Tunnels and train crews

[Murphy Siding]

      Some photos on another thread of MRL locomotives that are black from use in tunnels make me wonder. I've read where SP had issues with smoke in tunnels, leading to cab forward steam locomotives. I think I recall some steam era railroads putting gas masks on their crews? In modern times, are there any safety issues with rail crews and tunnels?

[BEAUSABRE]

Murphy Siding

I think I recall some steam era railroads putting gas masks on their crews?

Yep, air from the brake system passed through a reducer valve to supply a mask. Here's the Southern's version - almost assuredly on the "Rathole" line (CNO&TP)

[NDG]

SP 4193.

 

On November 11, 1941, SP 4193 slipped to a Stop in Hasson Tunnel,

got a knuckle way back and smoke filled the Bore.

 

Five 5 died.

 

Oil Fire warped track and locomotive frame. 

 

https://en.wikipedia.org/wiki/Southern_Pacific_class_AC-8

 

Accident report on Internet.

 

S.P. Company.

 

I.C.C. Investigation No. 2543.

 

Near Hasson, California, November 19, 1941.

 

 

Thank You.

 

P.S.  Was there not a Head On just outside the Tunnel here btwn a Commuter Train and a UP Freight a few years ago w large loss of life?

 

 

[Euclid]

Were they breathing air directly from the brake system without any special extra filtering?

[samfp1943]

""TUNNEL MOTORS":  Bporn originall of Sothern Pacific rr Heritage, and still 'seeded' in current railroad usage....After fourty plus years, spread like crab grass after the railroad game of merger's and Buy -me, and live forever?

Here is a link from a past TRAINS  Article @ https://www.trains.com/trn/train-basics/abcs-of-railroading/tunnel-motors-from-the-past/

They have 'sprouted' all over... Canadian National, and Feromex to name a couple of odd ones...

Here's a C&P,m from the linked article:

"...Eventually, the tunnel motors built for Southern Pacific and Rio Grande and still on the roster in 1996 ended up in the employ of Union Pacific. The majority of the tunnel motors were purged from UP’s roster in the 2000s, ending up on dozens of other Class I railroads, short lines, regionals, and lease fleets across North America. Canadian National is the only Class I operating the tunnel-motor design today. It inherited two separate fleets of SD45T-2s (rebuilt mechanically to SD40-3s) during its acquisition of Bessemer & Lake Erie in 2004 and Duluth, Missabe & Iron Range in 2011. Its fleet of 20 tunnel motors see service primarily on CN’s iron-ore operations in the upper Midwest..."

 

 

[PNWRMNM]

Murphy Siding

      In modern times, are there any safety issues with rail crews and tunnels?

Murphy,

Yes. BNSF Cascade Subdivision Special Instructions contain several paragraphs about use of Breathing Apparatus in the 7.79 mile long Cascade Tunnel. I suspect same is true at their Flathead Tunnel in Montana. These apply in emergecy situations when a crewman has to be on the ground in the tunnel.

There is nothing special for normal operations because ascending eastward trains are working against strong winds created by the ventilation system. Westward trains run on dynamic brake which do not need nearly the air flow to operate as do ascending trains under power. Cascade Tunnel grade is 1.57% ascending eastward. I do not know what the grade in Flathead Tunnel is.

Mac

[Bruce Kelly]

Eastward ascending grade in Flathead Tunnel is 0.46%.

BNSF crews who operate through the Cascade, Flathead, and Stampede tunnels are trained in the use of and instructed to carry with them Emergency Escape Breathing Apparatus, as it's called in the employee timetable.

 

[Overmod]

PNWRMNM

I do not know what the grade in Flathead Tunnel is.

https://www.jstor.org/stable/44565540

If anyone has trouble accessing relevant sections of this, let me know.

(Didn't Flying Scotsman go through this tunnel, with no particular bad effects, shortly after it was completed?  ISTR a Trains article with details...)

[BEAUSABRE]

Euclid

Were they breathing air directly from the brake system without any special extra filtering? 

So far as I know yes. Not sure why the air would need to be filtered any more than normal brake air - the air compressors had "strainers" on them to keep out dirt, etc. This is a drawing of a cross compound air compressor - the air strainer is the "can" on the right

If you are woried about gas and smoke drawn into the system, it would be diuted by the air already in the tanks and the compressor would not necessaily be running in the tunnels, only when the supply of compressed air needed to be topped off. 

Aa I stated, a pressure reducing valve was used to reduce pressure to the hood to slightly above atmospheric (if there were any leaks, the air would flow outwards instead of allowing contaminated air in, The same principle as the modern "sealed carbody" locomotive as introduced by GE in the U25B circa 1960)

[Murphy Siding]

Bruce Kelly

Eastward ascending grade in Flathead Tunnel is 0.46%.

BNSF crews who operate through the Cascade, Flathead, and Stampede tunnels are trained in the use of and instructed to carry with them Emergency Escape Breathing Apparatus, as it's called in the employee timetable.

 

 

So that's to allow them to get out of a smoky tunnel in an emergency? What about the everyday business of running a locomotive through a tunnel? Do they have to worry about breathing in smoke there, or is it just a matter of rolling up the windows? (Yes, I know they probably don't roll up.)

[Euclid]

BEAUSABRE

 

 

Euclid

Were they breathing air directly from the brake system without any special extra filtering? 

 

 

So far as I know yes. Not sure why the air would need to be filtered any more than normal brake air - the air compressors had "strainers" on them to keep out dirt, etc. This is a drawing of a cross compound air compressor - the air strainer is the "can" on the right

If you are woried about gas and smoke drawn into the system, it would be diuted by the air already in the tanks and the compressor would not necessaily be running in the tunnels, only when the supply of compressed air needed to be topped off. 

Aa I stated, a pressure reducing valve was used to reduce pressure to the hood to slightly above atmospheric (if there were any leaks, the air would flow outwards instead of allowing contaminated air in, The same principle as the modern "sealed carbody" locomotive as introduced by GE in the U25B circa 1960)

 

Thanks for that information.  I was thinking about the issue of compressor lubrication introducing oil into the compressed air.  I know that when SCUBA sport diving became popular, there was an interest by divers in doing their own recharge of their tanks.   A big issue emerged over the need to have an oil-free compressor for air that was intended to be breathed.  The amount of oil was relatively very small, in the form of vapor, but for breathing, it was a health hazard.  For compressed air not for breathing, the oil was not a problem.  It could be used for inflating tires or running pneumatic hammers, etc.  

 

So for most uses, oil lubricated compressors are okay.  But for SCUBA bottles, it requires air from an oil-free compressor or an array of specialized filters and separators adequate to remove all of the oil in the compressed air.  So I was just wondering how that would apply to locomotive engineers breathing compressed air from the brake compressor.  How are those steam locomotive air pumps lubricated on the steam pump side and the air compressor side? 

[Convicted One]

Euclid

So I was just wondering how that would apply to locomotive engineers breathing compressed air from the brake compressor

Didn't they use asbestos canisters to filter out the oil during the pre-OSHA  era?  

[dpeltier]

Murphy Siding

So that's to allow them to get out of a smoky tunnel in an emergency? What about the everyday business of running a locomotive through a tunnel? Do they have to worry about breathing in smoke there, or is it just a matter of rolling up the windows? (Yes, I know they probably don't roll up.)

Correct, the SCUBA gear is for if you have to walk out of the tunnel. There are tanks stashed every so often in niches in the tunnel wall for when the air runs out in one.

In normal operations, the ventilation system does a pretty good job of keeping exhaust gases out of the cab. Thomas White has a web page explaining how the ventilation system works specifically in the Cascade Tunnel: http://dslweb.nwnexus.com/tawhite/CASCADE%20TUNNEL.html

Dan

[tree68]

SCUBA (and SCBA, for firefighters, etc) air is tested periodically.  Our fire department fills SCUBA tanks as well as firefighting tanks, so the air meets the required standard.

SCBA is now available that will last an hour under normal use.  The rule of thumb for firefighting is that a half hour tank will probably last just 20 minutes.  The hour rated packs are generally used for HazMat, where just suiting up and undressing can take a fair amount of time.   The tank pressure is on the order of 4,500 PSI.

Firefighters have to be medically cleared for SCBA, including a spirometer (tests lung volume), as well as an annual mask fit test.

[mvlandsw]

  It's an interesting experience to be crawling upgrade at full throttle and slow speed in a tunnel while watching the exhaust smoke slowly descend from the roof to the track.

B&O instructions were to cut off the engine and exit the tunnel if the train stalled. No special equipment was provide in the diesel days.