LEUP and day boxes

I'm working through the process of getting my LEUP and had a very good meeting with one of our local ATF personnel, Inspector Nora Mace, the other day.
A question came up that we had no answer for about the use of type 3 magazines, or "Day Boxes", and the labeling requirements of the magazine. She contacted the Charlotte Fire Inspector's office and made some inquiries on our behalf and I thought I'd share what we found.
From the NFPA code, adopted by both North Carolina and Charlotte/Mecklenburg:
Day Boxes
National Fire Protection Association (NFPA) 495 Above ground storage of Explosive Materials
9.6.3 Type 3 Magazines: A type 3 magazine shall be a "day box" or portable structure used for the temporary storage of explosive materials.
9.6.3.6 Type 3 magazines containing explosive materials shall be within line of site vision of a blaster.
On the question of to mark or not mark a day box with the word �Explosives�: Deputy Fire Marshal Leonard stated there does not appear to be any requirement for labeling or marking. The local ATF office does support labeling of type 3 magazines as "good practice".
So while it's not a MUST, it does seem like it might be appropriate. Our concern was one of calling attention to what the contents of the magazine might be to someone who would find it attractive to steal, vs. the need to alert personnel in the event of a fire or other emergency response situation.