is usually tcc fseble to msasure with a hand monitor -— that air sampling does not give precise results as the ameunt of the passing air does not bear a direct relationship to what falls on the ground, The best measures of the astual fallout available to date are laboratory analysis cf fallcut on gummed paper, in collecting pots, and actual analysis of the scii, There is a dissussisn of atmcspheric radiocontamination as a result of unsontrolled release of materials such as radio~ krypton and radiciodine from power reactors and precessing plants, They point out that continued centrol over release of these pro- ducts as is now dena is essential, Control is by permitting a "eooling” time for short~lived radicactive materials to decay away, by off-gas cleaning, and by scheduling release cf materials with due regard to metecrcicgizal conditions at the tims, There is a sssticn on possible uses of radivcactive materials in the study of the setence of metecrolegy, Natural radon gas in the «ir tan ts helpfcl in understanding vertical move- ments of air from the land, Weapcens tests have taught much with respect to lateral spread of air masses at vericus altitudes = how rain scavenges ths atacephers of partic des = the rate of transport from the stratosphere to the trsposphere and the removal time for water from the atmo sphere, Experiments could be conducted using introduced radisactive materials under controlled conditions to study air flew ard diffusion rates, hydrometecrology, i.8%., con= densation, precipitation and evapcration, and to study electricity of the atmesphere espe ey the pissible relationship cf electri- cal fields to the weether As to effects of nuclear weapons testing on the weather the committee statad: for rain, 1, Nuclear Weapon debris was not effective as a seeder 2. The amount of ionizaticn produced is insignificant in meteorcicgical terms,’ NAS 3, There has been nc measuable decrease in the amount of direct sunlight reaching the earth whereas voleansces have known to decrease it by as much as 10-20% for appreciable periods of time. b qo NE Ce c a mi 4, The apparent recent increase in severe storms is probably the result of “improvad metheds of reporting."