I talked with my dad about it (retired firefighter, so he has contacts and sources), and he says it isnt actually new, they have just had to step it up. But they have been having to wear vest for years now. Same with a lot of major cities. Another one I know of (because there was a family story involving it) is that in Atlanta they have a cage over the parking lot of where they keep the trucks. Because even keeping them locked up in the building is no guarantee they wont get stolen or broken into. Yes, you heard that right, there are gang bangers trying to steal fire trucks because "reasons beyond your comprehension as a sane person."