Television host Bob Day interviews Dr. Paul C Tompkins, the Laboratory Scientific Director. Tompkins, holding a radiation meter, explains how it measures. CU on piece of lucite exposed to radiation, plastioc lightning pattern inside. Mitchell Thermal Source device that produces intense heat and light, simulating thermal radiation from an atomic bomb. Block of wood receives concentrated beam and ignites in flames and smoke. Scientist hand turns block around to reveal blackened circle on wood.