SUPPLIER shall so arrange the programme of construction that, on completion of construction of each individual unit or sub-unit of the PLANT, the individual unit or sub-unit may be subjected to appropriate mechanical completion tests, where necessary, services from other units or sub-units of the PLANT , On completion of construction of each individual unit and where appropriate SUPPLIER shall inform OWNER that the unit or sub-unit is complete (except for minor items which do not affect operability or safety of the PLANT) and ready for COMMISSIONING. SUPPLIER shall then agree with OWNER a programme for the mechanical completion tests and carry them out. OWNER shall witness such test has been successfully performed or note specific exceptions in writing. Should a test fail for any reason SUPPLIER shall make good and repeat, as for original test.