Spectra simulated using GADRAS-DRF, with a 7.5 cm diameter equivalent detector face, and depth of 7 cm for the NaI crystal. An outside scattering environment was used, with the detector at a height of 100 cm. Background is estimated for Livermore Ca. Background: 1800s 241Am,50uC @50cm, 600s 109Cd,50uC @50cm, 600s 57Co,50uC @50cm, 600s 88Y,50uC @50cm, 600s 133Ba,50uC @50cm, 600s 137Cs,50uC @50cm, 600s Co60,50uC @50cm, 600s Na22,50uC @50cm, 600s U232,50uC @50cm, 600s Na22,25uC @50cm + F18,25uC @50cm, 600s