Being a Firefighter is like being a Cop, you can pretty much go in, flash your badge, and start the chatting...its like being in a fraternity, I belong to one and I have friends anywhere in the world I go. Its really a nice feeling, specially if I end up in trouble of some sort. If I were you I would not hesitate to go and visit firehalls in Europe, share stories, techniques, and interests. Chances are you will going out for drinks with the ladies and gentleman in red. As for being a "military related" outfit...I would not care, do it anyway!
Here are couple links for ya that might help you connect with some of your collegues...
Irish Fire Service
Firefighters Meet Up I know you will not be there for this, as it happens in a few days, BUT, great place to link up with some others.
And this one is great...
World Fire Departments
I hope these help help ya out, and thanks for being there when we need help!!!
And I would like to give you a big Travelpunk