1 Scope This document reviews the recommended practices for the installation of electronic and pneumatic measurement and control-signal transmission systems. It does not discuss leased wire, radio, and telemetering transmission. The methods described are generally used throughout the United States. These methods are based on the assumption that the field devices, such as measuring transmitters, transducers, valve positioners, control valves, and other devices are properly installed. It is also assumed that the wiring, piping, and tubing at the control panel or Distributed Control System are properly installed. See the other appropriate API Recommended Practices and standards as needed.