DIN 25413-1:2013-04

The proportions of elements for concretes provided in this document apply for design calculations for concrete shields with a large radiation attenuation factor in nuclear power stations, research reactors and at other sources of intensive neutron radiation. When using this document for design calculations with low radiation attenuation factors it shall be considered that the mean distribution of proportions of elements for the different concretes specified in this document is only safeguarded for concrete shields with a large attenuation factor. Therefore, it is recommended in these cases to determine and evaluate the attenuation factors for the specified extreme values of the proportions of elements. The specified values shall facilitate calculations which generally result in lower levels of imprecision stemming from deviating proportions of elements in the raw materials than are made up by the preparation-dependent deviations of the concrete's bulk density and the water and iron proportion. The heat release or activation caused by the neutron field and secondary gamma radiation in the shield are not covered in this document. The committee responsible for this standard is NA 062-07-34 AA "Abschirmungen" ("Shielding") at DIN.