Behaviour of decontaminatable coatings prior to and after irradiation with ionizing radiation

Coatings for the floors, walls, ceilings, and components of nuclear installations have been examined with regard to decontamination, colour, glaze, and resistance to chemicals prior to and after irradiation with an energy dose of 0.3 MGy of ionizing radiation. Reproducible results proved to be achievable if sufficient ventilation is provided for during irradiation of the specimens. So the amended version of DIN standard 53 781 permits practice-oriented radiation testing of coatings for nuclear installations (DIN 55 991) only with gamma sources (Co-60, Cs-137) under defined air ventilation at (25±10)0C and with energy dose rates of ≤ 1000 Gy/h (105 rad/h). This high energy dose rate certainly exceeds conditions in practice by some orders of magnitude, but is optimal with regard to costs of testing. (orig./HP)