ANSI/ISA-77.42.01-2019

provides comprehensive requirements for the design, measurement, control and safety of feedwater systems in fossil fuel power plants with steaming capacities of 200,000 lb./hr. (25 kg/s) or greater. It covers essential aspects such as drum-level, steam-flow and feedwater-flow measurements, control strategies for both drum-type and once-through boilers, protective logic, alarm systems and operator interfaces. This standard supports improved operational reliability, system integration and equipment protection by defining minimum criteria for effective feedwater control, making it a critical resource for engineers, designers and operators involved in fossil fuel power plant operations.