Measurement of delayed neutron emission from water activated by 14 MeV neutrons in a FW mock-up of ITER

•Water activated by 14 MeV neutrons emits both high energy gammas from 16N and delayed neutrons from 17N.•These sources of radiation represent one of the main issues for ITER, need to validate the calculation methodology for ITER.•An experiment was commissioned by F4E to ENEA.•6.73 MeV gamma-rays from 16N and neutrons from 17N were measured by CsI g-detector and an array of 3He counters, respectively.•Calculation performed using MCNP code coupled to the FENDL3.1 data library and the EASY-2007 inventory code.•The C/E ratio is close to unity, it is affected by an error > ±60% to be ascribed nuclear data used for calculation.