This is not specifically addressed in Q7A. However, for a new water system, both regulators and
industry generally recognize that there are various phases to validating the water system. Phases
1 and 3 generally last one or two months, and then you enter a third phase that may last up to a
year. During this third phase, you’re trying to show that the water quality is consistent throughout
the seasons and any other variations. Provided there is an appropriate ongoing testing program
as part of the validation, it is typical to use water during the final phases of validation of the water
system.
