Commercial Building Inspector B2Public Safety and Special ConstructionMedium
A building inspector is evaluating the fire protection system for a new Group A-2 assembly building with an occupant load of 400. The building is equipped with an automatic sprinkler system throughout. What is the minimum required fire-resistance rating for the fire barrier separating the main assembly space from an adjacent storage room (less than 100 sq ft) that contains ordinary combustibles?
- A1-hour
- B4-hour
- C2-hour
- D3-hour
Show answer & explanationAnswer & explanation
Correct answer: A. 1-hour
According to IBC Table 707.3.10, a fire barrier separating an incidental use area (such as a storage room less than 100 sq ft with ordinary combustibles) from a Group A-2 occupancy requires a 1-hour fire-resistance rating. The presence of an automatic sprinkler system does not reduce this specific rating for incidental use areas.
Why the other options are wrong
- B. 4-hour ratings are reserved for extreme hazard separations or fire walls between buildings.
- C. 2-hour ratings are typically for more hazardous separations or larger incidental uses.
- D. 3-hour ratings are for very high hazard separations or specific building types.
Incidental Use Fire Barrier
A fire barrier used to separate incidental accessory occupancies (e.g., small storage rooms) from the main occupancy.
- Required to be fire-resistance rated.
- Rating depends on the hazard and main occupancy.
- IBC Table 707.3.10 provides specific ratings.
Memory trick: Incidental storage? Check the table, rate the wall, keep the fire small.