Humidity

The NIST Temperature and Humidity Group maintains and develops national standards of humidity (in the range 1 nmol/mol to 0.6 mol/mol of water concentration), and supports calibration of all types of hygrometers and humidity generators.

Our goals include:

• Supporting the equivalence of humidity measurements in the U.S. and abroad, through calibrations, standardized methods, and comparisons and proficiency testing
• Providing customers access to the highest quality of humidity reference standards, through calibrations and reference data
• Developing improved humidity standards
• Supporting accurate measurements of humidity for various applications, such as fuel cells.

Hybrid humidity generator – NIST's new primary standard humidity generator, the Hybrid Humidity Generator (HHG), replaces the NIST 2-Pressure Humidity Generator, Mark 2 (2-P). The HHG produces humidified air...

Thermophysical properties of moist gases – To support humidity measurements needed for the efficient operation of fuel cells, we have calculated numerous thermophysical properties of water-gas mixtures at elevated pressures...