Which type of contamination is typically more easily removed from surfaces?

• A. Fixed contamination
• B. Discrete radioactive particles
• C. Internal contamination
• D. Loose contamination

Answer: (D)

The key idea here is how tightly the contaminant is attached to the surface. Loose contamination sits on the surface and isn’t strongly bound, so it can be lifted away with simple cleaning methods like wiping, rinsing, or using a mild detergent. This makes it relatively easy to remove compared with contaminants that are more firmly attached.

Fixed contamination, on the other hand, is bonded more tightly to the surface or has penetrated into pores or coatings. It resists ordinary cleaning and may require more aggressive methods or special decontamination procedures to reduce it. Internal contamination isn’t on the surface at all—it’s inside the body—so it can’t be removed from surfaces. Discrete particles could be removable if they aren’t firmly embedded, but the typical, most readily removed form is loose contamination.