My department has a very clear policy on firearms that is all of 1 paragraph = NO
This is about how it goes IIRC - No firearms are allowed on any department property. Any violation will result in significant disciplinary action.
I have thought about this often as we go into several high crime areas with highrise apartment buildings in which our radios don't work reliably. So no mayday calls. We often go into the areas for water leaks, medicals (often turn out to be domestics), calls for the smell of gas etc, and find ourselves out numbered, in gang houses or other bad places. People that don't want PD in thier homes or other places, have figured out how to call for help in a way which police will not come, but fire and EMS will. It would be impossible for the police to come with us on every call given our call volume and thier's.
So if it was allowed, I certainly would CCW. But I can't afford to loose my job and there is literally no way to CCW without someone finding out. Bringing an axe to a gunfight, well you know how that would work out!!
Obviously, like my cell phone and wallet, If we were allowed to CCW on-duty, we would need a secure place to store it during fire suppression.