In which scenario might a building not require occupant separation according to NFPA 101?

The scenario where a building might not require occupant separation according to NFPA 101 is when it is a mixed occupancy. NFPA 101, also known as the Life Safety Code, has specific provisions regarding the separation of different occupancy types to ensure safety during emergencies. However, if a mixed occupancy building is designed and constructed in a manner that adequately protects all occupants and meets other code requirements, it may not necessitate strict occupant separation.

This situation typically arises in buildings where the separation is either not required due to the size and use of each space or where the risks of one occupancy do not adversely affect the other. Proper design, fire protection systems, and occupancy limitations can allow for more flexible arrangements that do not strictly enforce separation, thus enhancing practical use of space while still adhering to safety standards.

The other scenarios presented do not align with situations that preclude the need for occupant separation. Local codes being congruent does not eliminate the requirements set forth in NFPA 101. A fully residential building often still requires consideration for occupant safety and may necessitate certain fire protection measures. Similarly, a building under inspection would still need to comply with occupant separation requirements unless it meets specific criteria outlined in the life safety code.