In closed systems, what is the leakage tolerance?

• A. Acceptable
• B. Not acceptable
• C. Unacceptable
• D. Seepage acceptable

Answer: (C)

In closed systems, zero leakage is expected. The whole purpose of keeping the system closed is to contain what’s inside and maintain the designed pressure without any loss to the environment. Even a tiny leak signals a breach in seals, joints, or components, which can lead to contamination, safety hazards, or degraded performance. Therefore, leakage must be undetectable under the test conditions; any detected leakage means the system fails the requirement and must be repaired and retested. Choices that imply some leakage is permissible—such as being acceptable, not acceptable, or seepage acceptable—don’t fit the goal of a sealed system.