Airblast was measured perpendicular to and off the ends of row-charge explosions and compared with airblast from single charges. It was found that Prow was approx. n(B) Psingle, where P is peak overpressure and n the number of charges. B was different for each blast parameter examined: ground-shock-induced peak overpressure, peak overpressure from venting gas, peak negative pressure, and positive and negative impulse. Values of P increased as spacing decreased. Airblast was always greater perpendicular to the row than off the end, by an amount which increased as the number of charges increased.

Airblast was measured at distances of 2000 to 61,000 feet from a detonation of four million pounds of ammonium nitrate. The charge was horizontally dispersed in three vertical layers. The top layer contained 0.596 million pounds; the second, 160 feet below, contained 2.119 million pounds and was detonated 87 msec after the first; the third, 100 feet below the second, had 1.285 million pounds and was detonated 144 msec after the first. Attempts to reproduce measured ground-shock-induced peak overpressure using results of previous single, row, and array-charge explosions showed best agreement with the equivalent row-charge analogy, which produced 80 percent of measured values.

Considers H.R. 477 and identical H.R. 10288 and companion S. 1885, to amend the Atomic Energy Act to authorize AEC to provide peaceful nuclear explosives to commercial domestic and foreign concerns under an expanded Plowshare Program. Includes report "Nuclear Construction Engineering Technology" by Lt. Col. Bernard C. Hughes, Sept. 1968 (p. 447-629).