What are the steps in a routine wipe test and how are the results interpreted?

• A. Wipe sample collected from surface; measured for radioactivity; compare to release criteria or registrant limits to determine contamination.
• B. Wipe sample collected; never measured; always considered contaminating.
• C. Wipe sample is used to check air humidity; interpret accordingly.
• D. Wipe results are only used for routine cleaning decisions; not for contamination assessment.

Answer: (A)

A routine wipe test is about quantifying surface contamination and making a pass/fail decision based on established limits. The process starts with collecting a wipe from a defined surface area using a consistent method, then measuring the activity on the wipe with an appropriate instrument. The measured activity is corrected for counting efficiency, background, and the area of the wipe, and then expressed as activity per area (for example, dpm or Bq per 100 cm^2). This value is compared to release criteria or registrant limits to determine whether contamination is present and whether any action, such as decontamination or further monitoring, is needed. If the result is below the limit, the surface is considered acceptable; if it exceeds the limit, corrective steps are required.

Other statements don’t fit because a wipe test is not about never measuring the wipe, it is about measuring exactly what is on the surface. It is not a check of air humidity, and the results are not used only to guide routine cleaning without regard to contamination—these results are specifically used to assess contamination against defined limits.