part of ISO 18589 specifies the general requirements to carry out radionuclides tests on soil sample, including sampling. This part of ISO 18589 is addressed to people responsible for determining the radioactivity present in soils for the purpose of radiation protection. This may concern soils from gardens and farmland, urban or industrial sites, as well as soil not affected by human activities. This part of ISO 18589 is applicable to all laboratories regardless of the number of personnel or the extent of the scope of testing activities. When a laboratory does not undertake one or more of the activities covered by this part of ISO 18589, such as planning, sampling or testing, the requirements of those clauses do not apply. This part of ISO 18589 is to be used in conjunction with other parts of ISO 18589 that outline the setting up of programmes and sampling techniques, methods of general processing of samples in the laboratory and also methods for measuring the radioactivity in soil. Its purpose is the following: ? define the main terms relating to soils, sampling, radioactivity and its measurement; ? describe the origins of the radioactivity in soils; ? define the main objectives of the study of radioactivity in soil samples; ? present the principles of studies of soil radioactivity; ? identify the analytical and procedural requirements when measuring radioactivity in soil. This part of ISO 18589 is applicable if radionuclide measurements for the purpose of radiation protection are to be made in the following cases: ? initial characterization of radioactivity in the environment; ? routine surveillance of the impact of nuclear installations or of the evolution of the general territory; ? investigations of accident and incident situations; ? planning and surveillance of remedial action; ? decommissioning of installations or clearance of materials. This part of ISO 18589 is not intended to cover scientific investigations of soil radioactivity and therefore does not apply to aspects of such measurements