How are occupancy use category and hazard classification related?

The concept of occupancy use category and hazard classification is interconnected, but they are not necessarily the same or directly dependent on each other. Occupancy use categories refer to the purpose for which a building or space is used, such as residential, commercial, industrial, or assembly. These categories help in defining the expected human activity and the associated level of risk.

On the other hand, hazard classification deals with the specific risks present within that occupancy, such as the types and amounts of combustible materials, flammable liquids, or processes that may cause fire hazards. While certain occupancy categories might commonly align with higher or lower hazards, this relationship is not absolute.

For example, a building could be classified as residential, which typically entails lower hazards, but if it includes a garage with substantial flammable materials, the hazard classification could be elevated even though the primary occupancy remains residential. Conversely, an industrial facility might have low hazards if well-managed and equipped with safety features.

Thus, the two concepts serve different purposes in fire safety and building codes, establishing that they are not simply synonymous, and occupancy does not solely determine hazard classification. Each should be assessed independently to understand the overall fire risk of a structure.