Back in 2013, I wreote a couple of blog posts about placards on freight cars. The first of the posts was about prototype placards, with a number of examples (see it at: http://modelingthesp.blogspot.com/2013/11/placards-for-house-cars-prototype.html ). That was followed by a post about ways to model these placards, primarily showing application to model cars (it’s at this link: http://modelingthesp.blogspot.com/2013/11/placards-for-house-cars-modeling.html ).
An important use of placards is for hazardous cargoes, particularly in tank cars. I have written separate posts concentrating on the tank car part of the topic, beginning, again, with the prototype (this post can be found at: http://modelingthesp.blogspot.com/2012/03/tank-car-placards-prototype.html ). And here again, I followed with a post about modeling approaches, which is one way to show that a closed model tank car is in fact loaded or empty (read that post at: http://modelingthesp.blogspot.com/2012/12/tank-car-placards-more-on-modeling.html ). I mention this for completeness, since the present post is only about tank cars in passing.
One example of my topic is the placards used for refrigerator cars when car heaters were placed in the ice bunkers (obviously in sub-freezing weather). Whether the heaters burned charcoal or a liquid fuel like alcohol, there was a tendency to consume a lot of the oxygen in the car, so that continued combustion began to produce carbon monoxide, a deadly poison because it can’t be seen or smelled. The required placard on car doors (sent to me by Bill Jolitz) looked like this:
Those who model territories that might include operation of reefers with heaters on board could easily reduce a placard like this to HO scale size and place on some cars.
Most of us are familiar with the idea that some boxcar cargoes were loaded in a way that blocked one of the side doors, so that the car had to be placarded (on each side) to inform crews of this fact. Then they could correctly orient a car for spotting at the consignee. Naturally one side would have a placard saying “Unload This Side,” and the other side’s placard would read “Unload Other Side.” These were supplied by each individual railroad to its shippers. Here is a Southern Pacific example.
Note that this placard is yellow, though many were manila in color. This one is from my own collection. Here’s an example of the one that might be on the other side:
There were also a variety of diamond-shaped placards. We normally associate these with tank cars, where the diamond shape was standard. But these diamond placards could also be used on house cars with certain kinds of cargoes, not only flammable or otherwise dangerous cargoes, but also fragile ones. This example from the Nickel Plate shows what I mean; the original is 8.5 inches square, smaller than a standard 10.5-inch tank car placard. (You can click to enlarge, to read the small print.)