What is the purpose of the contamination monitor at the exit?

• A. To measure the plant's energy output at the exit.
• B. To detect chemical leaks in the exit corridor.
• C. To monitor worker radiation doses at the exit.
• D. To ensure no radioactive contamination leaves the Protected Area.

Answer: (D)

The main purpose of an exit contamination monitor is to keep radioactive material from leaving the Protected Area. It checks for radioactive contamination on a worker’s skin, clothing, or belongings as they exit. If contamination above the allowed limits is detected, the person is decontaminated or redirected for cleanup before they can leave, preventing the spread of radioactivity to less controlled areas, coworkers, or the public. This protection is separate from other systems that measure plant energy output or detect chemical leaks, and from personal dosimeters that track the radiation dose a worker has received. The exit monitor specifically ensures that no radioactive contamination leaves the controlled zone.