How should piping with unknown contents in the Critical AOC be treated?

How should piping with unknown contents in the Critical AOC be treated?

• A. Treat as hazardous; notify operator, monitor with gas detectors, and suspend work until contents identified.
• B. Immediately excavate to locate pipe.
• C. Ignore contents and proceed with standard procedures.
• D. Flush contents with air before work.

Answer: (A)