What is the duration for which records of dose equivalent received by individuals must be kept?

The correct duration for keeping records of dose equivalent received by individuals is indefinitely. This requirement is based on regulatory standards that emphasize the importance of maintaining a comprehensive record for individuals' exposure to radiation over the course of their careers.

Keeping records indefinitely ensures that there is a permanent account of an individual’s radiation exposure history, which is essential not only for monitoring compliance with safety regulations but also for assessing potential health risks associated with cumulative exposure throughout their lifespan. This is particularly crucial for workers in industries where radiation exposure is a concern, as long-term health effects may not be immediately evident and could manifest years later.

The indefinite retention of these records allows for proper epidemiological studies and health monitoring, should it become necessary in the future. It also facilitates continuity in health surveillance even if an employee changes jobs or retires, ensuring that all relevant exposure information is accessible for ongoing health evaluations.