Identifies a basis for evaluation of functional hardware performance of digital process computers. Process computers are characterized by capability to acquire real-time data from a process in digital or analog form. Also, a process computer is usually capable of providing digital and analog control signals to the process. Deals with general recommendations covering all hardware performance testing, specific tests for relevant subsystems and system parameters, and a short glossary specifying terms used in the Recommended Practice. Detailed specifications are needed to define system acceptance criteria, and these should be negotiated between vendor and user before the system is contracted.