Duck and Cover Handbook PA 6 1951
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description
U.S. Federal Civil Defense Administration handbook PA-6, 1951, "Bert the Turtle Says Duck and Cover", for kids. Based on fact that blast arrival time over most the the area where windows are broken is many seconds, so if people duck and cover on seeing the recognisable flash (brighter than the noon sun), they can avoid being hit by blasted window glass fragments.The scientific basis of duck and cover is that people don't remain standing directly behind windows on seeing a silent flash. The sound and blast arrive simultaneously, taking about 4 seconds to cover each mile of distance (like thunder delayed after lightning flashes). See Glasstone's "Effects of Nuclear Weapons" 1962/64 edition, chapter 12, "Principles of Protection" (this chapter was deleted from the 1977 edition for political reasons, since FEMA separated from DOD, which published earlier editions).
Transcript of Duck and Cover Handbook PA 6 1951
