Absorbed dose is the energy imparted by ionising radiation to a volume element of any matter with a certain mass, divided by this mass. The unit of the absorbed dose is J/kg with the special name Gray (short form: Gy).

Weakening of the intensity of a particle or a beam when passing matter. The energy of the irradiation is transformed into another form of energy (e. g. heat). The energy absorbed by biological tissues is the basis for the calculation of the dose absorbed by the organism.

Actinic or solar keratodermas are also referred to as sun calluses. They are disturbed hornifications of the skin caused by solar radiation (corneous or wart-like reddish-brown proliferations). They occur mostly from the age of 50 on and are particularly at places which had been exposed to solar radiation for decades. Mainly fair-skinned persons with skin types I or II who get sunburn easily are affected by this. In dark-skinned persons actinic keratodermas are very rare. Besides men get them more frequently than women do. Actinic keratodermas occur more frequently in persons who as a result of their occupation often stay in the open. Actinic keratodermas are pre-stages of the spinalioma.

Process used to make a material radioactive by bombarding it with neutrons, protons or other particles.

Activity is the number of nuclear fissions per time unit occurring in a radioactive substance. The measure of activity is becquerel (abbr.: Bq) with which the number of radioactive nuclear transformations per second is given.

As radionuclides may be contained in different media (solids, liquids, gases) or adhere to surfaces, the activity is indicated in different ways such as

• mass-related as "specific activity" (e.g. in becquerel per gram (Bq/g)),
• volume-related as "activity concentration" (e.g. in becquerel per litre (Bq/l) or becquerel per cubic metre (Bq/m³)), or
• area-related as "area activity" (e.g. in becquerel per square metre (Bq/m²)).

If the activity is given without relation to mass, volume or area and without stating the radionuclide, it is not possible to make a statement about the radiation exposure.

Rate of activity of a radionuclide to the mass of the material in which the radionuclide is distributed. In the case of solid radioactive substances the reference mass for the determination of the specific activity is the mass of the body or object to which the radioactivity is inseparably connected in an intended application. In the case of gaseous radioactive substances the reference mass is the mass of the gas or gas mixture.

Rate of activity of a radionuclide to the volume of the material in which the radionuclide is distributed.

The activity concentration of the air is given in the unit Becquerel per cubic metre (Bq/m³). The activity concentration of the air states which activity of a certain radionuclide is included in one cubic metre air.

The activity concentration of liquids is given in the unit Becquerel per liter (Bq/l). The activity concentration in liquids indicates how much activity of a particular radionuclide is contained in one liter of a liquid.

Gases with solid or liquid suspended particles. Solid or liquid components of air (diameter: 10^-3 to 10^-8 cm)). The major part of the natural and artificial radionuclides of the air is bound to aerosols.

Portion of cavities in a material filled with air.

A special inbreeding clade showing a high spontaneous leukaemia rate. It is an acknowledged animal model for human leukaemias used in cancer research.

Abbreviation of "as low as reasonably achievable". Principle of radiation protection in the case of ionising radiation according to which all reasonable and sensible measures must be taken to keep radiation exposure to man as low as possible, even below the limits.

Particle radiation in the form of alpha particles. Positive-charged particle emitted in the nuclear disintegration of certain radionuclides. It consists of two neutrons and two protons and is identical with the nucleus of the helium atom. Alpha particles are already absorbed by a few centimetres of air and can neither penetrate a sheet of paper nor human skin. Alpha particles can only have effects on the organism if the substance emitting alpha radiation is inhaled or ingested or enters the body via open wounds. Generally, alpha disintegration is accompanied by gamma radiation. cf. beta radiation, gamma radiation.

Particles produced through radioactive decay, consisting of two neutron and two protons.

Ambient dose equivalent per time interval.

measuring unit of electrical amperage.

Maximum move of a vibration or a wave.

Doctrine of the blood and lymphatic vessels, one of the emphases of internal medicine.

Anonymisation, like pseudonymisation, is a data protection measure. Personal data such as names etc. are changed in such a way that they cannot be assigned to a specific person again, or only with great effort. With pseudonymisation, on the other hand, it is generally possible to assign the data to a specific person.

Device for transmitting or receiving high-frequency electromagnetic waves.

Influenced, caused by man.

A number of different effects under exposure to high-frequency electromagnetic fields occurring independently of a heating of the tissue.

An atom is the smallest particle of an element and chemically not separable. An atom consists of a very dense nucleus and an atomic shell. The main mass of the atom is concentrated in the nucleus in the form of protons (electrically positively charged particles) and neutrons (electrically neutral elementary particles). The atomic shell consists of negatively charged electrons orbiting the nucleus. Atoms are electrically neutral as the number of protons in the nucleus and the number of electrons in the shell is identical.

Act on the peaceful use of nuclear energy and protection against its risks.

Provision of not connected mine openings with air through ventilation tubes and auxiliary fans.

A component of a safety-related system is available, if it is ready in all cases of required operation it has been designed for, e.g. to control design basis accidents, to prevent impermissible plant conditions or impermissible loads of components and systems, and if its functionality has been demonstrated by periodic inspections (cf. definition "periodic inspections"). Non-availabilites of components or systems, which are induced temporarily and in a planned manner by procedures as specified in the operating manual, are not reportable if this is also considered in the safety specification of the operating manual.