Parties engaged in aviation operations must investigate if there is any cause to suspect, that the annual effective dose of an individual worker may exceed 1 mSv. In practice, this applies to all parties engaged in aviation operations at altitudes of more than 8000 meters. The responsible party must implement the radiation protection of aircrews in accordance with the requirements presented in STUKs regulation STUK S/3/2019. An appropriate calculation programme of proven reliability must be used for determining exposure to cosmic radiation. Reliability may be demonstrated, for example, by means of international comparisons. The calculation programme must be: 1) suitable for determining cosmic radiation doses; 2) validated according international standards or in other suitable and documented way and 3) sufficiently accurate: the computed ambient dose equivalent/ambient dose equivalent rate may not deviate by more than +- 30 % from the measured or reference value. Examples of calculation programmes of proven reliability are CARI, EPCARD and FREE. Aircrew doses are calculated by airline companies.
Whole body measurements concern the energy range of 50-2000 keV. Thyroid measurements are dedicated to iodine isotopes. Internal dose is determined directly using HPGe detectors.
Activities of tritium, strontium, transuranium, uranium, polonium and lead are measured from urine samples.
Calculation of the dose is done either by using a suitable function/dose reduction factor or dose calculation program. Dose range varies depending both on the nuclide and the measuring method used.
A recording level of 0.1 mSv is used for internal committed dose.
Radon measurement methods are approved by STUK. The requirements for the measurement method are represented in STUK’s regulation STUK S/3/2019. A list of the approved radon measurement methods (in Finnish) is in STUK's webpages.