I downloaded FDR’s Wartime Train Travels from the Classic Trains web site and ran across this in a sidebar describing B&O 1401, a combine pressed into service as a communications car :
… the AAR faulted [the White House Signal Detachment] for placing a gasoline tank below the frame of the car. AAR people directed that a double-walled tank with CO2 be used between the walls. This created its own problems, for each time the train neared a tunnel, it would have to stop so the CO2 tank could be emptied, and upon exiting, it would halt again so the tank could be refilled.
Why did the CO2 tank have to be empty while going through a tunnel (other than “because the AAR said so”)?
One thing that comes to mind is that some tunnels – the Holland and Lincoln tunnels being specific examples – have a blanket prohibition against ‘compressed gases’. There isn’t any exception for INERT compressed gases, and I believe this is intentional (the pressure bottles become shrapnel bombs in a fire).
Why such a premise would apply to railroad tunnels isn’t clear; perhaps there are people on here familiar with specific railroad policies who know. Wouldn’t surprise me to find a prohibition against pressurized gases on passenger cars, though…
Now, to call an inert-gas blanket a ‘pressure vessel’ in this context is right up there with calling a superheater with front-end throttle a ‘separately-fired’ pressure vessel. But those who were there at the time might have recognized something more significant, and I don’t want to second-guess them.
My guess would be a fear of a derailment or other accident that could trap the car in a tunnel already choking with coal smoke. Adding CO2 from a leaking tank caused by the derailment, to a tunnel already short of breathable air, wouldn’t be a good idea.
The restrictions on commpressed gases in tunnels only applies to flammable materials IIRC. And that prohibition has been since the 1970’s. The asphyxiating effect with CO2 should only a problem with large quantities I would think. I’m talking about in excess of 1000lbs. By the way did the car baggage car have a generator to provide electrical power? If it did the generator fuel tank may have been the problem not CO2. Rgds IGN
Carbon Dioxide was the problem, people breathing would have to be prevented.
Compressed CO2 was the problem, there’d be know way operate a seltzer water bottle, or to carry the replacement gas for the fuel tank blanket at the end of the tunnel.
Compressed flammable gas was the problem, what exempted SP’s many passenger car’s generators powered by Waukesha engines fueled with propane? 'never did like the smell of the exhaust from them.
It’s much less of a mystery than the fate of the 239 on board Flt. 370, but for mysterious quality…some equality.
Flt. 370…239 Souls On Board…Don’t abbreviate using the word’s first letter’s…I almost did.
Digression alert!!
No 51, San Joaquin Daylight, rollin’ on fast track from Fresno, Sunny and warm, highs near 103 F…Waukeshas conditioning air in the train…Boiler Failure alarms. Why?
Hot water to wash and sanitize dining car “stuff” and heat the “H” water in the lavatories.
People breathing in a ventilated area is not a problem, but breathing in a confined area with a large release from a pressurized CO2 tank could be a problem. The human body has a narrow tolerance range for oxygen levels. Air is about 21% oxygen, but when the level gets down to about 19% it’s life threatening.
