[en] The choice of decontamination method depends on the surface character. Contaminated particles may stick to the surface mechanically or may be bound by the surface. In the former case, decontamination can consist in sucking off solid particles, washing or rinsing, or in removing using special lacquers. In the latter, chemical methods can be used, such as wetting, applying decontamination solutions or using a steam ejector or injector, or mechanical methods can be used. Mechanical decontamination may consists in grinding and dry, vacuum, wet, or mechanical blasting. Decontamination can be effected to advantage using combined methods. In this, the mechanical method follows the chemical method and its objective only is to increase the efficiency of the latter. Of combined methods, the use of ultrasound and electrolysis are discussed. (J.P.)