The discharge size of the Inspector's Test connection shall be equal in size to which of the following?

• A. The largest sprinkler in the system
• B. The median sprinkler in the system
• C. The smallest sprinkler in the system
• D. Not related to sprinkler sizes

Answer: (C)

Sizing the Inspector’s Test connection discharge to the smallest sprinkler in the system ensures the test flow is representative and conservative for all heads. The test is meant to simulate the water that the system must be able to deliver when a sprinkler operates, so tying the discharge to the smallest head prevents a test flow that would exceed what the most restrictive head could handle or that would distort pressure losses in the piping. This provides accurate assessment of the water supply, pump capacity, and system performance across the entire system, including the smallest head. If the test discharge were larger, it could create unrealistically high flow and pressure conditions, masking deficiencies or stressing components beyond their design, whereas matching it to the smallest head keeps the test within the system’s worst-case demand.