This sign is at Martinez on the UP (former SP) right-of-way, presumably to keep 911 calls for a “runaway” train to a minimum. Immediately west of Martinez is the pocket-sized Ozol yard (which replaced the Port Costa yard in 1960.)
Common for switch engines to be equipped with remote control equipment so they can be controlled by the guy on the ground.
I have seen a similar sign near the UP yard in Portland, Or right near a road crossing. Like you said, to keep people from freaking and hopefully watching out for trains as well.
It probably has less to do with 9-1-1 runaway trains calls, and more to remind people that there’s no one in the cab that can apply the brakes. If they’re standing on the track and the person operating the engine by remote can’t see them, they’re going to get run over.
Oh boy, can you image the guy that just saw the movie Unstoppable, that doesn’t see the sign. Now that would be funny to see.
guy - “OMG! OMG! there is a runaway train, you need to stop it before it gets to the next town and derails on the curved trestle bridge!!!, do you have an engine to catch it?”
dispatcher/police - “calm down sir, this is not a movie”.
we should have had warning signs that the crew may be drunk or asleep.
grizlump