An SPL meter cannot tell you where the sound is coming from.
It can kinda get close if you are lucky-but it could also be reading reflections, which can really screw with what it is telling you.
Oh yeah I understand that walking around with a db meter can't possibly give anything close to the level of precision that the Acoustic Camera would give. I guess I should have said that in terms of the whole building, db meters have shown that the emergency exit door is the only major problem - and currently, it's a huge mess of a problem that the precision of the Acoustic Camera would likely be wasted on. Once the door is replaced, the wall around it is reinforced or replaced, and the seal between the door and it's frame are tight, we'll see where we're at. If we're still having issues, I'd think that would be the time that the Acoustic Camera would be most useful?