Radiation and Radiological Disasters. This usage is specific to the Transport Regulations, and should otherwise be avoided. Radioactive material which by its nature has a limited specific activity, or radioactive material for which limits of estimated average specific activity apply. External shielding materials surrounding the LSA material shall not be considered in determining the estimated average specific activity. LSA Material Shall Be In One of Three Groups: (a) LSA-I (1) Uranium and thorium ores and concentrates of such ores, and other ores containing naturally occurring radionuclides which are intended to be processed for the use of these radionuclides; (2) Natural uranium, depleted uranium, natural thorium or their compounds or mixtures, provided that they are unirradiated and in solid or liquid form; (3) Radioactive material for which the A2 value is unlimited, excluding fissile material in quantities not excepted under para. 672; or (4) Other radioactive material in which the activity is distributed throughout and the estimated average specific activity does not exceed 30 times the values for activity concentration specified in paras 401-406, excluding fissile material in quantities not excepted under para. 672. (b) LSA-II (1) Water with tritium concentration up to 0.8 TBq/L; or (2) Other material in which the activity is distributed throughout and the estimated average specific activity does not exceed 10-4 A2/g for solids and gases, and 10-5 A2/g for liquids. (c) LSA-III Solids (e.g. consolidated wastes, activated materials), excluding powders, in which: (1) The radioactive material is distributed throughout a solid or a collection of solid objects, or is essentially uniformly distributed in a solid compact binding agent (such as concrete, bitumen, ceramic, etc.); (2) The radioactive material is relatively insoluble, or is intrinsically contained in a relatively insoluble matrix, so that, even under loss of packaging, the loss of radioactive material per package by leaching when placed in water for seven days would not exceed 0.1 A2; and (3) The estimated average specific activity of the solid, excluding any shielding material, does not exceed 2 x 10-3 A2/g