On airplanes at 40,000 feet they are not pumping oxygen into the cabin. The will do so in an emergency only if the plane cannot contain cabin pressure. Why do you suppose that is? Does it cost less? No. The issue is that it doesn't help as much, and at the same time oxygen is very dangerous stuff. A few percent more than normal and something as innocent as a cigarette lighter can become a real problem. It is corrosive (it is, after all, an oxidizer) and highly flammable.

What I don't get then, is why go to the expense of adding oxygen distribution equipment to the train like that rather than simply pressurizing the cabin? If not everyone needs it, perhaps just pressurize a few cabins -- or provide a pressure mask for positive pressure breathing.

Someone who's seen a documentary on this strange train should post a comment and clue me in.

http://news.bbc.co.uk/2/hi/asia-pacific/5140514.stm


There are  - loading -  comments....

I would guess it's a matter of economicsBy Richard Schwartz on 07/04/2006 at 12:35 AM EDT
I would guess that the train is at a low enough altitude most of the time that
neither 02 nor pressurized cabin is needed. A system capable of delivering 02
for the periods of time that the train is at high enough altitude to need it is
readily available. Railroad cars with pressurized cabins would have to be
specially designed, built, and maintained.
methinksBy Craig Wiseman on 07/05/2006 at 10:35 PM EDT
The fireman is thinking about how much damage an O2 leak could do.....

Poof! goodbye train....
From all accounts, oxigen was the least of their problems!By Ian Randall on 07/09/2006 at 06:45 PM EDT
I recollect recently hearing a National Geographic story on the building of
this rail line.

Apparently a great many (several hundred) workers involved in constructing of
the Beijing to Lhasa rail line lost their lives.

But then, it's construction was motivated more by public relations and military
objectives more than than tourism , so the massive loss of life was probably
justified as an acceptible cost by the Chinese Government.

Also, it's construction bolsters the Chinese Governments claims of soverenty
over Tibet, so no cost would have been seen as too high.
OxygenBy brianorca on 07/13/2006 at 05:26 PM EDT
Oxygen actually is the problem with low pressure. We need a "partial pressure"
of 3psi of oxygen to breath. That can be in the form of 20% of the 15psi we get
at sea level, or 40% of the 8psi you might find at 14,000 ft. The astronauts,
when wearing a space suit, actually breath pure oxygen at only 4.5psi.

3psi of oxygen is not any more flamable than the mix we breath at sea level.

The previous poster also had some good points about the technical requirements
(hardware and maintenance) of a presurized train.


Other Recent Stories...

  1. 05/05/2016Is the growing social-sourced economy the modern back door into socialism?Is the growing social-sourced economy the modern back door into socialism? I read a really insightful post a couple of days ago that suggested the use of social network funding sites like “Go Fund Me” and “Kickstarter” have come about and gained popularity in part because the existing economy in no longer serving its purpose for anyone who isn’t already wealthy. Have the traditional ways to get new ventures funded become closed to all but a few who aren’t already connected to them and so onerous as to make ...... 
  2. 04/20/2016Want to be whitelisted? Here are some sensible rules for web site advertisingAn increasing number of websites are now detecting when users have ad-blocking enabled, and refuse to show content unless you "whitelist" their site (disable your ad-blocking for them). I think that is a fair decision on their part, it's how they pay for the site. However, if you want me (and many others) to white list your site, there are some rules you should follow. If you violate these rules, I won't whitelist your site, I'll just find content elsewhere. 1. The total space taken up by advertisements ...... 
  3. 12/30/2015Fantastic new series on Syfy called “The Expanse” – for people who love traditional science fiction[] “The Expanse” is a new science fiction series being broadcast onthe Syfy channelthis winter. It’s closely based on a series of books by author James S. A. Corey beginning with “Leviathan Wakes”. There are 5 books in the “Expanse” series so far. If you’re a fan of the novels you’ll appreciate how closely the books are followed.TIP: The first five episodes are already available on Syfy.com. If you’re having trouble getting into the characters and plot, use those to get up to speed.The worlds created for ...... 
  4. 10/20/2015My suggestion is to stay away from PayAnywhere(dot)com  
  5. 08/07/2015Here is one for you VMWARE gurus - particularly if you run ESXi without fancy drive arrays 
  6. 08/06/2015The Killer of Orphans (Orphan Documents) 
  7. 06/02/2015Homeopathic Marketing: Traveler on my Android is now calling itself VERSE. Allow me to translate that for the IBM Notes community... 
  8. 03/17/2015A review of British Airways Premium Economy Service – How to destroy customer goodwill all at once 
  9. 02/26/2015There's a bug in how @TextToTime() and @ToTime() process date strings related to international standards and browser settings. 
  10. 01/21/2015Delivering two new presentations at Developer Camp (EntwicklerCamp) 2015 in Germany 
Click here for more articles.....


pen icon Comment Entry
Subject
Your Name
Homepage
*Your Email
* Your email address is required, but not displayed.
 
Your thoughts....
 
Remember Me  

Please wait while your document is saved.