That a good question and it could be slightly trivial to answer. I believe that the original validation would not expire, but lets says there is a gap between the validation such as let’s say that you just did an installation qualification and process qualification on a new equipment, 30 yrs later you look at the validation of the equipment and notice that an OQ was never addressed, but aspects of the OQ were covered within the IQ. From my experience you would look at the validation as if it meets the standards ” of the day” since 30 years ago operation qualifications may have not exist but the IQ of the day slightly addressed one. You may need a memo from quality engineering that may have to be signed off to state that the validation package met the specification of ” the day”. Unless of course in the course of the 30 yrs the equipment was modified then maybe re-validation may be needed or a verification.

Chris