Acceptance criteria should be set u

Acceptance criteria should be set up for the special scenario properly because if it is not set properly, the PQ may fail. For example, if after a power failure the water retains its quality characteristics for three hours, then a power failure of up to three hours can be followed by normal operation without any sanitization, provided the system integrity is not otherwise compromised and will only require documentation of the actual duration of the power failure. A special scenario test may be performed for a longer period than the period used as the limit, if there is a need for incorporation of a safety factor. The three-hour power failure scenario mentioned above is only an example and that shorter or longer times may actually be validated