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Physical Measurement Laboratory / Sensor Science Division

Temperature & Humidity Group

Projects/Programs

Displaying 1 - 7 of 7
Acoustic Thermometer

Acoustic Thermometry

Completed
Data from the NIST acoustic thermometer will form an improved basis for the equations used with platinum resistance thermometry, which is the primary mechanism to disseminate accurate temperature standards. Objective: To obtain measurements of thermodynamic temperature in the range between 273 K and
prototype system

Fixed Point Development : Non-Metals

Ongoing
A fixed point is a reproducible reference temperature, usually either melting of freezing of a pure substance, that allows a standardized interpolation scheme for the purposes of temperature scale dissemination. Most SPRTs are long-stem designs that require immersion-type fixed points incorporating
GH_gascollectionsys

Humidity

Ongoing
Our goals include: Providing SI traceability of humidity standards through use of standardized realization methods, and supporting humidity measurements in the U.S. and abroad through calibrations and proficiency testing Ensuring the equivalence of US humidity standards with those of other countries

Humidity Calibration Services at NIST

Ongoing
Humidity calibration services at NIST are performed with its primary standard humidity generator, the Hybrid Humidity Generator (HHG). The HHG produces humidified air of known moisture content over the dew/frost-point range from -90 °C frost point to +85 °C dew point, which corresponds to a water
NIST Shielded Room

Johnson Noise Thermometry

Completed
The NIST Gaithersburg JNT project produces data useful for verification of the International Temperature Scale of 1990 (ITS-90) over a temperature range from 500 K to 930 K. This range overlaps those covered by other thermodynamic methods, most notably the upper-most range of Acoustic Thermometry
triple point cell

Thermometry

Ongoing
The NIST Thermodynamic Metrology Group supports industry and advances measurement science through an extensive suite of thermometry calibration services as well as research projects aimed at improving the utility for the International Temperature Scale. We also develop guidelines, and contribute to