Nevada Range: Operation Upshot-Knothole, “Dirty Harry” atmospheric nuclear detonation: most efficient low-yield fission explosion; tower explosion, 32 Ktons; causes one of the largest radiological disasters in North America: alone produces 30,000 of the total 85,000 roentgens/person of all North American nuclear tests; the overall increase in average radiation levels caused by all atmospheric nuclear tests is comparable to the difference in radioactivity perceived by someone living in a brick house (more radioactive) compared to someone living in a wooden house, and much less than the difference in radioactivity perceived by someone living at sea level or at 2000 m altitude.
