This standard specifies principles for project specification, implementation and for integration of other systems into the BACS. This standard defines terms to be used for project implementation. The BACS implementation process normally commences after the client appoints a BACS consultant or supplier. The quality of the implementation of a BACS is dependent on the design of the building systems and the specification of the commissioning process. This document also provides guidance for review and improvement of building performance after completion. This part of the standard describes the phases required for the implementation: - design: definition of project requirements, - engineering: detailed function and hardware specification design; - installation: commissioning of the BACS; - completion: acceptance; Work done during the engineering, installation and completion phases will serve as a basis for providing training and as built documentation.