Kindly I would like more Explanation about this clause:
"However,Whenever the Engineer exercises a specified authority …The Employer shall be deemed to have given approval.
(d) any act by the Engineer …within 28 days of receipt.
In general this clause is giving the Contractor comfort that when the Engineer exercises his authority under the contract he is doing so with the express or implied consent of the Employer. This prevent the Employer distancing itself from the acts of the Engineer.
Which form in particular are you looking at as that wording in not used in the new Second Edition and the approach is slightly different. (d) does not appear in the Red Book of the First Edition.