Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Tara Fortin (Fed)

Research Chemist


Dr. Fortin received her B.A. in Chemistry and Spanish from Wellesley College and her Ph.D. in Chemistry from the University of Colorado. Both her undergraduate and graduate research interests focused on atmospheric chemistry. As an undergraduate, she studied the reaction kinetics of a second-generation replacement for ozone-depleting CFC refrigerants; while in graduate school, her work focused on understanding the role of sulfate aerosol in both cloud formation and tropospheric chemistry. Post graduation, Dr. Fortin’s interests expanded to include energy science and policy, focusing primarily on industrial emissions of Hg, NO, NO2, NOy, and O3 and their impact on air pollution. Her interest in energy science has persisted since joining NIST in 2008 where she makes thermophysical property measurements (density, speed of sound, viscosity, and heat capacity) for industrially-relevant fluids, including both conventional and renewable fuels. She is also active in standards development via the ASTM Committee on Thermal Analysis and NIST Standard Reference Materials.

Google Scholar Citation Page

Research Areas

Thermophysical Property Measurements of Fluids

In recent years, there has been increasing pressure to enhance and extend traditional petroleum sources of fuels. This has led to the consideration of alternative sources such as natural gas and renewable feedstocks produced from biological sources. The production and utilization of these new fuels require an infrastructure of thermophysical property knowledge for use in equipment design and operation. Fundamental to this knowledge base are fluid density, viscosity, speed of sound and heat capacity. Dr. Fortin supervises a laboratory that provides these properties on real fuels, as well as other industrially-relevant working fluids such as lubricants and siloxanes. While the instruments in her laboratory all operate at atmospheric pressure, they have a wide temperature range of operation. This is ideal for measuring the properties needed to produce predictive thermophysical property models that are critical to the successful introduction of new fuels into the U.S. economy.

Instrument Development

The Thermophysical Properties of Fluids group has a longstanding tradition of utilizing one-of-a-kind instruments, developed in house, to make highly accurate thermophysical property measurements. Dr. Fortin is currently collaborating with Dr. Mark McLinden to put into operation a high-temperature single-sinker densimeter. The resurrection of this instrument will expand the group’s existing density measurement capabilities to temperatures up to 500 ˚C and pressures to 50 MPa.


  • CIRES Visiting Fellow, Center for Science and Technology Policy Research
  • NSF Atmospheric Chemistry Training Grant
  • NASA Earth System Science Fellowship for Graduate Study
  • CIRES Graduate Research Fellowship
  • Sigma Xi Scientific Honor Society


Low-GWP Alternative Refrigerant Blends for HFC-134a: Interim Report

Piotr A. Domanski, Mark O. McLinden, Valeri I. Babushok, Ian Bell, Tara Fortin, Michael Hegetschweiler, Mark A. Kedzierski, Dennis Kim, Lingnan Lin, Gregory T. Linteris, Stephanie L. Outcalt, Richard A. Perkins, Aaron Rowane, Harrison Skye
This project addresses the objectives of the Statement of Need number WPSON-17-20 "No/Low Global Warming Potential Alternatives to Ozone Depleting Refrigerants

Thermophysical Properties of Polyol Ester Lubricants

Thomas J. Bruno, Tara Fortin, Marcia L. Huber, Arno D. Laesecke, Eric Lemmon, Elisabeth Mansfield, Mark O. McLinden, Stephanie L. Outcalt, Richard A. Perkins, Kimberly N. Urness, Jason A. Widegren
This report summarizes the results of work performed for the Naval Air Warfare Center Aircraft Division by the National Institute of Standards and Technology
Created September 10, 2019, Updated June 15, 2021