An air sample collected by drawing a known volume of air through a charcoal cartridge is used to measure which form of contamination?

• A. Particulate
• B. Iodine
• C. Tritium
• D. Noble Gas

Answer: (B)

Activated charcoal traps volatile, gaseous contaminants from air by adsorption, so drawing a known air volume through a charcoal cartridge concentrates iodine species (I2 or organic iodides) for subsequent measurement. This makes gaseous iodine the contaminant being assessed. Particulates are captured on a filter rather than charcoal; tritium is usually collected as water vapor or other specific media, and noble gases aren’t effectively retained by activated charcoal, requiring different methods.