If you want to design a tartan for firefighters, or find a way to have the word spread about the existing one, I would suggest you contact the IAFF. I'm sure they would print an article about it in their paper. If you had a kilt made in that tartan you might also get your picture in there.

Also, many departments have their of Gaelic brigades. Perhaps you could contact some of them. Don't they have a big get toghether every year?