One disadvantage of using a mechanical shaft seal instead of mechanical packing is that __________.

Correct Answer: Option A — seal failure usually requires the immediate removal of the pump from service

Mechanical seals are precision-engineered components. Unlike conventional packing, which can be adjusted or tightened while the pump is running to control leakage, a mechanical seal failure usually results in immediate, excessive leakage, necessitating the pump's removal from service for a complete seal replacement.