IAPWS is currently based around four working groups and one subcommittee:
The purpose and interactions of the working groups is summarized in the figure. This structure was developed to promote collaboration and engagement between the working groups with the key aims of providing guidance to researchers on problems within industry and to provide engineers with the latest research results for direct application in their companies and facilities.
A subcommittee on seawater was established in 2008/9 to address a global need to support the understanding and standardization of thermodynamic properties for physical oceanography. IAPWS members subsequently developed the first fully consistent thermodynamic equation of state for seawater.
The Thermophysical Properties of Water and Steam (TPWS) focuses on the characterization of the thermophysical properties of water and aqueous systems.
The Physical Chemistry of Aqueous Systems (PCAS) focuses on the exploration and characterization of the fundamental physical and chemical properties of water and its various solutions.
The IAPWS Power Cycle Chemistry Group (PCC) is interested in water/steam related chemistry for steam power cycles in conventional fossil, combined cycle, nuclear, solar thermal, and geothermal power cycles.
The Industrial Requirements and Solutions (IRS) focuses on the calculation of thermodynamic properties of water and aqueous systems for industrial applications.
The subcommittee on seawater addresses a global need to support the understanding and standardization of thermodynamic properties for physical oceanography.