What device is used to measure radioactive contamination on surfaces?

• A. Frisker
• B. Dosimeter
• C. Geiger counter
• D. Spectrometer

Answer: (A)

Surface contamination is checked with a frisker because it’s built to detect and quantify radioactive material present on surfaces. A frisker is a handheld contamination monitor that scans floors, countertops, equipment, and other surfaces to reveal removable or contributing contamination levels, guiding cleaning and decontamination efforts. It provides a count rate that directly reflects how much contamination is present on the surface, which is what you need for compliance checks and to determine when an area is safe.

A dosimeter, on the other hand, measures the dose of radiation that a person receives over time. It isn’t designed to tell you whether a surface is contaminated, just how much radiation exposure the wearer has accumulated. A Geiger counter measures general radiation levels in the environment or on a surface, but it doesn’t specifically indicate surface contamination or identify whether the radiation comes from contamination on the surface versus ambient sources. A spectrometer identifies which isotopes are present by analyzing energy spectra, which is more for identifying sources than performing routine surface contamination surveys.