This committee covers the mechanical design, engineering, fabrication, installation, testing, and protection of fossil power plant instrumentation sensing and control lines. The boundaries of their standard span the process tap root valve to the instrument connection. Their standard applies to all fluid media (liquid, gas, or vapor).


This committee established the applicable installation requirements and limits of instrumentation sensing and control lines and their instruments in fossil power plants.

This committee addresses the requirements of maintaining the pressure boundary integrity of the instrumentation sensing line (in accordance with the appropriate parts of American National Standards Institute [ANSI] standards).

A Word from the Subcommittee Chair

The reaffirmation has been completed for ANSI/ISA-77.70.02-1994 (R2010), Fossil Fuel Power Plant Instrument Piping Installation.

The subcommittee also revised and published ANSI/ISA-TR77.70.01-2010, Tracking and Controlling Instrument Documentation in Fossil Power Plants.

If you are interested in contributing to the work of the subcommittee, please contact Chair Jody Damron, or ISA Standards Administrator Eliana Brazda at or (919) 990-9228.