1.1This test method covers procedures for measuring reaction rates by assaying a fission product (F.P.) from the fission reaction ²³⁷Np(n,f)F.P.

1.2The reaction is useful for measuring neutrons with energies from approximately 0.7 to 6 MeV and for irradiation times up to 30 to 40 years.

1.3Equivalent fission neutron fluence rates as defined in Practice E261 can be determined.

1.4Detailed procedures for other fast-neutron detectors are referenced in Practice E261.

1.5The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

1.6This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.