This guideline covers DDC for HVAC control@ monitoring@ and management functions. This guideline specifies hardware performance@ installation@ and training. It also addresses system architecture@ input/output structure@ communication@ program configuration@ system testing@ and documentation. The guideline does not include fire@ life safety@ or facility management functions. PURPOSE The purpose of this guideline is to provide recommendations for developing specifications for direct digital control (DDC) systems in heating@ ventilating@ and air-conditioning (HVAC) control applications.