NFPA 58, the LP-Gas Code, uses the term "important building" when stating where an LP-Gas container may be placed. An important building is defined in section 3.3.38 of the code as “A building that is considered not expendable in an exposure fire”.  In North Carolina, if any one of the following situations exists, the building is “important”:

• Human occupancy
• Replacement value
• Value of the building contents
• Vital role of its production equipment or business records to a business
• The effect of building location on LP-gas release and fire control activities by firefighters and other emergency responders
• The building is made of combustible material or contains combustible material.
• The building contains a source of ignition.

Furthermore, if a building is locked or it or its contents are insured against theft, fire, or natural disaster it is an important building.