Not “sacrificial goat.”
The reason the phrase “sacrificial coat” uses the word “sacrificial” has absolutely nothing to do with burnt offerings, or mysterious gatherings in the deep woods late at night. Rather, it’s called “sacrificial” simply because it is a sacrificed coat.
It’s called a “coat” because it is like a coat of paint. Not because it is like a coat that you can wear (see below for example photos explaining differences).
Now that we have some basic semantics out of the way, here’s a better definition:
“A sacrificial coating forms a clear coat barrier over the wall or surface being protected. If the surface is vandalized the coating can be removed (sacrificed) using a high-pressure washer taking the graffiti with it. The coating then must be reapplied. The materials used to make a sacrificial coating are usually inexpensive optically clear polymers such as acrylates, biopolymers, and waxes. These polymers form weak bonds with the substrate to allow for easy removal.”
This type of coating is also more environmentally friendly.
“Sacrificial coatings have the advantage of being removable (hence “sacrificial”), and are therefore less controversial. The clean wall is treated so that future graffiti will come off easily when the coating itself is removed. At that point, a new coating would be applied. Wax-based protective coatings are much more sensitive to valuable surfaces than previous types of coatings or barrier methods. These coatings melt off with the use of high-powered sprays or hot water, taking the offensive graffiti with them. Wax-based coatings are unlikely to destroy nearby plant or wild life, as well. In addition, they allow the materials underneath to breathe, preventing decay of their surfaces.”
From pps.org. . . [Emphasis added]
Now you might be wondering why we are talking about all this sacrifice stuff. Well, we decided to start coating areas that get hit a lot with graffiti. Then when we need to clean graffiti, we don’t need to use harsh chemicals. We also don’t need to repaint. This is faster, simpler, and as mentioned above – much more environmentally friendly. In fact, we are using common floor wax as our coating. It’s inexpensive, durable, water-based, and non-toxic.
So as you can see, some sacrifices are good sacrifices! (And some coats are good coats).