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Englischsprachiges Glossar

Abandon, toshow / hide

Taking out of operation mine openings no longer needed.

Abschalungenshow / hide

German term for rock scaled off the cavity contour of a mine cavity.

Absorbed dose show / hide

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).

Absorption show / hide

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.

Accident show / hide

Sequence of events which may result in an effective dose of more than 50 mSv for one or more persons.

Actinic keratodermas show / hide

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.

Activationshow / hide

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

Activityshow / hide

Activity is the number of nuclear transformations occurring per time unit in a radioactive substance. The measuring unit of activity is Becquerel (short symbol: Bq) with which the number of radioactive nuclear transformations per second is given.

As the radionuclides can be included in amounts of substance of different configuration, the activity is frequently also referred to them, e. g.

  • Becquerel per gram (Bq/g) in solid substances,
  • Becquerel per litre (Bq/l) in liquids or
  • Becquerel per cubic metre (Bq/m³) in air.

Solely stating the activity without knowing the radionuclides does not allow a statement on the radiation exposure.

Activity, specific show / hide

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.

Activity concentrationshow / hide

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.

Activity concentration of the airshow / hide

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.

adjoining rockshow / hide

Rock layers located on the sides outside the salt structure.

Aerosolshow / hide

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.

aerosolsshow / hide

Gases with solid or liquid suspended particles. The major part of the natural and artificial radionuclides of the air is bound to aerosols.

Air show / hide

Mine air.

air boxshow / hide

Tube, e.g. for transporting air.

Air box, ductshow / hide

Tube for transporting an air split

air bratticeshow / hide

Brattice to direct air flows underground (ventilation).

air lockshow / hide

Serves to specifically distribute air flows underground.

air pipeshow / hide

Tube for transporting air flows underground.

air pore volumeshow / hide

Portion of cavities in a material filled with air.

AKR mice show / hide

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

ALARA show / hide

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.

Alpha radiation (alpha particles)show / hide

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.

Alpha-ray emittershow / hide

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

Ambient dose equivalent H*(10)show / hide

Dose equivalent at a point in a radiation field, that would be produced by the corresponding expanded and aligned field in the ICRU sphere at a depth of 10 mm on the radius vector opposing the direction of the aligned field. The unit of H*(10) is J/kg with the special name Sievert (Sv).

Ambient dose rate show / hide

Ambient dose equivalent per time interval.

Ampere show / hide

measuring unit of electrical amperage.

Amplitude show / hide

Maximum move of a vibration or a wave.

Angiology show / hide

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

Anthropogenic show / hide

Influenced, caused by man.

Athermal effects show / hide

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

Atom show / hide

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.

Auxiliary ventilationshow / hide

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

Availabilityshow / hide

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.

Working Group for the Selection of Repository Sites (AkEnd)show / hide

There has been no repository for spent fuel elements from nuclear power plants and for high-radioactive waste from reprocessing world-wide. In Germany, the Gorleben salt dome was investigated since 1978 for its suitability as a repository for all types of radioactive waste. The Federal Government, however, doubts the Gorleben site's suitability. In consultation with the utilities it therefore interrupted the investigation on 1st October 2000 for a period of three to maximum ten years in order to clarify conceptual and safety-related questions (moratorium). The federation does not see any alternative to disposal in deep geological formations for the long-term safe disposal of radioactive waste. Therefore the Federal Government will search further sites in different rock formations for disposal and investigate them for their suitability.

The question results how sites can be identified which are suitable for a safe disposal and are at the same time accepted by the general public. Against this background the Federal Ministry for the Environment, Nature Conservation and Nuclear Safety (BMU) established the Working Group for the Selection of Repository Sites (Arbeitskreis Auswahlverfahren Endlagerstandorte, AkEnd) in February 1999. The recommendations of the AkEnd serve to support the federation in the execution of its tasks to erect facilities for the disposal of radioactive waste according to § 9a para. 3 Atomic Energy Act (AtG).

The AkEnd is a scientific body working independently and free of directions and orders within the scope of the objectives aimed at. When appointing persons for the AkEnd, BMU observed a fair balance regarding persons and institutions, so that a wide spectrum of opinions on the issue of disposal existing among experts is represented. The members of AkEnd are experts in the fields of geosciences, social sciences, chemistry, physics, mathematics, mining, disposal technology, engineering, and public relations.

The AkEnd has the task to develop a comprehensible procedure for searching and selecting sites for the disposal of all types of radioactive waste in Germany. The procedure should in an appropriate form provide for involvement of the public and include well-founded criteria. The development should be made on a scientific basis in a way that is oriented towards facts, unprejudiced and without excluding relevant aspects, taking into account the procedures and experiences made in other countries. The AkEnd should discuss its considerations already in the process of their development with national and international experts and the interested public.

© Bundesamt für Strahlenschutz