External dosimetry

The goal of external dosimetry is to evaluate the effective dose and the average equivalent dose to exposed tissues. The main advantages of the personal dosimetry are:

  • confirmation of the proper methodology in specific workplaces
  • as a means for finding new methodologies in the workplaces for each worker individually or groups of workers
  • provision of data in case of an incident/accident
  • provision of data for medical and legal purposes
  • provision of data for epidemiology studies

Employees who are professionally exposed to ionizing radiation, for supervision and monitoring purposes, are classified as follows:

  • category A: those exposed workers who are liable to receive an effective dose greater than 6 mSv per year or an equivalent dose greater than 15 mSv per year for the lens of the eye or greater than 150 mSv per year for skin and extremities;
  • category B: those exposed workers who are not classified as category A workers.

In the greek legislation a specific type of occupationally exposed workers is mentioned, namely the outside workers. Outside worker is any Category A exposed worker who is not employed by the undertaking responsible for the supervised and controlled areas, but performs activities in those areas, including, apprentices and students;.
The results of the dose measurement to external sources, which are performed either on a monthly or a bimonthly basis - for photons and neutrons respectively - are recorded to the National Dose Registry kept by EEAE.

At the same time, the values of the effective dose of aircrew personnel, which are calculated by the airline companies, are sent to the Personal Dosimetry Department in order to be recorded to the National Dose Registry.

Today, the numbers of the monitored personnel using the various dosemeters are as follows:

  • 11.000 workers with whole body dosemeters
  • 50 workers with wrist dosemeters
  • 50 workers with neutron dosemeters
  • 200 workers with gamma radiation ring dosemeters
  • 120 workers with mixed beta/gamma radiation ring dosemeters
  • 250 workers using whole body dosemeters inside the protective apron
  • 50 workers with eye lens dosemeters