The Integral Systems Test (IST) Program was initiated in 1982 by government and industry to provide information needed to help resolve issues raised by the accident at the Three Mile Island nuclear power station. Three different integral test facilities, each scaled to a Babcock and Wilcox (B and W) design nuclear steam supply system, will ultimately contribute data to meet the objectives of the program. Each of the facilities was designed using different scaling methodologies, and each has different operating capabilities, such as maximum operating pressure and core power. The overall scaling of each facility is examined in this report, and local scaling is analyzed to demonstrate potential similarities and dissimilarities in facility response relative to expected plant responses. The scaling relationships are used to show how local thermal-hydraulic phenomena in each facility can be compared to each other or to expected plant behavior. The concept of an equilibrium plot is used to show how the global response of each facility can be related for a specific small break loss-of-coolant transient. Potential complications that may arise as a consequence of the facility scaling or facility limitations are enumerated. The potential use of dimensionless groupings for relating and specifying experiments ismore » discussed. Finally, some specific experiments and conditions are proposed for the purpose of simplifying interfacility comparison of test results.« less