Which of the listed operating practices is considered as safe, and should be followed when opening and inspecting the waterside of a boiler?

Correct Answer: Option C — Wire all valves closed that connect to other boilers.

Safety regulations mandate that any valve connecting a boiler to shared steam, feed, or blowdown systems must be securely locked and tagged or wired closed to prevent accidental steam admission or chemical blowback while personnel are working inside the boiler watersides.