1.1 Pot Fallout Collections for Radiostrontium lell New York City The New York City collection pot (exposed surface 0,82 ft=) is maintained on the roof of the Health and Safety Laboratory pbuilding. 1. The following are the conditions of collection and analysis: Samples were collected weekly from February 1954 through December 1956. 2. Since January 1957, samples have been collected monthly. 3. Duplicate pots have been exposed since July 1956. 4. Samples have been collected at the end of a calendar period regardless of whether this coincided with the end of a period during which precipitation occurred. Recent results of New York City fallout, not appearing in HASL-42, "Environmental Contamination from Weapon Tests" are summarized in Table 1. The cumulative data are graphically illustrated in Figure l. Normally the error term represents the maximum standard error of counting but when more than two samples are analyzed for the same period, the standard error of the mean is shown and used to compute the cumulative error term.