The space of secondary containment for an oil tank will be tested with a volume of what?

When performing a vacuum test for secondary containment of an oil tank, the standard volume used to measure the integrity of the containment system is typically 5.3 inches of mercury (Hg). This specific measurement is established to ensure that the containment system can hold any potential leaks or spills from the primary tank effectively.

The rationale for using this value is that it provides a reliable threshold for detecting leaks while remaining within safe operational limits. A vacuum level of 5.3 inches of Hg corresponds to a specific pressure that can help identify even minor defects in the containment structure. This level is widely recognized in industry practices and regulatory guidelines for testing secondary containment systems, ensuring compliance and safeguarding the environment against potential oil spills.

Other values mentioned in the options would either be too low or too high for standard testing measurements. Thus, using 5.3 inches of Hg is not only standard practice but also ensures thorough testing of the secondary containment system’s integrity.