October 15, 1961 which is the average production date of this nucl in the 1961 test series. D This is not to convey that ali the Fe-55 currently in the stratosphere originated in the 1961 tests. vert pci/100 SCM to disintegrations per minute per 10° standard cuk feet multiply by 0.6295. One standard deviation of the counting error for all data in m t To co; this report is less than +20% and usually less than +10% unless annc tated with the symbols: As One standard deviation of the counting error is between Bs One standard deviation of the counting error is between +51 = 100%. *; Activity is not detectable. +20 - 50%, This designation is applied to data when one standard deviation of the counting error is greater than +100%. @o J , The nuclide concentration of a specific sample is considered suspect because it is inconsistent with the concentration of the same nuclide in adjacent samples in space and time or becaiise it is inconsistent with Other nuclides in the same sample. The nuclide activity for each sample is corrected for the normal radiochemical parameters such as chemical yield and detection efficiency, but it is important to note that a blank adjustment is also made. The value of the adjustment is determined for each nuclide by analyzing a number of blank samples, that is, samples containing no It - 12 . woe “a rr aeer " 6 ~ “ . ee all ‘ «