Under which condition is a capstan hoist not deemed acceptable?

A capstan hoist is a specific type of lifting equipment that is often used in various applications, particularly in rigging and telecommunications work. Its designation as suitable for personnel lifting is crucial because it directly relates to safety and compliance with industry standards. When a capstan hoist is not rated for personnel lifting, it inherently lacks the necessary design, testing, and certification required to safely lift individuals. This lack of proper rating means that using the hoist in such a capacity poses significant risks, including failure of the hoist or accidents that could lead to serious injuries or fatalities.

In contrast, a capstan hoist rated for personnel lifting has undergone rigorous evaluation to ensure it can safely support the added weight and dynamic movements associated with lifting people. Therefore, using a hoist that does not meet this critical requirement is not acceptable under industry safety protocols.

For the other choices, they either describe situations that do not compromise the hoist's intended safe use (like standard lifting or modifications that may still adhere to safety standards) or concern scenarios involving proper ratings for personnel lifting. Therefore, the focus remains on the necessity of specific ratings to ensure safety when a capstan hoist is used.