Maybe it would be worthwhile to find a way to incorporate the number of lives saved by his department since he began working as a firefighter. Like maybe on the border you could have one small star for every life.

I like kaelynangelfoot's idea -- lives saved, number of responses, cities/counties of operation .... You could incorporate some of those statistics things. Does the department have a motto? You might be able to incorporate that, too.

The first thing I thought of when I read your post was narrow chevrons.