The estimation of dose equivalent from the activation of plastic scintillators

It is shown that the dose equivalent to be attributed to the fluence measured by the activation of 11C in a plastic scintillator when exposed outside the shielding of a high-energy proton accelerator is close to the value of 28 fSv m2 in current use at the European Organization for Nuclear Research (CERN) when the neutron component of the field alone is considered. However the presence of significant numbers of pions and protons in stray fields would raise this conversion factor to approx. 45 fSv m2.