This fact sheet describes the purpose, lab specifications, applications scenarios, and information on how to partner with NREL's Energy Systems Sensor Laboratory at the Energy Systems Integration Facility. The mission of the Energy Systems Sensor Laboratory at NREL's Energy Systems Integration Facility (ESIF) is to research, develop, test, and evaluate the performance of commercial and developing hydrogen sensor technologies to support the needs of the emerging hydrogen infrastructure. Sensor performance metrics analogous to national and international standards are quantified. Information gained from the sensor testing is provided to the sensor manufacturers to aid in sensor development, to end users to guide sensor selection and deployment...