The scope of this standard is to address the major combustion control subsystems in boilers with steaming capabilities of 200@000 lb/hr (25 kg/s) or greater. These subsystems include@ but are not limited to@ furnace pressure control (balanced draft)@ airflow control@ and fuel flow control when firing coal@ oil@ gas@ or combinations thereof. Specifically excluded from consideration are development of boiler energy demand@ all burner control@ interface logic systems@ and associated safety systems@ as well as all controls associated with fluidized bed and stoker-fired combustion units. Purpose The purpose of this standard is to establish the minimum requirements for the functional design specification of combustion control systems for drum-type@ fossil-fueled@ power-plant boilers.