NFPA 498-2018 Standard for Safe Havens and Interchange Lots for Vehicles Transporting Explosives.
5.1.1* Temporary Holding Facility. Δ 126.96.36.199 A temporary holding facility conforming to the construction requirements for Type 1 or Type 2 magazines as described in NFPA 495 shall be provided in the interchange lot. 188.8.131.52 If detonators or other initiators are to be temporarily held at the same time as other explosives, then two temporary holding facilities shall be required: one for detonators (initia‐ tors) and the second for the other explosives. 5.1.2 The facilities specifed in 5.1.1 shall be located a mini‐ mum of 15.3 m (50 ft) from structures on the adjoining prop‐ erty or any facility that could create a fre hazard. 5.1.3 Where an area at the loading dock is designated for the temporary holding of explosives in a trailer (as provided in Section 5.2), it shall not be located within 15.3 m (50 ft) of a fre hazard such as an area where smoking is permitted, hot work is being done, or combustible or fammable materials are present. 5.2 Operations. 5.2.1 Explosives brought into the interchange lot to await shipment shall be immediately placed in the facility specifed in 5.1.1 until such time as the explosives are loaded on a depart‐ ing over-the-road motor vehicle. 5.2.2 Explosives delivered to the interchange lot by a connect‐ ing carrier shall be retained in the trailer at a designated section of the loading dock, or the trailer shall be parked in an isolated area of the interchange lot, or the explosives shall be placed in the holding facility. 5.2.3 The explosives transport vehicles, including trailers, in the interchange lot shall be maintained in the same condition as is required for highway transportation, including placarding. 5.2.4 Explosives shall not be retained on the lot, either in a trailer or holding facility, for a period longer than necessary, but in no case for more than 100 hours.
5.2.5 Smoking, matches, open fames, spark-producing devi‐ ces, and frearms shall be prohibited inside and within 15.3 m (50 ft) of the temporary holding facility or trailer containing explosives unless otherwise permitted in 5.2.6. 5.2.6 Law enforcement and security personnel shall be permit‐ ted to carry frearms where specifcally authorized by the authority having jurisdiction. 5.2.7 Temporary facilities as specifed in 5.1.1 shall be appro‐ priately marked so that the interchange lot employees are aware of the location. 5.2.8 At least two portable fre extinguishers, having a capacity of at least 4-A:40-B:C, shall be placed at each temporary hold‐ ing facility and shall be readily available for immediate use. 5.2.9 Employee Training at Interchange Lots. The operator of the explosives motor vehicle interchange lot shall maintain an active training program in emergency procedures for all employees stationed at the interchange lot.NFPA 498 pdf download.