Occupational radiation exposure

Occupationally exposed persons must be adequately protected from ionising radiation. This includes individual monitoring of the absorbed radiation dose.

Occupational radiation exposure

Occupationally exposed persons means persons who:

in the course of their occupational activities or training may incur exposure which exceeds a dose limit for members of the public:

Effective Dose of 1 mSv / calendar year
Equivalent dose for the lens of the eye of 15 mSv / calendar year
Equivalent dose for the skin of 50 mSv / calendar year
work or undergo training at least once a week in controlled areas

work or undergo training at least once a week in supervised areas and may thus be exposed to an increased ambient dose rate.

Persons aged under 16 years must not be occupationally exposed.

With the new Radiological Protection Ordinance, the definition was extended to also protect persons who are exposed to radiation from natural sources (NORM, radon or aviation). With the exception of aircrew personnel, persons exposed to cosmic radiation are not considered to be occupationally exposed to radiation.

Dosimetry

Dosimetry is the measurement of radiation that is relevant for the assessment of radiation risks. Measurements are taken, for example, using whole-body dosimeters or extremity dosimeters.

The radiation exposure of occupationally exposed persons must be determined individually in accordance with the Dosimetry Ordinance. This is referred to as personal dosimetry. In personal dosimetry, a distinction is made between external and internal radiation exposure:

External exposure:
exposure through equipment such as X-ray devices, computer tomography or through sealed and unsealed radioactive sources. A dosimeter measures the radiation that is emitted onto the surface of the body.

Internal exposure:
radioactive material enters the body through ingestion via the mouth or skin or through inhalation. This is called intake. The activity stored in the body is measured with a thyroid monitor or whole body counter, the excreted activity via the stool and/or urine.

The dosimeter is a measuring device for determining the radiation dose. In personal dosimetry it is carried on the body.