In order to know if the working surfaces in your laboratory are free of radioactive contamination, a contamination check should be performed after each experiment. This check can be with a survey meter or a wipe test.
Contamination is removable when it can be detected by a wipe test.
Areas with removable contamination should be cleaned and those with non-removable contamination should be covered with the appropriate shielding material, if the radiation levels warrant it, to avoid unnecessary personnel exposure. A guide to radioactive surface contamination limits will be found at the end of this document. The entire laboratory where radioactive material is used must be wipe tested at least once per month. The RSO may recommend different wipe test frequencies depending on the radionuclides and amounts used. Guide for performing a wipe test.