DIN ISO 7503-1:2017-12

Radioactive contamination results from the release of radioactive substances into the environment. In most cases the release is unintentional, but it can also be intentional in certain situations. Although the purpose and scope of investigations may vary, the approaches used to determine the levels and spread of contamination are comparable. Without knowledge of the process or its documentation, it is not always possible to identify or distinguish between the different radionuclides contributing to surface contamination. Therefore, the determination of such contamination often cannot be made on a quantitative basis. It may also be necessary to use other measuring devices that are more suitable for this purpose instead of a measuring device with nuclide calibration. In accordance with national regulations and international agreements, the surface contamination measured in units of activity per unit area shall be compared with the guideline and limit values for surface contamination. Guideline and limit values for surface contamination are nuclide-specific and therefore require complex nuclide-specific calibrations of the measuring instruments. The DIN ISO 7503 (VDE 0493-2) series of standards deals with the measurement and evaluation of surface contamination and consists of the following parts: - Part 1: General principles; - Part 2: Test method using wipe-test samples; - Part 3: Apparatus calibration. This Part 1 of the series of standards deals with the determination of surface contamination by direct measurement with a calibrated surface contamination measuring device and indirect measurement by means of wipe tests. It deals primarily with direct monitoring and practical guidance for making the measurements, and describes principles for ensuring that the measuring instrument is ready for use. Finally, it also describes principles for calibrating the measuring equipment and summarizes the main uncertainties of both methods of determining surface contamination. The responsible committee is DKE/GUK 967.2 "Aktivitätsmessgeräte für den Strahlenschutz" ("Radiation protection instrumentation") of the DKE (German Commission for Electrical, Electronic and Information Technologies) at DIN and VDE.