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. 10/08/2018Will you be at the NYC Launch Event for HCL Domino v10 -- Find me!Come find me in NYC on Wednesday at the Launch Event if you're there. I really do want to talk to ...... 
  2. 09/04/2018With two big projects on hold, I suddenly find myself very available for new short and long term projects. In twenty five years, I don't think I've ever written an entry like this, but if you need the kind of work I do now would be a great time to get in touch. Both of the big projects I had lined up for late summer and early fall have been placed on hold and will be that way for a while. With the kids now all off at college and careers, I'm open to more travel than such than I have been in decades, but unless something else comes along, I'll be here working on updates to Second Signal and other things that ...... 
  3. 07/13/2018Who is HCL and why is it a good thing that they are now the ones behind Notes and Domino?We need to address some biases here. IBM has made a deal under which the Notes & Domino software and intellectual property is now being developed and maintained by HCL America. HCL America is part of the very large "HCL Technologies" company that has grown from its roots in India to become an 8 Billion Dollar company with a global presence in the IT Industry. You could be excused for initially believing, as many people do when they hear this, that "they've outsourced the code to India where they'll milk it ...... 
  4. 03/21/2018Domino Apps on IOS is a Game Changer. Quit holding back. 
  5. 02/15/2018Andrew’s Proposed Gun Laws 
  6. 05/05/2016Is the growing social-sourced economy the modern back door into socialism? 
  7. 04/20/2016Want to be whitelisted? Here are some sensible rules for web site advertising 
  8. 12/30/2015Fantastic new series on Syfy called “The Expanse” – for people who love traditional science fiction 
  9. 10/20/2015My suggestion is to stay away from PayAnywhere(dot)com  
  10. 08/07/2015Here is one for you VMWARE gurus - particularly if you run ESXi without fancy drive arrays 
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.