The scope of this standard is to address the major steam temperature control subsystems in boilers with steaming capacities for 200,000 lb/hr (25 kg/s) or greater. These subsystems include, but are not limited to, superheat temperature control, reheat temperature control. Specifically excluded from consideration are turbine bypass control, motor control logic, combustion control, sootblower control, as well as all controls associated with fluidized bed and stoker fired furnace combustion units.


The purpose of this standard is to establish the minimum requirements for the functional design specifications of steam temperature control systems for drum-type fossil-fueled power plant boilers.

Standards and Technical Reports

ANSI/ISA-77.42.01-1999 (R2011), Fossil Fuel Power Plant Feedwater Control System - Drum Type

ISA-TR77.42.02-2014, Fossil Fuel Power Plant Compensated Differential Pressure Based Drum Level Measurement

A Word from the Chairman

ANSI/ISA-77.42.01-1999 (R2011) is currently in its revision cycle.  For more information, please contact

Eliana Brazda
ISA Standards Administrator
(919) 990-9228

Jerry Gilman
ISA77.42 Chair