Which component must be checked as closed and plugged during visual inspection of foam concentrate strainers?

Which component must be checked as closed and plugged during visual inspection of foam concentrate strainers?

• A. Blowdown valve
• B. Isolation valve
• C. Drain valve
• D. Vent valve

Answer: (A)

Purge paths tied to the strainer must be secured during a visual inspection so nothing can escape or disturb the strainer while you’re observing it. The blowdown valve is the purge/flush line used to purge debris from the foam concentrate strainer, so it must be kept closed and plugged. If it were left open, concentrate could leak out, the purge could bypass the strainer, and the inspection wouldn’t reflect normal operating conditions. Isolation, drain, and vent valves have roles in isolation or venting, but the specific requirement to be closed and plugged for this inspection point to the purge line—the blowdown valve.

Purge paths tied to the strainer must be secured during a visual inspection so nothing can escape or disturb the strainer while you’re observing it. The blowdown valve is the purge/flush line used to purge debris from the foam concentrate strainer, so it must be kept closed and plugged. If it were left open, concentrate could leak out, the purge could bypass the strainer, and the inspection wouldn’t reflect normal operating conditions. Isolation, drain, and vent valves have roles in isolation or venting, but the specific requirement to be closed and plugged for this inspection point to the purge line—the blowdown valve.