Radioactive Material Contamination

The laboratory must be aware of the two types of radioactive material contamination:

Fixed Contaminationis that which has become bound by chemical or other means to the surface upon which it was deposited. This form of contamination can only be detected by a survey meter through a radiation area survey. Because it is fixed to the surface, a wipe test will indicate little or no activity. A meter survey may indicate that larger quantities are indeed present on the surface.

Removable Contamination is that which may be wiped off a surface or object, similar to dust on a piece of furniture. The presence of removable contamination is determined by wipe tests and in some situations by the use of a survey meter. If contamination is present in large enough quantities and is removable, it also may be detected by a survey meter when a wipe test of the surface is placed near the probe.