National Physical Laboratory

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      Collaborative research provides new insight into a fusion protein that enables HIV to infect host cells.
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    • The world's slowest clock

      Collaborative research between NPL and SUERC has calibrated the argon-argon clock, which is used to date geological events.
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    • Finite element code released

      'Zinc' is a multiphysics finite element code capable of solving a wide range of physics and multiphysics problems.
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      Thanks to NPL Training, the measurement associates are now thinking out of the box. We are already seeing a faster turnaround of measurement activities with higher accuracy and increased confidence. NPL is known for its technical expertise in this area, and can provide the highest level validated training. It's added to our professionalism and improved communication with our suppliers

      Mark Imms
      Metrology Manager
      Bentley Motors

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      BP Exploration has continued to benefit from NPL's world class corrosion testing and modelling capabilities in 2009, and we intend to cooperate even more closely in 2010 and beyond.

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      Programmes Manager
      Inherently Reliable Facilities Flagship BP
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    Measurement Network

    For anyone with an interest in measurement. It aims to facilitate the sharing of measurement knowledge and information between NPL scientists and members of the network, as well as providing a forum for the sharing and exchange of information and advice between members and other measurement experts.

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Hygrometers of all types in terms of relative humidity, dew point, mixing ratio or other humidity quantities

Hygrometers 

NPL can calibrate humidity instrumentation of practically all types, including:

  • relative humidity sensors
  • dew-point hygrometers
  • psychrometers
  • spectrometers
  • humidity generators
  • climatic chambers and others

Reference gas can be supplied by connection to a humidity generator, or by immersion in a temperature and humidity controlled chamber.

Calibrations of integral air temperature sensors are also offered. 

Calibrations can be reported in other humidity quantities and units directly related to dew point, e.g. vapour pressure, amount fraction, vapour density (g/kg), etc. Advice can be given on conversion between units.

Contact

Customer Service tel: +44 20 8943 8681
E-mail: humidity_enquiries@npl.co.uk

Last Updated: 13 Jul 2010
Created: 13 Jul 2010