Section 28A(3) in The M.P. Licensing Board (Electrical) Regulations, 1960
(3)On submission of the test report, the contractor shall not be held responsible for any defect in the installation except such defects or violation of rules which are attributable to his negligence or improper workmanship and noticed before the expiry of a period of three months from the date of submission of test report under clause (2).]