What's next? No Breathing?

Today I was out and about on one of my weekly fact-finding runs when I came across this sign stenciled onto the side of a circa 1935 Union Pacific Railroad Passenger Car. Surprising to some, I would imagine, this sign was not spotted in Tooele County. I found this gem on a railroad siding in Evanston, Wyoming.
I was wondering who was responsible for this most intriguing regulation and I came up with the following possibilities.

1.. As it was on a railroad car, perhaps the railroad was responsible. I know that too much swaying of a railroad car from side-to-side cause uneven wear on the rails and ties and thus increases maintenance costs. So it would be in the railroads best interests to put a halt to any unnecessary movement in the rail cars.

2. Perhaps the government is behind this. They have been known to use advertising to promote some programs they are behind. I.E. Smokey the Bear, anti-smoking, Baby-your-baby, slow the flow, etc. Now that the are realizing that free condoms in the middle and grade schools aren't working they could be doing a PR campaign for abstinence.

3. In the days prior to commercial air travel, all college football teams traveled by train. Perhaps this was a special Charter Car for the BYU Team.

4. Before the days of televangelists and television those spreading the good word would sometimes charter train cars for travel from motel to motel. I mean from city to city. I can almost see Jimmy Swaggart waving from the platform of this car to all the sinners across the country.

If any of you know the actual reason this is on this car, I will be rightly impressed. In all honesty don't think its any of the above reasons