In the last few weeks, several collateral warranties have crossed my desk which have required a consultant not to specify "materials which are becoming prohibited with the passage of time".
This goes beyond the usual requirement not to use materials generally known within the Consultant's profession to be deleterious/prohibited at the time of specification, but exactly how far into the future the consultant is supposed to gaze is not entirely clear! Query whether this would be enforceable, but it is definitely one to watch out for, and to delete if possible...
If you cannot remove this wording, the obligation should, at the very least, be subject to reasonable skill and care, so that you are not under an absolute obligation to comply.
