Art Burns must be repaired or removed if the pipe has hoop stress of what percentage or more?

In the context of repairing or removing a pipe due to hoop stress, identifying the correct percentage is critical for ensuring the integrity and safety of the piping system. Hoop stress refers to the stress exerted circumferentially in a pipe due to internal pressure. When the hoop stress reaches a certain threshold, it indicates that the pipe may be compromised and could potentially fail under working conditions.

The correct choice, which indicates that repairs or removal must occur at 40% hoop stress or more, stems from industry standards and safety protocols. Generally, a hoop stress of this magnitude suggests that the pipe is significantly under strain, which can lead to leaks or catastrophic failure if not addressed promptly. This threshold ensures that any potential weaknesses or defects in the pipe will be treated proactively, thus safeguarding the entire system's functionality and reliability.

The other percentages, although they might seem plausible, do not align with the recognized levels of hoop stress at which immediate action is required. Lower thresholds may not adequately account for the risks associated with higher percentages of hoop stress, which underscores the importance of using the 40% metric in practical applications.