Things You'll Need
Instructions
Remove all light sources, such as lamps, windows and doors, in the room where you will perform the test.
Turn on the UV black light device.
Shine the light over the three decals: the old decal, the modern decal and the one being tested. The modern decal should fluoresce brightly. The old decal should not glow.
Compare the decal being tested to the other two. If the decal being tested is an original, it should not glow like the old decal.