Temperature measurements

We provide traceable and flexible UKAS-accredited calibration services for a wide range of contact temperature measurement instruments. Validation of resistance bridge linearity is also offered. Our research has enabled the development of high temperature calibration techniques with unprecedented uncertainties.

• Clinical thermometer systems ISO80601-2-56
• Gold-platinum thermocouples: 0°C to 1000°C
• Platinum-palladium thermocouples: 0°C to 1500°C
• Platinum-rhodium thermocouples: 0°C to 1800°C
• Resistance bridges
• Standard platinum resistance thermometers: -196°C to 962°C
• Temperature fixed-point cells: -189°C to +1492°C

We provide traceable and flexible UKAS-accredited calibration services for non-contact temperature measurement instruments. Our expertise has enabled novel techniques to be developed, such as with a reproducible combustion flame.

• Optical combustion thermometers: 2040K to 2260K
• Phosphor thermometry
• Radiation thermometers (using high temperature fixed points)
• Radiation thermometers and blackbody sources
• Thermal imaging systems

We provide primary humidity standards and humidity calibrations with UKAS (ISO 17025) accreditation, for numerous hygrometer types, over a very wide range of humidity and temperature conditions. Calibrations are available in terms of relative humidity, dew point, frost point or other humidity quantities expressed as fraction, ratio or volumetric units.

As well as calibrations in air near atmospheric pressure, NPL provides humidity calibrations at higher pressures and in a variety of other gases and gas mixtures. We have expertise in carrying out measurements of moisture in materials, and related calibrations and instrumentation. Measurements can be water-specific, or can measure all moisture (which includes other volatiles and liquids) using a combination of instruments and our in-house developed techniques.

A variety of other humidity and moisture related services are available, including detailed characterisation of instruments, and calibration of humidity-generating devices such as humidity generators and humidity calibration systems based on salts or other reference materials. We also offer humidity training, design and build of humidity generators, and other problem-solving advice and consultancy.

• Air temperature sensors: -40°C to +100°C
• Calibration of humidity generators
• Dew-point temperature in air
• Humidity in gases and mixtures: 0.1 MPa to 3 MPa
• Humidity salts
• Moisture content of solids and liquids
• Relative humidity: 0.5 %rh to 98 %rh
• Temperature and humidity consultancy

We deliver world-leading and bespoke instruments for temperature and humidity measurement. They have been developed from our extensive research into how to enable faster, more accurate and reliable measurements. All instruments are offered with peripheral equipment for their operation and training, should these be required.

• Absolute temperature radiation thermometer
• Furnaces for contact temperature calibrations
• High temperature blackbody sources: 1153°C to 2748°C
• Humidity generators
• Platinum-palladium thermocouples
• Platinum-rhodium thermocouples
• Radiation thermometers (high temperature calibration)
• Self-validating thermocouples
• Standard fixed-point blackbody sources: 156°C to 1085°C
• Temperature fixed-point cells
• Variable temperature blackbody sources: -40°C to 1600°C

NPL offers consultancy services which enable access to our world-leading facilities and specialist expertise and span all aspects of temperature, humidity and moisture measurements.

Our expert advice and support covers:

• Problem-solving: rapid identification of the root cause and subsequent identification of preventative actions to enable product or measurement improvements
• Determining process measurement uncertainty: methodical, end-to-end assessment of a process or procedure to determine the measurement uncertainty budget
• Optimising performance: expert advice for achieving the best from measurement equipment and systems
• Bespoke instruments: professional design, manufacture, calibration and installation of world-leading and bespoke measurement instruments
• Tailored training: designed to meet business needs and adapt to the experience level of the staff
• Achieving high standards: assistance in working towards and achieving local and international best practices and Standards

Our facilities enable measurements traceable to internationally-agreed standards. We offer the most accurate and authoritative measurements in the UK, including quantified uncertainty. We maintain the UK National Standards that are validated through international comparisons.

Our measurement experts are authoritative, published and leading international experts in their fields. They have wide-ranging experience in the practical application of measurement technology. The team covers complementary disciplines and are available to help clarify requirements, interpret and analyse results. We have an internationally-recognised track record of high-value problem-solving. Operating as a National Measurement Institute, we offer trusted and impartial advice, plus a commitment to providing the right measurement solution.

Temperature enquiries

Humidity enquiries