For exemption, unprotected ceiling pocket volume must not exceed?

For exemption, unprotected ceiling pocket volume must not exceed?

• A. 50 ft3
• B. 100 ft3
• C. 150 ft3
• D. 200 ft3

Answer: (B)

Unprotected ceiling pockets can be left without sprinklers if the pocket is small enough. In NFPA 13R for low-rise residences, the exemption applies when the volume of the ceiling pocket is not more than 100 cubic feet. The reason is that a very small pocket doesn’t store enough heat or fuel to significantly affect fire growth or water distribution, so providing sprinklers inside that pocket isn’t necessary while still protecting occupants in the rest of the space. The pocket volume is measured for each individual pocket (space between the suspended ceiling and the structural ceiling), and if any pocket exceeds 100 ft^3, that exemption doesn’t apply to it and sprinklers would be required there.

Unprotected ceiling pockets can be left without sprinklers if the pocket is small enough. In NFPA 13R for low-rise residences, the exemption applies when the volume of the ceiling pocket is not more than 100 cubic feet. The reason is that a very small pocket doesn’t store enough heat or fuel to significantly affect fire growth or water distribution, so providing sprinklers inside that pocket isn’t necessary while still protecting occupants in the rest of the space. The pocket volume is measured for each individual pocket (space between the suspended ceiling and the structural ceiling), and if any pocket exceeds 100 ft^3, that exemption doesn’t apply to it and sprinklers would be required there.