I.-Distributors, suppliers and producers of natural materials or industrial residues likely to cause exposure to gamma radiation in excess of the reference level laid down in article R. 1333-38 must provide users of these natural materials or industrial residues with the mass concentrations of natural radionuclides present obtained by radiological characterisation.
II – The radiological characterisations provided for in I are carried out by bodies accredited by the French Accreditation Committee or by another member body of the European Cooperation for Accreditation that has signed multilateral mutual recognition agreements under the conditions laid down by an order of the Minister responsible for radiation protection.