Radioactive material, surface contaminated objects

RADIOACTIVE MATERIAL, SURFACE CONTAMINATED OBJECTS (SCO-I orSCO-II) non-fissile or fissile-excepted ... 

During any release of radioactive materials, surfaces of objects or equipment may become contaminated. The objective of these measurements is to identify those objects that should be decontaminated, disposed of as waste, or treated in some other controlled fashion. The physical quantity that is generally measured is surface activity. Measurements may be radionuclide-specific or can also be assessed based on dose-rate measurements. The results are generally expressed in Bq/m or Sv/h or equivalent, respectively. 

For transportation Surface-contaminated objects (SCOs) are of special interest SCO means a solid object which is not itself radioactive but which has radioactive material distributed on its surfaces. SCO is classified in one of two groups ... 

Less dangerous radioactive materials permit less stringent packages. Specifically, Industrial Package Types 7, 2, and 3 are in use for low-specific activity (LSA) materials and surface-contaminated objects (SCO) ... 

Radioactive materials are grouped according to their form and/or characteristics. These include Special Form Low Specific Activity (LSA) Surface Contaminated Object (SCO) Fissile Other Form. A radioactive material may meet the definition of one or more of the above. lATA 10.3.3... 

Surface contaminated objects are by definition objects which are themselves not radioactive but have radioactive materials distributed on their surfaces. The implication of this definition is that objects that are radioactive themselves (e.g. activated objects) and are also contaminated cannot be classified as SCOs. Such objects may, however, be regarded as LSA material insofar as the requirements specified in the LSA definition are complied with. See also para. 226.19. 

Conveyances may become contaminated during the carriage of radioactive material by the non-fixed contamination on the packages. If the conveyance has become contaminated above this level, it should be decontaminated to at least the appropriate limit. This provision does not apply to the internal surfaces of a conveyance provided that the conveyance remains dedicated to the transport of radioactive material or surface contaminated objects under exclusive use (see para. 514.1). 

Contamination (radioactive)— The deposit of unwanted radioactive material on the surfaces of structures, areas, objects, or people where it may be external or internal. 

However, many entities in the United States routinely free release objects with surface contamination above the IAEA s minimum level. The effect is that the US DOT regulations may require radioactive material markings in transportation on items that have been free released in accordance witii the terms of a governing radioactive materials license or DOE policy. The DOT clarified its position in the 2014 revision of 49 CFR 173.443, and in discussion in the Federal Register notice of changes to the HMR 79 FR 40589 0618. 

Contamination (radioactive) the deposit of unwanted radioactive material on the surfaces of structures, areas, objects, or people where it may be external or internal Contingency plan an emergency plan developed in expectation of a disaster contingency plans are often based on risk assessments, the availability of human and material resources, community preparedness, and local and international response capabilities... 

Measurements have been made by a Joint Norwegian-Russian Expert Group of the release of activity at the disposal sites for reactor compartments at Novaya Zemlya. Surface sediment samples at the sea bottom taken close to the dumped reactor compartments and the sunken submarine showed in a few cases activities of up to about 10 kBq/kg, but in most cases the activity of the samples was 100 Bq/kg or lower. At some distance from the dumped objects the level of radionuclides in sediments was close to the range obtained in the open Kara Sea [2]. It may also be mentioned that the activity of fish from the Baltic, measured in Bq/kg is more than a factor of 10 higher than the activity of fish from the Barents Sea. Thus the contamination caused by the dumped reactor compartments has so far been quite limited. Corrosion of the seawater will of course gradually increase the release of fuel and activated materials to the environment, but at the same time the activity will decrease due to radioactive decay... 

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