his Code applies to ASUs of any size, in either a single-train or multitrain configuration. It can be used to measure the performance of an ASU in its normal operating condition, with all equipment in a new, clean, and fully functional condition. This Code provides methods and procedures explicitly for ASUs employing electric-motor-drive compression equipment, with or without the use of steam and/or electric power for internal regenerative processes. There is no intent to restrict the use of this Code for non-motor-driven compression equipment, nor for ASUs that use other heat inputs for internal regenerative processes, provided the explicit test procedures can be met.