How long must each required record of dose equivalent received by individuals be kept?

• A. 5 years
• B. 10 years
• C. Indefinitely
• D. 30 years

Answer: (C)

The main idea is that radiation dose records are kept for the individual's entire life, effectively indefinitely. This is essential because radiation effects, especially stochastic risks, accumulate over a person’s lifetime, and a complete history is needed for accurate health risk assessments, future medical surveillance, and regulatory or compensation purposes. If records were kept for only a fixed time, gaps could occur when a worker changes jobs or retires, making it hard to reconstruct total lifetime exposure. By maintaining these records indefinitely, the dose history stays with the person and remains available whenever needed, across careers and over time.