Show j j FIVE DOORS to nowhere are set act in a test lest structure tote ture at the Nevada atomic tnt test site tUo to measure the blast Mast resistance of 01 various kinds of 01 common building materials Only the h hollow llo plywood door second from right was WAI blasted blatted from Us It frame at high pressure Other d doors or left t to right were er ermade made mAile of solid plywood od wood planking and two kinds of 01 steel atel shapes es Circular objects on the allare wait trail are blast anti valves tot for automatically closing closing- ventilation openings opening In case ease of a nuclear Mail blast INTO Lookout Mountain Lab Photo |