I keep a few firearms and a LOT of ammo in my home (just a side effect of my job), and at work we use different signs to let DoD fire departments know what hazards are in buildings. I live outside of that area, and local FD responds to incidents in this area. I'm gonna guess that local FDs and federal FDs use different markers for fire/explosive hazards, or do they? What placard would I use to let responding firefighters know that there are a lot of munitions in my home? (If it helps, DoD uses this kind of sign for what I would need http://www.compliancesigns.com/DOD-004.shtml) @Sensible_man: There are currently no limits to quantities of ammunition that are allowed to be stored in residences, via BATFE (besides, as a federal law enforcement official, I'm pretty sure I could write these off as work-related). There are limits to how much smokeless powder one may store in their residences, but none for loaded ammunition. And I wouldn't be asking if I knew the form in which to advise the local department.