Electrical submersible pumps (ESPs) can be an excellent choice for artificial lift needs in more difficult and harsh wellbore environments. Harsh or severe conditions include: Multiphase fluids or high GOR wells Fluids with abrasive particles Viscous fluids High-temperature wellbores Corrosive fluids Scale and asphaltenes In these environments, the demands on the equipment design functions, materials, and operational processes increase. The run-life of the entire system can be affected if proper designs for these applications are not used.

Authors: D. D. Smith , Oilfield Conformance Consulting LLC; A. Ambastha, Chevron; S. Ayirala , Saudi Aramco PE&D;   B. Bai , Missouri University of Science & Tech; P. Carreras , Blue Moon Strategies LLC; D. Hampton , OXY USA Inc.; K. Mohanty , The University of Texas at Austin; W. Rossen , Delft University of Technology; L. Schoeling, EOR Consulting LLC; A. Yousef , Saudi Aramco PE&D Summary Over the past several decades a variety of terms have been used to define the type, timing, and character of techniques that increase recovery. These terms have been used without a definitive recommendation from the Society of Petroleum Engineers (SPE). For this reason, 2024 SPE President Terry Palisch, with the guidance of Technical Directors Rodolfo Camacho (Reservoir) and Hamad Marri (Production), selected a committee of experts to evaluate these terms and provide guidance, clarity, and recommendations to SPE membership. This paper presents the charter document under which the committee has operated and the results of their discussions. The key elements of the charter are designed to provide recommendations on the following: 1. The relationship of improved oil recovery (IOR) to enhanced oil recovery (EOR). 2. The initial baseline for both IOR and EOR. 3. The relationship of terms primary, secondary, and tertiary to other recovery terms. 4. Refine the classification of recovery technologies that have characteristics that allow them to fall into multiple terms. 5. Provide guidance on how to classify current and future technologies that increase recovery.