 Plans were made, however, to use existing buildings with sturdy below-ground-level basements as makeshift fallout shelters.These buildings were placarded with the orange-yellow and black trefoil sign designed by United States Army Corps of Engineers director of administrative logistics support function Robert W. Blakeley in 1961.The National Emergency Alarm Repeater (NEAR) program was developed in the United States in 1956 during the Cold War to supplement the existing siren warning systems and radio broadcasts in the event of a nuclear attack.