During an annual inspection, a small addition increases the enclosure volume. What action should be taken?

• A. Perform a door fan test
• B. Ignore the change
• C. Repaint the enclosure
• D. Replace the door

Answer: (A)

When an enclosure grows, the ability to contain hazardous materials depends on preserving the specified pressure boundary and keeping leakage within allowed limits. The door fan test directly checks the enclosure’s integrity under the new volume by pressurizing or depressurizing the space and measuring how much air leaks through closures. This verifies whether the existing ventilation and sealing are still sufficient to maintain the required differential and prevent migration of hazards. If the test shows excessive leakage or an unable-to-reach target pressure, adjustments to seals, doors, or ventilation must be made and retested.

Ignoring the change isn’t appropriate because the containment performance could be compromised. Repainting or replacing the door isn’t related to the volume change or the integrity test needed to confirm safe performance.