Which statement correctly describes the required sequence of testing prior to the expansion and drainage test?

• A. Foam solution-concentration test, turret ground pattern test, and expansion and drainage test must be preceded by verification steps
• B. Expanded sequence is optional
• C. Only expansion and drainage test is required
• D. Testing is not required before expansion and drainage

Answer: (A)

Before performing the expansion and drainage test, a specific sequence of checks must be completed to ensure safety and accuracy. Start with verification steps to confirm the system is ready to operate, including basic readiness and safety interlocks. Then verify the foam solution-concentration to make sure the foam-to-water ratio the system delivers is correct, because an improper mix would skew expansion and drainage results. Next, run the turret ground pattern test to confirm the nozzle pattern, flow, and reach are as designed; a correct pattern is essential for meaningful expansion measurements. Only after these steps are confirmed should you proceed with the expansion and drainage test, which assesses how the foam expands and drains under properly configured conditions. Skipping verification or the preparatory tests can lead to inaccurate results or hidden equipment faults.