National Physical Laboratory


The NPL Neutron Metrology Group (NMG) operates world-leading facilities for measuring neutron source emission rates and providing extensive accelerator and source based calibration fields.
  • Collaborative work in the Neutron metrology area is undertaken with a number of organisations.
  • The manganese bath is the primary standard for neutron emission rate at NPL.
  • The primary objective of this work is to ensure the continued availability of national standards of neutron fluence and dose equivalent quantities.
  • NPL has a suite of neutron spectrometers that are used for characterising workplace fields in the nuclear industry or anywhere neutrons are a hazard. The devices are also used to derive knowledge about the spectra of standard neutron fields used for calibration and type testing.
  • NPL can undertake on-site spectrometry measurements which, in addition to providing information for radiation protection applications, can also be used, for example, to determine the neutron output from a range of devices.


Please note that the information will not be divulged to third parties, or used without your permission