A refrigeration machinery room must have a one-hour fire-rated separation from the remainder of the occupancy unless sprinklered.

• A. 2-hour
• B. 1-hour
• C. 3-hour
• D. 4-hour

Answer: (B)

The idea is to limit fire spread from a refrigeration machinery room to the rest of the building. If the space is not protected by an automatic sprinkler system, it must be separated from the remaining occupancy by a fire-rated barrier rated for one hour. The sprinklered condition changes the requirement because the sprinkler system provides the necessary protection to control a fire in that room, so the 1-hour barrier is not required. Higher ratings (2-, 3-, or 4-hour) are not mandated by this rule, which is why the one-hour rating is the correct standard for non-sprinklered cases.