Fire Alarm Design Program for Incidental Use Occupancy

Fire Alarm Design Program for Incidental Use Occupancy
Anthony Conte
Latest posts by Anthony Conte (see all)

For fire alarm designers, electrical engineers and other contractors, it is crucial to know the building occupancy classifications of the National Fire Protection Association (NFPA) and other nationally and internationally recognized building and fire codes. Occupancy classifications are an important part of applying both the NFPA 101 Life Safety Code and the International Building Code (IBC) to any space. There are many occupancy classifications, from assembly, to educational, to health care and more. In addition to these, there is an ancillary classification that fire alarm designers should be aware of: incidental use occupancy. 

What is Incidental Use Occupancy?

Incidental use occupancy has at least two different definitions, depending on which code is being applied. 

For NFPA 101

The NFPA defines incidental as occupancy for minor uses that support the predominant occupancy. Because the uses are considered minor, they do not warrant their own occupancy classification — and as such, the space is deemed \”incidental use occupancy.\” Often, an incidental use occupancy may be for an outbuilding or other accessory space to a larger primary building. 


Incidental occupancy by the NFPA’s definition has a different name within International Building Code. The IBC calls these minor use spaces \”accessory occupancies.\” However, IBC also uses the term \”incidental\” — but for a different purpose. IBC defines incidental occupancies as hazardous areas for occupancy.

Examples may include furnace rooms, boiler rooms, incinerator rooms, or paint shops. 

Call Cadgen for More Support 

By knowing the definitions of incidental use occupancy, fire alarm designers, electrical engineers and other stakeholders can create more precise fire protection designs that adequately serve the needs of the space they are working with. If you are in need of a fire alarm design program for incidental use occupancy, consider FireCAD™, a fire alarm design program from Cadgen. We offer both a lifetime license and flexible subscription options. Please contact our sales department at (855) 206-1480 Ext. 1 to learn more; they will be glad to assist you.    

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