A phrase often within the industry to specify that a cause of loss must be both sudden and accidental. Policy language however seldom refers to this phrase when discussing covered causes of loss. See Sudden and Accidental, Is it Really a Thing?
Insurance Encyclopedia
Sudden and Unforeseen Damage
The wide form of words used in Engineering Insurance Policies to cover damage to the insured plant from both internal and external causes.
Sudden and unforeseen physical damage
The widest form of material damage cover under engineering insurance policies. It includes breakdown risks, including electrical and mechanical breakdown, and accidental damage. In short the damage can be from internal or external causes.
Sudden death clause
Reinsurance treaty clause requiring or permitting termination of the contract in the event of a change in control of the ceding office, the insolvency of either party and certain other defined events.
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A clause which automatically terminates the Reinsurance contract if either party becomes insolvent.
Sudden, unintended, unexpected pollution
See: POLLUTION CLAUSE.