When is it acceptable to skip insulation removal during an external inspection?

Skipping insulation removal during an external inspection is generally considered acceptable when there is no reason to suspect corrosion. This approach aligns with risk-based inspection practices, where inspectors evaluate the condition and history of the equipment. If there are no signs, indications, or prior evidence of corrosion, it may be reasonable to conduct an external inspection without disturbing the insulation, thus saving time and resources.

Insulation plays a critical role in protecting the vessel and maintaining operational efficiency. However, if the external conditions and past maintenance records suggest that the vessel is in good condition, removing insulation may not only be unnecessary but could also lead to the introduction of new materials or damage to the insulation itself.

While other answers present various scenarios, the decision to skip insulation removal hinges primarily on the absence of corrosion concerns—as highlighted in the correct answer. The condition of the vessel, historical data, and inspection findings are key factors, not merely the age or cleanliness of the insulation.