An operator observes a 'Danger - Confined Space - Entry Permit Required' sign on an industrial vat that needs cleaning. What is the minimum essential requirement before any entry can be considered, aside from atmospheric testing?

Question: An operator observes a 'Danger - Confined Space - Entry Permit Required' sign on an industrial vat that needs cleaning. What is the minimum essential requirement before any entry can be considered, aside from atmospheric testing?

Answer options:

• A designated stand-by person (attendant) trained in confined space rescue. ✅ Isolation of all energy sources (lockout/tagout).
• A written rescue plan posted at the entry portal.
• A ventilation fan operating before and during entry.

Correct answer: Isolation of all energy sources (lockout/tagout).

Explanation: Before entering any permit-required confined space, all energy sources feeding into the space must be isolated (lockout/tagout) to prevent accidental activation and ensure worker safety, as per OH&S regulations.