Effects of Nuclear Weapons Testing GORDON M. DU:NING : Dv. Dunning is « health physicist with the Division of Biclagy and Moedicime, US. Atoma Energy Communes, Washington, D.C. His primary duties are oom corned wath biclogical effects of radiation, «specially as relatedte nucloer weapons tests, and he has participated in all of these tents mnce joining the commipnon in july (951. Me recawed his edacetion at Syrecess Unioeraty end nl masntems mterett in hes major field at the umvernity, that verit ceeded layers of the sumosphere may focus the blast i : producing greater presmeres than are usually peceed at tha powt (2). These refieceed onde Nevada Ten See. Total clams paid w j CURING che past decade the United Seats bees imjyured derecthy or mdirectly from blasts. Thus. there 5 some sight risk of manor or eee ee windows im arena i€ the was are contmued? (wii What do these data meam—how serous are the powsble risks? Stast aed Thermal Glast. The blast effects are lasted to areas meas the wee of detonation. Partial damage to structures may execad for about 2 mies for a sominal-ased bemb (equivalent im energy w 20,000 cons of TNT) (1) and for 10 miles of more for high-yield weapons. However, refleccion of blast waves from Oevembes 1955 poreniv bhad a prrmon if he jonks directly at it, even from a distance of 30 ww 40 miles The brilhance of a somal bomb mak that of 100 suns whee viewed at a distance of 6 miles | /). The simpie act of curning the head away from the lime of detomation can gre adequate protection. For these reasons, motorists near the Nevads Test Seer are warned prior to cach detonation. Ia the past, four military perwonne! participating in the Nevada tess have recened eve mjury—three superficial chee have compictely healed, and one senous. No cme has been miured off the tem ste. 263