Fig. 3.

The comparative DRRs for nonhuman primates exposed to reactor-derived mixed gamma/neutron radiation at steady-state dose rate relative to reference radiation quality of 250 kVp, Co-60 gamma-radiation and 2 Mev x-radiation. The dose response relationships (DRR) for the: 1) primary 250 kVp x-radiation combined data set (n = 338) for dose in rads, dose rate range of 3–23 r min⁻¹, 2) two primary studies of TBI of rhesus macaques (n = 174 total) with 2 Mev x-radiation, 10.7 rad min⁻¹ (84), and Co-60 gamma-radiation, 54.6 rad min⁻¹ (90) and a single primary studies of TBI with mixed gamma/neutron radiation delivered at steady state (20 rad min⁻¹, n = 80) (MacVittie et al. 2015b). The database provided estimated RBE values for the LD50/30 NHP exposed to steady-state mixed gamma/neutron radiation relative to reference radiation exposure to 250 kVp, Co-60 γ-radiation and 2 Mev x-radiation of 1.35, 1.67 and 1.74, respectively.