The analytical method used for gross activity was aeration followed by liquid scintillation counting, with evaporation followed by gas-flow detector counting as an alternative method. The method used for U-234; U-235; U-238; Pa-231; Th-232; Th-230; Th-228; Th-227; Ac-227; Ra-228; Ra-226; Ra-224; Ra-223; Po-210; and Pb-210 was radiochemical separation followed by alpha particle spectrometry; Internal yield tracer and certified efficiency calibration standards. As an additional method U-235, U-238 and Th-232 were also determined by sample atomisation followed by mass determination using chemical calibration standards.