Learn to love ECC clause 14.1....

...and the equivalent in other NEC3 contracts.

To remind us, the clause says "The Project Manager's or the Supervisor's acceptance of a communication from the Contractor or of his work does not change the Contractor's responsibility to Provide the Works or his liability for his design."

So the ECC  requires the Project Manager (PM) and Supervisor to accept various things at various times:
- the PM accepts the Contractor's design (clause 21.2)
- the PM accepts a submitted Contractor's programme (clause 31.3)
- tests may be accepted by the Supervisor as being required in the WI
and so on.

The contract uses 'acceptance' and not 'approval' (the latter being legally problematic of course) and basically is saying even if the PM accepts a Contractor's design, if the design later proves to be wrong the Contractor is still liable for his design. Nothing has changed through the acceptance.

I'm not suggesting for one minute therefore that PMs/Supervisors become cavalier but we've previously discussed people's reluctance to say yes but you have the whole weight of this clause behind you. Try to say yes, work with the Contractor to say yes, possibly even give them the slight benefit of the doubt and appreciate that, if there is a problem then the Contractor is still 100% responsible to Provide the Works and 100% responsible for any design the WI states he is to design. Then if there is a problem, roll your sleeves up and get stuck into helping him fix the problem.