F.C.D.A. Family Shelter Evaluation; Operation Buster Project 9.1.a.

Washington DC: Federal Civil Defense Administration, 1952. reprint from the Defense Technical Information Center, circa 2004. Wraps, two staples on the left side. Good. xii, 87, [1] pages. Originally Secret Restricted Data document declassified to Unclassified. Mailing information on the back cover. The contents include Preface, Abstract, Introduction, Procedures, Results, Effects of Shot Baker, Effects of Shot Charlie, Effects of Shot Dog, Discussion, Conclusion, and Recommendations. Illustrations. Tables. Project 9.1.a Buster was designed to determine the effects of atomic explosions on small civil defense shelters for family use. Since limited participation in the program did not permit tests of all proposed shelter designs, four types of data shelters were selected. They were (1) covered-trench, (2) metal-arch, (3) wood-arch, and (4) basement lean-to. Twenty-nine simple structures were built along an arc 1200 ft from the target point. Construction was varied without regard to protective values and only to obtain technical data for design purposes. Effects of the first explosion added considerably to the damage normally resulting from the succeeding shots and cumulative damage was all that could be appraised. Test structures were severely damaged by the explosions. The wood-arch design proved unsuitable. The tests should that small shelters were potentially capable of providing a degree of protection commensurate with the requirements of civil defense. The information developed was expected to be used in modifying designs to provide safer shelters. Operation Buster-Jangle was a series of seven (six atmospheric, one cratering) nuclear weapons tests conducted by the United States in late 1951 at the Nevada Test Site. Buster-Jangle was the first joint test program between the DOD (Operation Buster) and Los Alamos National Laboratories (Operation Jangle). The last two tests, Operation Jangle, evaluated the cratering effects of low-yield nuclear devices. This series preceded Operation Tumbler-Snapper and followed Operation Greenhouse. The Federal Civil Defense Administration (FCDA) was organized by President Harry S. Truman on December 1, 1950 through Executive Order 10186, and became an official government agency via the Federal Civil Defense Act of 1950 on 12 January 1951. In 1958 the FCDA was superseded by the Office of Civil and Defense Mobilization when President Dwight D. Eisenhower merged the FCDA with the Office of Defense Mobilization. In its early years, the agency focused on evacuation as a strategy. The FCDA was first headed by Millard Caldwell under Truman, then Val Peterson under Eisenhower. A fallout shelter is an enclosed space specially designated to protect occupants from radioactive debris or fallout resulting from a nuclear explosion. Many such shelters were constructed as civil defense measures during the Cold War. During a nuclear explosion, matter vaporized in the resulting fireball is exposed to neutrons from the explosion, absorbs them, and becomes radioactive. When this material condenses in the rain, it forms dust and light sandy materials that resemble ground pumice. The fallout emits alpha and beta particles, as well as gamma rays. Much of this highly radioactive material falls to Earth, subjecting anything within the line of sight to radiation, becoming a significant hazard. A fallout shelter is designed to allow its occupants to minimize exposure to harmful fallout until radioactivity has decayed to a safer level. In the U.S. in September 1961, under the direction of Steuart L. Pittman, the federal government started the Community Fallout Shelter Program. A basic fallout shelter consists of shields that reduce gamma ray exposure by a factor of 1000. The required shielding can be accomplished with 10 times the thickness of any quantity of material capable of cutting gamma ray exposure in half. Shields that reduce gamma ray intensity by 50% (1/2) include 1 centimetre (0.4 in) of lead, 6 cm (2.4 in) of concrete, 9 cm (3.5 in) of packed earth or 150 metres (500 ft) of air. When multiple thicknesses are built, the shielding multiplies. Thus, a practical fallout shield is ten halving-thicknesses of packed earth, reducing gamma rays by approximately 1024 times (210).
Usually, an expedient purpose-built fallout shelter is a trench; with a strong roof buried by 1 m (3 ft) of earth. The two ends of the trench have ramps or entrances at right angles to the trench, so that gamma rays cannot enter (they can travel only in straight lines). To make the overburden waterproof (in case of rain), a plastic sheet may be buried a few inches below the surface and held down with rocks or bricks. Blast doors are designed to absorb the shock wave of a nuclear blast, bending and then returning to their original shape.