Reference levels and dose limits
Various criteria have been adopted to support decision-making on the protective measures that may be required for disaster control. The aim is to limit individual dose and minimise the late effects of radiation exposure.
The Basic Radiological Principles define the intervention reference levels to be applied in disaster control. In accordance with section 94 StrlSchG, dose values from the BMU are set out in legislative ordinances.
|Measure||Intervention reference levels|
|Organ dose (thyroid gland)||Effective dose||Integration times and exposure pathways|
|Sheltering||-||10 mSv||External exposure and committed effective dose due to inhaled radionuclides as a result of permanently staying outdoors for a period of 7 days.|
|Taking iodine tablets||-||Committed equivalent dose due to radioactive iodine inhaled over a period of 7 days as a result of remaining permanently outdoors.|
|Evacuation||-||100 mSv||External exposure and committed effective dose due to radioactive iodine inhaled over a period of 7 days as a result of remaining permanently outdoors.|
In an emergency, protection and monitoring measures appropriate to the situation should aim to ensure that exposure of emergency personnel in the exposure situation is kept below the reference value as far as appropriate after taking account of all circumstances surrounding the emergency. In principle the values which are set out as limit values in planned exposure situations in section 55 of the Radiation Protection Ordinance are to be used as reference values. The effective dose is 20 millisieverts, organ equivalent dose for the eye lens 150 millisieverts and 500 millisieverts each for the organ equivalent dose for the skin, hand, foot, underarm and ankle. The sum of all doses from all deployments during the emergency exposure situation must be compared to the reference values. Exposure of emergency workers is also classed as occupational exposure (section 3 (2) (31) Radiation Protection Ordinance - StrlSchV).
Where deployment serves to protect human life and health and one of the above mentioned reference values cannot be complied with despite appropriate protective and monitoring measures, the aim is to ensure that exposure of emergency personnel does not exceed the reference value for an effective dose of 100 millisieverts (for volunteers 250 to 500 millisieverts is also possible in exceptional cases). Personnel which have already been exposed to an effective dose exceeding 250 millisieverts in an emergency or which have already reached their dose limit of 400 millisieverts for an entire working life pursuant to section 56 StrlSchV should, if possible, not be deployed again for the aforementioned exceptional cases.
Personnel must be adequately informed of the health risks associated with each deployment and the protective and monitoring measures to be taken. Pregnant women and people under the age of 18 should not be deployed in such situations.