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Measurements and Calibrations


Dimensional Measurements
Services include Length Measurements, Diameter Measurements, Complex Dimensional Standards, Optical Reference Planes & Roundness Standards, Angular Measurements, Laser Measurements, and Surface Texture.
Electromagnetic Measurements
Services Include Resistance Measurements, Impedance Measurements, Voltage Measurements, Precision Ratio Measurements, Phase Meters & Standards & VOR Standards, Power & Energy Measurements, RF Microwave & Millimeter Wave Measurements, Electromagnetic Field Strength & Antenna Measurements and Pulse Waveform Measurements.
Frequency Measurement and Analysis Service
The NIST Frequency Measurement and Analysis Service makes it easy to measure and calibrate any quartz, rubidium, or cesium frequency standard. All measurements are made automatically, and are traceable to NIST at an uncertainty level of ±5 × 10-13 per day. Subscribers to the NIST service receive a complete frequency measurement system which includes everything needed to make state-of-the-art frequency measurements that are traceable to NIST.
Mechanical Measurements
Services include Hydrometers, Volume and Density, Flow Measurements, Air Speed Instruments, Mass Standards, Force Measurements, Vibration Measurements, and Acoustic Measurements.
NIST Global Positioning System (GPS) Data Archive
NIST continuously monitors the Global Positioning System (GPS) satellite signals from Boulder, Colorado and compares the frequency standard on each satellite to the NIST frequency standard. The results are published in the NIST GPS Data Archive. The archived data can be used to support claims of frequency traceability to NIST through the use of GPS, since the frequency uncertainty of each satellite is listed. You can use the archive to quickly check the status of the GPS constellation on any given date. New GPS data (from the previous day) are added to the archive daily at about 1600 UTC.
Special Tests
Services include algorithm testing, long length standards, metal tapes, precision metal rulers, ranging tests for laser scanners, ranging tests for laser trackers, and volumetric tests for coordinate metrology instruments.
Spectrometer Calibration Beamline
Beamline 2 (BL-2) at SURF III is dedicated to spectrometer calibrations, and provides a standard source of irradiance from 4 nm to 400 nm.
Thermodynamic Quantities
Services include Pressure Measurements; Vacuum Comparison Calibrations; Low Pressure, Vacuum, and Leak Measurements; Laboratory and Industrial-Grade Thermometers; Thermocouples, Thermocouple Materials, Thermometer Indicators; Resistance Thermometry; Radiance Temperature Measurements; Humidity Measurements and Thermal Resistance.

NIST Time Services

NIST Web Clock
See a display of what time it is anywhere in the country. The reference for the clock is the NIST Time Scale in Boulder, CO.
Automated Computer Time Service (ACTS)
NIST's Automated Computer Time Service (ACTS) has been provided since 1988 to those users who need to synchronize computer clocks to the correct time. Using ACTS requires only a computer, a modem, and some simple software. When a computer connects to ACTS by telephone, it receives an ASCII time code. The information in the time code is then used to set the computer's clock.
NIST Internet Time Service
The NIST Internet Time Service allows users to synchronize computer clocks via the Internet. The time information provided by the service is directly traceable to UTC(NIST). The service responds to time requests from any Internet client in several formats including the DAYTIME, TIME, and NTP protocols.
Time Measurement and Analysis Service (TMAS)
The NIST Time Measurement and Analysis Service (TMAS) was designed to serve any organization that is required to maintain an accurate local time standard. The basic TMAS service monitors the customer's local time standard by continuously comparing it to UTC(NIST), the national time standard for the United States, and reports new results via the Internet to the customer every 10 minutes. The optional NIST disciplined clock (NISTDC) add-on to the TMAS will lock the customer’s standard to UTC(NIST), essentially replicating the national time standard at the customer’s facility.

Optical Technology Calibration Services

General Laser Measurements
The Applied Physics Division conducts research on a variety of problems in the characterization of optoelectronics components. Examples of measurement areas include beam profile, optical density or attenuation, and detector linearity. We also support instrumentation used with optical fiber power systems offering various optical fiber power related measurements upon request and by prearrangement. These include optical attenuator characterization, high power measurements, and power meter measurements involving unusual connector or fiber types.
Laser Power and Energy
The Applied Physics Division currently provides calibration services for meters used with the lasers, wavelengths, and power ranges shown in the following table. Other laser wavelengths, power, and energy levels are available upon request as Special Tests.
Low Background Infrared Measurements
The LBIR Facility is available to service the user community to characterize infrared radiometric sources, detectors and optical components in a low background environment. The scientists at the facility will collaborate for special tests to measure infrared optical properties of materials, to characterize sources and detectors and to perform other experiments at cryogenic temperatures.
Spectral Responsivity Measurements
This service provides characterized silicon detectors and special tests of customer supplied detectors. Spectral responsivity and uniformity measurements are made on photodiodes, detectors, and radiometers from 200 nm to 1.8 µm.
Photometric Measurements
Various calibration services are now available for luminous intensity, total luminous flux, illuminance, luminance, and color temperature.
Radiance Temperature Measurements
Measurement of Radiance Temperature of Disappearing Optical Pyrometers, Ribbon Filament Lamps, and Radiation Thermometers provide access to the International Temperature Scale of 1990 (ITS-90). NIST disseminates the radiance temperature scale from 800 °C to 2700 °C by issuing ribbon filament lamp standards of radiance temperature and by calibrating customer supplied pyrometers and radiation thermometers.
Spectroradiometric Source Measurements
Spectral radiometric measurements of radiance and irradiance standards in the spectral region of 200 nm to 2400 nm are performed. Spectral irradiance standards are supplied by NIST in two forms: tungsten filament lamps and deuterium lamps. Special tests are available.
Measurements of regular transmittance and specular or diffuse spectral reflectance from 250 nm to 2500 nm on submitted text items.
Surface color and appearance measurements
Through Calibration Services, NIST offers measurements of 0°/45° colored samples; 20°, 60°, and 85° specular gloss calibrations; colorimetric characterization of gonioapparent coatings; and calibrated photographic and X ray step tablets.
Created August 11, 2009, Updated April 15, 2020