I'm trying to remember the layout of the Atlanta airport but all the airports I've been to blur together in my mind - except for Atlanta's cool elevated tram.

Are you saying that the firefighter bought one of Doug's Personal Survival Paks at an airport behind (after) the security check?

That makes no sense to me since the PSP contains a scalpel. Maybe the store was before security. Did the firefighter have to remove the scalpel before boarding the plane?