Hazardous Materials and the International Building Code: Part II
Last month’s blog discussed some of the basic requirements that sprinkler designers and code officials should be familiar with regarding the application of the model codes and hazardous materials. This month will focus on how to apply the maximum allowable quantities tables in the model codes.
Hazardous Materials: Storage, Use, or Both
The requirements outlined in the maximum allowable quantities’ tables in the International Fire Code (IFC) are based on if the hazardous materials are being stored or used. The IFC criteria is based on storage vs. use-closed system vs. use-open system. A closed system is where the product is in motion or being used or handled and the vapors from the product(s) are not exposed to the building atmosphere. Open systems are defined as the product is being used or handled and the vapors are exposed to the building atmosphere. Use of hazardous materials in an open system have the most restrictive requirements because it presents the greatest hazard to the building occupants and emergency personnel.
IFC Table 5003.1.1(1) Footnote D
The footnotes to Table 5003.1.1.(1) are important to read, understand and apply. Footnote d allows a 100% increase in the maximum allowable quantity when the building is protected throughout with an approved automatic sprinkler system. In this case, “approved” is defined as an automatic sprinkler system installed to NFPA 13. Automatic sprinkler systems installed pursuant to NFPA 13R (or 13D) are not granted the same increase in quantities as sprinkler systems installed to NFPA 13.
IFC Table 5003.1.1(1) Footnote E
Footnote E allows a 100% increase when the hazardous materials are stored in an approved hazardous materials storage cabinet that meets the requirements outlined in Section 5003.8.7.
The 100% increases for an automatic sprinkler system and storage cabinet are intended to be applied cumulatively. For example, if a business is storing gasoline (Class IB flammable liquid), Table 5003.1.1(1) allows up to 120 gallons in the building. If the building is protected throughout with an automatic sprinkler system (NFPA 13) and stored in approved hazardous materials storage cabinet, the MAQ is increased to 480 gallons per control area (120 gallons + 120 for sprinklers=240 gallons + 240 for storage cabinets= 480 gallons). The codes allow up to four control areas on the main level of a building when each control area is separated by minimum 1-hour fire resistive construction.
Multiple uses in the same building
It’s very common for a business to store and use (open or closed system) hazardous materials at the same time. For these situations, Footnote b in the IFC tables will apply. This footnote indicates the aggregate quantity in use and in storage cannot exceed the MAQ allowed for storage. This means when a business is using hazardous materials in an open or closed system and storing it elsewhere in the building, the MAQ for storage can never be exceeded.
Correctly determining the type and class of hazardous material being used is half the battle when applying the code requirements. After the type and class of material has been determined, simply follow the appropriate table in the IFC for physical or health hazard and indoor vs. outdoor control area to determine the requirements. Finally, be sure to consult with the building owner to determine how the hazardous materials will be used (storage vs. use in a closed system vs. use in an open system).
The National Fire Sprinkler Association’s (NFSA) Codes, Standards and Public Fire Protection Team is the best resource for all codes and standard updates surrounding fire protection. Team members sit on numerous NFPA technical committees and vote on changes that create a safer world. For more information on the NFSA, or to become a member of our association, visit our membership page.