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(Accord relatif au transport marchandises Dangereuses par voies de Navigation intérieures) European Provisions concerning the International Carriage of Dangerous Goods by Inland Waterways (ECE). (MT).

(Accord relatif au transport de marchandises Dangereuses par voies de Navigations intérieures sur le Rhin). Provision concerning the Carriage of Dangerous Goods on the Rhine .

(Accord europeen relatif au transport international des marchandises Dangereuses par Route). European Agreement concerning the international carriage of dangerous goods by road (ECE).

American National Standards Institute
A private, non-profit organisation that administers and co-ordinates the US voluntary standardisation and conformity assessment system.

A1/A2 Values
Under the current IAEA regulations, A1/A2 values are the activity limits for each radioisotope. A1 is the maximum activity of special form radioactive material permitted in a Type A package. A2 is the maximum activity of normal form radioactive material permitted in a Type A package.

Back End

The part of the nuclear fuel cycle, which deals with the fuel after it has been in the reactor. Activities include spent fuel reprocessing, radioactive waste management and disposal and decommissioning of nuclear plants.

The international unit used to measure radioactivity. A becquerel (bq) measures the rate at which decay is taking place. A sample of radioactive material in which radioactive decay takes place each second has an activity of one Bq. It is named after A. Henri Bequerel who first discovered radioactivity in 1896 in uranium salt.

Boiling Water Reactor (BWR)
A light-water reactor in which water that is used as both coolant and moderator is allowed to boil in the core and the resulting steam used directly to drive a turbo-alternator.


Central Commission for Navigation on the Rhine.

Any individual, organisation or government undertaking the carriage of radioactive materials by any mode of transport.

A heavily shielded container used to store/and or ship radioactive materials.

Chain Reaction
A reaction that initiates its own repetition.

Competent Authority
Any national, or international regulatory body or authority designated or otherwise recognised as such for any purpose in connection with IAEA Transport Regulations.

Any package or packages, or load of radioactive material presented by a consignor for transport.

Any individual, organisation or government which receives a consignment.

Any individual, organisation or government, which presents a consignment for transport and is named as consignor in the transport documents.

Methods or physical structure designed to prevent the dispersion of radioactive substances.

Chemical process turning uranium oxide into uranium hexafluoride (UF6) preparatory to enrichment.

Any vehicle or vessel used for transporting radioactive material

Criticality Safety Index (CSI)
CSI is assigned to a package, overpack or freight container, containing fissile material shall mean a number which is used to provide control over the accumulation of packages, overpacks or freight containers containing fissile material.


Dangerous Goods Regulations (IATA).

Dose limits
Principle underlying the basic safety standards that are incorporated into the IAEA Transport Regulations, which provides that doses to individuals shall not exceed the limits for the appropriate circumstances.


United Nations Economic Commission for Europe.

United Nations Economic and Social Council.

Emergency Preparedness
The capability to take actions promptly which will effectively lessen the impact of an emergency on human health and safety, property or the environment.

Emergency Procedures
A set of documents describing the detailed actions to be taken by response personnel in the event of an emergency.

The percentage by weight of the fissile isotope of uranium, U-235, in a mixture of U-235 and U-238. Natural uranium contains about 0.71% U-235. The initial enrichment of light water reactor fuel is about 5% U-235.

Excepted Packages
Packages in which the allowed radioactive content is restricted to such low levels that the potential hazards in case of release are insignificant. Excepted packages must, therefore, meet general design requirements for all packages and other controls during transport and storage, but they are excepted from further design and use requirements.

Fissile Material

Uranium 233, uranium 235, plutonium 239, plutonium 241 or any combination of these radionuclides.

Fuel assemblies
A fuel assembly is an array of fuel rods contained in a regular lattice by means of end grids and spacers, typically of square section with about 15 rods in each side of the outer layer.

Fuel Cycle
All operations associated with the production of nuclear energy including:

Mining and milling, processing and enrichment of uranium
Manufacture of nuclear fuel
Operation of nuclear reactors
Reprocessing of nuclear fuel
Any related research and development activities
All related waste management activities
Fuel pellets
A cylindrical pellet of sintered uranium oxide, typically about 15 mm long and 10 mm in diameter, which is used in the manufacture of nuclear fuel assemblies.

Fuel rod
A long cylindrical tube, typically manufactured from a zirconium alloy, which is filled with a string of fuel pellets and then sealed.

Gamma Ray

High energy, short wavelength electromagnetic radiation emitted from the nucleus. Gamma Radiation always accompanies fission. It is very penetrating and best stopped by thick slabs of concrete lead.

Half Life

The time in which one half of atoms of a particular radioactive substance disintegrates into another nuclear form.

A process, condition or asset which has the potential to adversely impact the health and safety of personnel, the public or the environment.

Health Physics
The science concerned with the recognition, evaluation and control of health hazards which may arise from the use and application of ionizing radiation.

High Level Wastes
Extremely radioactive fission products in spent nuclear fuel and transuranic elements. They may be separated by reprocessing the spent fuel, or the spent fuel containing them may be regarded as high level waste.


International Atomic Energy Agency.

International Air Transport Association.

International Civil Aviation Organization.

International Commission on Radiological Protection.

International Maritime Dangerous Goods Code (IMO).

International Maritime Organization.

Industrial Packages
Used to transport material known as low specific activity (LSA) or surface contaminated objects (SCO). Three types of industrial packages (IP-1, IP-2, IP-3) have been specified. These packages differ as to the degree to which they are required to be capable of withstanding damage. All of the combinations of industrial packaging and respective admissible LSA materials and SCO contents are intended to give the equivalent level of safety. IP-2 and IP-3 must satisfy some test requirements. Many normal packages used in the industry, such as steel drums or bins, could meet the industrial package requirements.

INES (International Nuclear Event Scale)
A simple scale designed by the IAEA for promptly communicating to the public in consistent terms the safety significance of events at nuclear facilities.

INF Code
International Code for the safe carriage of packaged Irradiated Nuclear Fuel (INF), plutonium and high-level radioactive wastes in flasks on board ships (Introduced by the International Martime Organization in 1993 and became mandatory in January 2001)

INF Class 1 Ship
Ship certified to carry INF cargoes with an aggregate activity less than 4,000TBq.

INF Class 2 Ship
Ship certified to carry irradiated nuclear fuel or high level radioactive waste with an aggregate activity of less than 2x106 TBq and ships which are certified to carry plutonium with an aggregate activity less than 2X105 TBq.

INF Class 3 Ship
Ship certified to carry irradiated nuclear fuel or high level radioactive wastes and ships which are certified to carry plutonium with no restriction of maximum aggregate activity of the material.

International computer code for the assessment of the risks of transport operations involving radioactive material for normal and accident conditions.

One or two or more atoms with the same number of protons in the nucleus but a different number of neutrons.


The process of determining whether a practice is overall, beneficial as required by ICRP's system of Radiological Protection, i.e whether the benefits to individuals and to society from introducing or continuing the practice outweigh the harm resulting from the practice.


No glossary entries under 'K' at present


Used to classify packages of radioactive materials. Different labels simplify identification of the packages contents and facilitate control by workers when handling packages.

White label, Category I -
maximum radiation at the surface is not more than 0.005mSv/h and no special handling needed.

Yellow label, Category II -
radiation level at the surface does not exceed 0.5mSv/h and little, if any, special handling is needed.

Yellow label, Category III -
packages with a surface radiation of not more than 2mSv/h as well as higher radiation levels and other packages which require special handling.

White label, "FISSILE" -
this label, in addition to the above three labels, gives handling and storage information related to criticality safety.

Liability for damage caused by ionizing radiation as a consequence of an accident is addressed by the 1963 Vienna Convention on Civil Liability for Nuclear Damage and the 1960 Paris Convention on Third Party Liability in the Field of Nuclear Energy. These instruments determine who is liable, establish minimum amounts of liability and the coverage by some form of financial security, e.g. insurance.

A legal document issued by the regulatory body granting authorisation to perform specified activities e.g. the utilisation of casks for transportation.

Light Water Reactor
A common nuclear reactor cooled and usually moderated by ordinary water.

Low Level Waste
Mildly radioactive or contaminated material, typically from medical or industrial applications of radioactivity, and usually disposed of by incineration and burial.

Low Specific Activity
Radioactive material which by its nature has a limited specific activity or radioactive material for which limits of estimated average specific activity apply.


International Convention for the Prevention of Pollution from Ships (IMO) adopted by the International Conference on Marine Pollution.

A descriptive name, identification number, instructions, cautions, weight specification or UN marks or combinations thereof required by Transport Regulations on outer packaging of hazardous materials.

Uranium is normally mined either using surface (open cut) or underground mining techniques, depending on the depth at which the ore is found.

At the mill, ore is crushed and ground to a fine slurry which is leached in sulphuric acid to allow the separation of uranium from the waste rock.

MOX Fuel
Mixed Oxide (MOX) fuel, made of a mixture of plutonium and uranium oxides. In MOX fuel, the fissile isotopes of plutonium provide the energy that Uranium 235 provides in standard UO2 fuel. Mox fuel can be used in light water reactors.

Multilateral Approval
Approval by the relevant competent authority of the country of origin of the package design, or shipment and each country through or into which the consignment is to be transported. The requirements, however do not apply to a country over which RAM is carried in an aircraft, provided there is no scheduled stop in that country.

Nuclear Fuel Cycle

See fuel cycle.


(Organisation intergovernementale pour les Transports Internationaux Ferroviaires)
International organisation for international carriage by rail.

Principle underlying the basic safety standards that are incorporated into the IAEA Transport Regulations, which provides that, taking economic and social factors into account, all exposures shall be kept as low as reasonably achievable.

Orange Book
The colloquial term for the United Nations "Recommendations on the Transport of Dangerous Goods Model Regulations", so called due to the orange colour of its cover.

An enclosure, such as a box which is used by a single consignor to facilitate as a handling unit a consignment of one or more packages for convenience of handling, stowage and carriage.


A package is the package with its radioactive contents as presented.

The assembly of components necessary to enclose the radioactive contents completely. The nature of the packaging depends on the nature of the material. The packaging may be a high integrity cask, a box, drum, or similar receptacle or a freight container or tank.

A personal computer-based database of the IAEA containing records on current package design, shipment approval certificates, and those certificates that expired within the previous calendar year.

Physical Protection
Procedures for the safeguarding of radioactive materials from acts of theft or sabotage.

A warning sign made of durable material and placed on the exterior sides of a transport vehicle.

There is no isotope for plutonium (Pu symbol) in the natural state. Plutonium 239, a fissile isotope, is produced by the fission reactions in nuclear reactors using Uranium-238.

Pressurised water reactor (PWR)
A light water reactor in which heat is transferred from the core to a heat exchanger via water kept under high pressure so that a high temperature can be maintained in the primary circuit without boiling. Steam is generated in the secondary circuit.

Price Anderson Act
American legislation outlining the methods for compensating nuclear powerplant or nuclear transport accidents. Passed as subsection 170 of the Atomic Energy Act 1954, the Price Anderson Act established a system in which a combination of government guarantees and private insurance coverage would pay claims for personal injury and property damage caused by nuclear accidents.

Quality Assurance

A systematic programme of controls and inspections applied by any organisation or body involved in the transport of radioactive material. Its aim is to provide adequate confidence that the standard of safety prescribed in the IAEA Transport Safety Regulations (TS-R-1) is achieved in practice.


The emission of energy as particles, electromagnetic waves or sound

The emission of radiation resulting from the disintegration of unstable nuclei of atoms

Radiation Protection Programme
Systematic arrangements which are aimed at providing adequate consideration of radiation protection measures.

A series of chemical processes used to separate spent nuclear fuel into its component parts, namely unburnt uranium which can be recycled, plutonium formed in the reactor which is a fissile material and can be recycled as new mixed uranium/plutonium oxide fuel (MOX) and fission product wastes, also formed in the reactor, which have to be conditioned for disposal.

Règlement concernant le transport International ferroviaire des marchandies Dangereuses)
Regulations concerning the International Carriage of Dangerous Goods by Rail (OTIF).


Nuclear safeguards is the term applied to the management of civil nuclear materials to ensure that they cannot be diverted for illicit use and in particular to ensure that proliferation of nuclear weapons cannot occur. The measures include nuclear materials accountancy, containment and surveillance.

International Convention for the Safety of Life at Sea.

The specific movement of a consignment form origin to destination.

The person (or agent) who tenders a shipment for transport. The term includes persons who prepare packages for shipment and offer packages to a carrier for transport by signature on the shipping paper.

Shipping Documents
Documents accompanying a shipment of radioactive materials which must include the following information: shipping name, hazard class number 7, identification number, identity of radionuclides contained in the package, description of the physical and chemical form of the material, total activity of the radioactive content, category of label on the package, and type of package.

Special Form Radioactive Material
Can be either an indispersible solid radioactive material or a sealed capsule containing radioactive material.

Spent fuel
Spent fuel is the irradiated fuel discharged at the end of its useful life from a nuclear reactor. This occurs because after about 3 years chemical, physical and nuclear changes render the fuel no longer efficient in maintaining a nuclear chain reaction and generating heat.

Surface Contaminated Object (SCO)
A solid object which is not in itself radioactive but which has radioactive material distributed on its surface.


Technical Instructions for the Safe Transport of Dangerous Goods by Air (ICAO).

The safety of nuclear fuel cycle transport depends primarily on the design of the package rather than on operational control, and the types of packages are defined according to the radioactivity and physical form of the materials they contain. Appropriate mechanical tests related to impacts, thermal tests related to fires, and tests related to the effects of contact with water are specified in the IAEA Regulations.

Transport Index
A number assigned to a package, overpack or freight container, which is used to provide control over radiation exposure. The value of the transport index for a package or overpack is used in determining the category:
I - White
II - Yellow
III - Yellow
to which the package or overpack belongs and, hence, which requirements are applicable to its transport.

Transport Safety Standards Committee (TRANSSC)
A standing body of regulatory officials with experience in radioactive materials transport safety. It provides advice to the IAEA secretariat on the overall programme on regulatory aspects of transport safety and has a primary role in the development and revision of the IAEA transport safety standards.

Type A Packages
Intended to provide a safe and economical means to transport relatively small, but significant, quantities of radioactive material. The total activity of their contents is appropriately limited, depending on whether they are in unspecified form, or comply with the requirements of special form. They are required to maintain their integrity under the kinds of abuse or mishandling which may be encountered in normal conditions of transport, say, for example, falling from vehicles, dropped during manual handling, exposed to weather, struck by a sharp object, or having other packages or cargo stacked on top. They are, therefore, submitted to a water spray test, a free drop test, a stacking test and a penetration test.

Type B Packages
Used to carry larger amounts of radioactive material than Type A packages. The Type B package must withstand the same normal transport conditions as the Type A package, but it must also be capable of withstanding accident conditions, without breach of its containment or an increase in radiation to a level which would endanger the general public or those involved in rescue or clean up operations. Type B packages are submitted to a series of stringent tests for resistance to impact, penetration, fire and water immersion.

Type C Packages
A more robustly designed package, used for the air transport of high activity materials. Such packages must be designed to withstand Type A tests for normal transport conditions. Regarding accident transport conditions, they are submitted to test sequences including a drop test, a puncture/tearing test, an enhanced thermal test, an enhanced water immersion test and an impact test at a speed of 90m/s. Type C packages have not yet been developed.


Universal Postal Union

Unilateral Approval
An approval of a design which is required to be given by the Competent Authority from which the package design originated.

A chemical element (U symbol). Natural uranium occurring in rocks, water and ore, consists of three main isotopes; Uranium 238, Uranium 235 and Uranium 234. Uranium 235 is the only natural fissile nuclide, an outstanding property that explains its use as an energy source.

Uranium Hexafluoride (UF6)
A uranium of flourine compound. Uranium hexafluoride has the property to move from solid state to a liquid or gaseous state by small temperature variations. It is used most of the time in its gaseous state in industrial processes to enrich uranium in the uranium-235 isotope.

Uranium Ore Concentrate
Uranium ore extracted from the mine, which has undergone nearby a chemical process to produce concentrates in the form of powder or a paste. They contain about 75% uranium or 750kg per metric ton. These concentrates, generally known as "yellow cake" because of their colour, are then shipped from mines to UF6 conversion facilities.


Vitrification incorporates fission products into a stable glass matrix. The glass then is poured into a stainless steel canister, where it solidifies. The fission products then form an integral part of a stable, compact and resistant glass. The vitrification process allows the definitive immobilisation and confinement of the fission products in a form suitable for final disposal.

Vitrified residue
Residue (fission products) locked in a solid matrix by virtue of the vitrification process. The fission products have been incorporated into glass and are a complete part of the glass in which they are immobilised.

N / A

No glossary entries under 'W' at present

N / A

No glossary entries under 'X' at present

N / A

No glossary entries under 'Y' at present

N / A

No glossary entries under 'Z' at present

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