What does NEC4 clause 60.1(11) mean?

Clause 60.1(11) deals with the Supervisor holding the work up. The event is that a test or inspection done by the Supervisor causes unnecessary delay. Three elements have to be shown. There was a test or inspection done by the Supervisor, as distinct from one the Contractor carries out and the Supervisor watches; the test or inspection caused delay to the Contractor's work; and the delay was unnecessary, meaning it went beyond the time the test or inspection reasonably needed, for instance because the Supervisor did not attend when notified, took longer than the Scope allows, or delayed telling the Contractor the result. Delay that a properly conducted test or inspection inherently causes is the Contractor's to allow for; only the unnecessary part is the event. That makes the record decisive: the notice given to the Supervisor, the time the Supervisor attended, the time the result was communicated and the time the work could have proceeded had the process been reasonable. The Contractor notifies the event under clause 61.3 within eight weeks of becoming aware of the delay. The change to the Prices is assessed under clause 63.1 as the effect on actual Defined Cost by the date of the notification and forecast Defined Cost afterwards, plus the Fee, which will mainly be standing people and Equipment for the unnecessary period and any resequencing cost. What most often goes wrong is that the Contractor did not give the Supervisor the notice of the test that the Scope required, so the Supervisor's late attendance was a response to short notice and not unnecessary delay, or that the Contractor claims the whole test duration rather than the excess. Any delay to the Completion Date is assessed separately under clause 63 by the programming expert.