MEASURAND : Thermal neutron fluence

Graph of equivalence

MEASURAND : Thermal neutron fluence

Degrees of equivalence Di and expanded uncertainty Ui (k = 2)

Results are presented under A4 printable format in Summary Results (PDF file).

Comparison close
CC comparison
Linked comparison
Metrology area, Sub-field Ionizing Radiation, Section III (Neutron Measurements)
Description Neutron fluence in thermal neutron fields
Time of measurements 2021 - 2024
Status Planned
Measurand Neutron fluence
Transfer device He-3 counter, naked and surrounded with a small diameter Bonner Sphere
Comparison type Key Comparison
Consultative Committee CCRI (Consultative Committee for Ionizing Radiation)
Conducted by CCRI (Consultative Committee for Ionizing Radiation)
Pilot institute LNE-IRSN
Institut de Radioprotection et de Sûreté Nucléaire
Contact person Vincent GRESSIER

+33 4 42 19 95 52
First Name Last Name
wwww@ww.www +356719836 Institute 1 Institute 1 Khmelnitskiy
Pilot laboratory

Institut de Radioprotection et de Sûreté Nucléaire, France, EURAMET


Bhabha Atomic Research Centre, India, APMP


Czech Metrology Institute, Czechia, EURAMET


Korea Research Institute of Standards and Science, Korea, Republic of, APMP


Laboratorio Nacional de Metrologia das Radiacoes Ionizantes, IRD, Brazil, SIM


National Institute of Metrology, China, APMP


National Institute of Standards and Technology, United States, SIM


National Metrology Institute of Japan, Japan, APMP


National Physical Laboratory, United Kingdom, EURAMET


Physikalisch-Technische Bundesanstalt, Germany, EURAMET


Nuclear Calibration Laboratory, Belgian Nuclear Research Centre, Belgium, EURAMET


D.I. Mendeleyev Institute for Metrology, Rosstandart, Russian Federation, COOMET

MEASURAND : Thermal neutron fluence

The key comparison reference value, xR, is taken as 1.

The degree of equivalence of each laboratory i with respect to the key comparison reference value is given by a pair of terms: Di = (xi - xR) and Ui, its expanded uncertainty (k = 2), both expressed in cm2/cm2. Ui = 2ui.
When required, the degree of equivalence between two laboratories i and j is given by a pair of terms: Dij = Di - Dj and Uij, its expanded uncertainty (k = 2), both expressed in cm2/cm2.
Pair-wise degrees of equivalence are given in Table 3 of the Final Report.

MEASURAND : Thermal neutron fluence

xi : measurement result obtained by laboratory i expressed as the mean ratio of measured instrument response by laboratory i to the reference instrument response
ui : combined standard uncertainty of xi

Measurements were performed between October 2006 and July 2010

 Lab i



 NMIJ 0.993 0.019
 NPL 0.918 0.025
 PTB 0.987 0.036