Each year about 10 million packages of radioactive materials are transported worldwide by land, sea and air. Radionuclides are used for a variety of purposes e.g. in nuclear medicine, materials testing, oil exploration etc. For these purposes radioactive materials must be packaged and transported to the location of interest. Before these materials can be shipped, care must be taken that the shipping regulations have been strictly followed. The purpose of these regulations, of course, is to ensure safety by containing the radioactivity to make sure that there is no negative effect on the environment, to control the radiation emitted from the package, make sure that nuclear fission criticality conditions cannot be met, and to dissipate any heat generated within the package.
In Germany more than 500,000 packages with radioactive substances are transported annually. Over 90 per cent of these originate not from nuclear power stations, but from hospitals, research establishments, universities and industrial applications. These substances are weakly radioactive and are transported by truck. Waste packages from public or industrial organisations are transported to national collection points in the Federal states. The remaining 10 per cent are highly radioactive, usually spent fuel elements, are transported from nuclear power stations into temporary storage facilities in the direct proximity. In the year 2010, 234 transportations of nuclear fuels were subject to approval. Permission is granted by the responsible Federal Office for Radiation Protection (BfS).
Radioactive material transport has been practiced on a large scale for over 60 years. The first international regulations to cover the safe transport of radioactive material across national borders were those issued by the IAEA in 1961. The underlying principles embodied in those regulations are essentially valid today. They have, however, undergone some revisions (see IAEA GSG-1, 2009) which have been incorportated into national legal frameworks. Radiation protection from transported material requires that the radioactive matieral is well contained and that the external radiation levels are controlled. Further requirements are that there should be no damage caused by heat and that criticality (in the case of fissile mateirals) must be avoided. Radioactive material shipments can range from small amounts of material in cardboard boxes (e.g. radiopharmaceuticals) up to highly radioactive materials in steel drums (e.g. spent nuclear fuel). In order to account for the conditions which packages might experience during transprot, the regulations specify in detail package content limits, radiation levels, labelling and design.
The choice of packaging depends on the radionuclides involved, the amounts of radioactivity to be shipped and the form of the radionuclides. The choice of pacakging also depends strongly on the dose rate (you can have an activity < below 10-3A2 for an excepted package, but if the dose rate is higher than 5 µSv/h in contact with the package, you are obliged to choose a Type A package). Restrictions on the amounts of material are determined by the so-called “A1” and “A2” values. “A1” is the maximum amount of activity for a special form radionuclide that is allowed in Type A packaging, whereas “A2” refers to the maximum amount of activity in a Type A package for other form materials. Usually the A1 or A2 values can not exceed 37 terabecquerels (37 × 1012 Bq) or 1000 curies (Ci). For some materials, however, the limits have been set to 40 TBq or more (in the case of U-238). It is important to note that the A2 values refer to other form radioactive materials and to both external and internal exposure. In contrast to the A1 value, the A2 value assumes that dispersal and contamination of the package content is probable. On this basis, the A2 values are always lower than the A1 values.
A1 and A2 Values
This section is based on the Radioactive Material Regulatory Review, 1998
The primary method to achieve safety in the transportation of radioactive material is the use of proper packaging for the specific radioactive material to be transported. In order to determine the packaging requirements, the following questions should be addressed:
1. What radionuclides are being shipped?
2. What quantity of the radionuclides is being shipped?
3. What is the form of the radionuclide?
- a. Is the material in special form (quantity is compared to A1)?; or
- b. Is the material in other (normal) form (quantity is compared to A2)?
The regulations use the A1 and A2 values as points of reference for quantity limits for each radionuclide. Each radionuclide is assigned an A1 and an A2 value. These two values (in Becquerel or Curie) are the maximum activity of that radionuclide that may be transported in a TYPE A package. The A1 value is the limit of activity for a particular special form radionuclide in a Type A package. The A2 value is the limit for the amount of activity that can be transported in a type A package if the material is not is special form, i.e. “Other form”. The Table above gives examples of A1 and A2 values for a number of typical radionuclides.
The A1 and A2 values are used in the regulations as a normalized measurement of radiological risk for all radionuclides.
Their uses go beyond the activity limits for Type A packages in determining when Type B packages must be used. Other uses involving large multiples of A1 or A2 or different fractions of A1 or A2 include:
• special routing of packages with large quantities
• total activity in packages and conveyances
• designating limits for packages excepted from most requirements
• designating specific activity of contaminated material and associated packaging
(Note: The median accident was defined arbitrarily as one which leads to complete loss of shielding and to a release of 10-3 of the package contents in such a manner that 10-3 of this release material was subsequently taken by a bystander (reference TS-G-1.1 Appendix I.7))
The derivation of the A1 and A2 values in the IAEA regulations is based on a series of dosimetric models, i.e., the "Q-system".
The limiting value for A1 results from worst case assumptions of external direct gamma radiation levels from an unshielded source at a certain distance. Generally the A1 value for a radionuclide is the quantity of that radionuclide that will result in a dose rate of 0.1 Sv/h (10 rem/h) at a distance of 1 metre. Since only external radiation is considered, it is assumed that the radioactive material inside the package will not be dispersed if the package is damaged.
The A2 value, however, is based on the applicability of the most conservative worst case value for five different scenarios, which include the A1 scenario plus external beta radiation to skin, inhalation, ingestion, and external gamma radiation from immersion in a gaseous cloud of material released from a breached package. The five pathways are:
• external gamma radiation
• external beta radiation to the skin
• external gamma radiation from immersion in a gaseous cloud of radioactive material released from a damaged package
As a result of an arbitrary limitation established by IAEA, no radionuclides have been assigned A1 or A2 values greater than 40 TBq (1080 Ci). However, based on their low specific activity and low toxicity, some radionuclides were assigned “unlimited” A1 and A2 values.
As an example, consider the radionuclides Cs-137 and Co-60. The A1 and A2 values are shown in the Table where it can be seen that the values for Cs-137 are quite different and for Co-60 are the same.
Table: Maximum activities for special (A1) and normal form (A2) materials
|Nuclide||A1 (special form)||A2 (normal form)|
|Cs-137||2 TBq||0.6 TBq|
|Co-60||0.4 TBq||0.4 TBq|
|U-238||No limit||No limit|
In the case of Co-60, this means that even if five different exposure pathways are considered, there is no greater risk than if only the external gamma radiation pathway were considered. This is not the case with Cs-137 which does indeed depend on the exposure pathway.
The special form referred to above refers to the fact that if the material were released from the package, the only hazard would be from external gamma radiation. An example of such a special form is that of a sealed (encapsulated) source of radiation. Here the durable metal capsule with high physical integrity ensures that the radioactivity will not disperse. In addition, only solid materials are classified as “special form”. Special form encapsulation is designed such that the capsule cannot be opened unless it is destroyed.
In contrast to special form materials, normal form materials may be solid, liquid, or gaseous. Examples here are waste materials in a plastic bag, a liquid-containing bottle housed with a metal contained, powder in a glass or plastic bottle, contaminated soil in a drum, or gas in a cylinder.
Classification of Packages
To properly understand the basic concepts for safely transporting packages containing radioactive material it is essential to always keep in mind a clear picture of the package components. These are shown in Figure.
Packages of radioactive materials can be classified as follows:
- Excepted package;
- Industrial package;
- Type A package;
- Type B package;
- Type C package.
Excepted packages may only contain limited quantities of radioactive material, which are so small that the potential radiological hazards that might pertain during transport are very low. The requirements for excepted packages can be found in IAEA TS-R-1 620 (and mainly the item 612 which is often forgotten but also 617-619). The radiation level at any point on the surface of an excepted package cannot exceed 5 μSv/h to ensure that any radiation dose to members of the public would be insignificant and that any sensitive photographic material in close proximity would not be damaged.
Industrial packages are used to transport LSA (Low Specific Activity) and SCO (Surface Contaminated Object) material. There are three types of industrial packages (Type IP-1, Type IP-2, and Type IP-3) that are used for LSA and SCO shipments. The requirements that packages have to meet to be classified as industrial packages are not demanding. Many normal packages used in industry, such as steel drums or bins, could meet the requirements. (Note: some IP packages found for chemical products do not satisfy the regulations, since the drop test requires that no more than 20% is lost while for radioactivity, you need to ensure that the confinement is still ok (0% loss))
Type A packages are intended to provide a safe and economical means of transporting a well defined, but significant, minor quantity of radioactive material. A total quantity of up to A1 special form radioactive material, or up to A2 if not special form, may be transported in a Type A package. They are required to maintain their integrity under the kind of abuse or mishandling which may be encountered in normal transport, for example: falling from vehicles, being dropped during manual handling, being exposed to the weather, being struck by a sharp object, or having other packages or cargo stacked on top. The specific tests required for Type A packages simulate such events. Note: the exposure to rain which is described in the regulation is often not correctly understood by manufacturers, which test their package for the rain like any other test. In fact, this test must be done before each other test. This is an important point which is commonly forgotten.
Type B packages: The concept is that it should be capable of withstanding most accident conditions, without breach of its containment or an increase in radiation levels to a point that would endanger the general public and those involved in rescue or clean-up operations. In other words, the package could be safely recovered, but would not necessarily be capable of being reused. While a Type B package is never required to withstand more than one accident, the design criteria imposed by the Regulations subjects the package to a series of mechanical and thermal tests with accumulative effects, each of which must cause the maximum damage. The requirements impose additional necessary design constraints over and above those imposed on packages that meet normal conditions of transport. The outcome of these constraints is to dictate greater structural integrity, more careful consideration of containment features, and the ability to protect from elevated temperatures.
For most modes of transport, a Type B package may contain any quantity of any type of radioactive material up to that allowed by its approval certificate. However, contents limits are applied if the package is transported by air. These limits are 3000 A1 or 100,000 A2 (whichever is lower) for special form material and 3000 A2 for all other forms. Type B packages may either be unilaterally approved (B(U)), or multilaterally approved (B(M)). Type B(U) is approved by one jurisdiction and then accepted elsewhere without further approvals, whereas type B(M) is approved by each country crossed by the shipment. For more information see Regulations for the Safe Transport of Radioactive Material, 2012 Edition, IAEA Safety Standards Series No. SSR-6.
Type C Packages: In recognition of the fact that impact velocities from aircraft crashes can be significantly greater than those from surface modes of transport, the shipment of very large quantities of radioactive material by air requires the use of Type C packages. These are packages that must demonstrate the capability to withstand severe crush, puncture, and fire tests, as well as impact at the high speed of 90 metres/second. These features may all be encountered in a severe air accident.
Finally, note that the package must be done in accordance and conformity with the certificate of the package for excepted, industrial and Type A and conform to homologation certificates for Type B and C.
Classification as an Excepted Package
A package can be classified as excepted provided:
- the package is empty having contained radioactive material
- the package contains instruments or articles in limited quantities as specified in the table
- the package contains radioactive material in limited quantities as specified in the table
- the package contains articles manufactures of natural uranium, depleted uranium or natural thorium
Classification as an Industrial Package
Industrial packages are used to transport LSA (Low Specific Activity) and SCO (Surface Contaminated Object) material. There are three types of industrial packages (Type IP-1, Type IP-2, and Type IP-3) that are used for LSA and SCO shipments. The requirements that packages have to meet to be classified as industrial packages are not demanding. Many normal packages used in industry, such as steel drums or bins, could meet the requirements.
Classification as a Type A package
Type A packages shall not contain activites greater than the following:
- for special form radioactive materials - A1 i.e. A/A1 ≤ 1
- for all other radioactive materials - A2 i.e. A/A2 ≤ 1
- for mixtures of radionuclides the following conditions shall apply to a Type A package:
B(i) is the activity of radionuclide i as special form radioactive material
A1(i) is the A1 value for radionuclide i
C(j) is the activity of radionuclide j as special as other than special form radioactive material
A2(j) is the A2 value for radionuclide j
Activity Limits for Unknown Nuclides
For individual radionuclides or for mixtures of radionuclides for which relevant data are not available, the values shown in the Table shall be used.
Some care should be exercised with the use of this table. In particular with regard to what is meant exactly by an alpha emitter. According to the IAEA definition, article I.59 in "IAEA Safety Standards Advisory Material for the IAEA Regulations for the Safe Transport of Radioactive Material for protecting people and the environment, Safety Series No. TS-G-1.1 (Rev. 1)", of an alpha emitter (for transport purposes):
I.59. A radionuclide is defined as an alpha emitter if in greater than 10–3 of its decays it emits alpha particles or it decays to an alpha emitter. For example, Np-235, which decays by alpha emission in 1.4 × 10–5 of its decays, is not an alpha emitter for the purpose of the special forms consideration. Similarly Pb-212 is an alpha emitter since its daughter Bi-212 undergoes alpha decay.
Dy-152 has a branching ratio of 0.100% for alpha emission. According to the rules given above, it should not be considered as an alpha emitter for transport purposes but as a beta/gamma emitter with an A2 of 20 GBq (rather than the 90 MBq for an alpha emitter).
Other examples of weak alpha emitters which are not classified as alpha emitters for transport purposes are Bi-201 and Bi-203 where the branching ratio for alpha emission is approx 10-6 - 10-7.
The conclusion to this is that care must be exercised when using nuclides in packages which are not in the IAEA Activity limits table. When a nuclide has been added to the package, it should be checked in the Activity limit tab to see if there is an entry. If there is no entry, this means that it is an unknown nuclide. In this case, the user must look up the datasheets for the appropriate nuclear data .
See also Radioactive contents
Radiation and Contamination Limits
For a detailed discussion on radiation and contamination limits the reader should consult the document...
The Transport index “TI” is the highest dose rate accessible during transport in units of µSv/h at a distance of one metre from the external surface of a package containing radioactivity, multiplied by a factor 100. The Transport Index is printed on the label of a package so that interested persons can assess the relative radiation hazard and the control to be exercised upon handling. In special cases (tanks, big containers), an additional multiplication factor must be used.
DETERMINATION OF TRANSPORT INDEX
523. The TI for a package, overpack or freight container, or for unpackaged LSA-I or SCO-I, shall be the number derived in accordance with the following procedure:
(a) Determine the maximum radiation level in units of millisieverts per hour(mSv/h) at a distance of 1 m from the external surfaces of the package, overpack, freight container or unpackaged LSA-I and SCO-I. The value determined shall be multiplied by 100 and the resulting number is the TI. For uranium and thorium ores and their concentrates, the maximum radiation level at any point 1 m from the external surface of the load may be taken as:
(i) 0.4 mSv/h for ores and physical concentrates of uranium and thorium;
(ii) 0.3 mSv/h for chemical concentrates of thorium;
(iii) 0.02 mSv/h for chemical concentrates of uranium, other than uranium hexafluoride.
(b) For tanks, freight containers and unpackaged LSA-I and SCO-I, the value determined in step (a) shall be multiplied by the appropriate factor from Table 7.
(c) The value obtained in steps (a) and (b) shall be rounded up to the first decimal place (e.g. 1.13 becomes 1.2), except that a value of 0.05 or less may be considered as zero.
524. The TI for each overpack, freight container or conveyance shall be determined as either the sum of the TIs of all the packages contained, or by direct measurement of radiation level, except in the case of non-rigid overpacks, for which the TI shall be determined only as the sum of the TIs of all the packages
Package Radiation Limits
LIMITS ON TRANSPORT INDEX, CRITICALITY SAFETY INDEX AND RADIATION LEVELS FOR PACKAGES AND OVERPACKS
529. Packages and overpacks shall be assigned to either category I-WHITE, II-YELLOW or III-YELLOW in accordance with the conditions specified in Table 9 and with the following requirements:
(a) For a package or overpack, both the TI and the surface radiation level conditions shall be taken into account in determining which category is appropriate. Where the TI satisfies the condition for one category but the surface radiation level satisfies the condition for a different category, the package or overpack shall be assigned to the higher category. For this purpose, category I-WHITE shall be regarded as the lowest category.
For radiation limits at 10 cm, see Regulations for the Safe Transport of Radioactive Material 2012 Edition, IAEA, SSR-6, page 52, para 423 (a)
For radiation limits at 1 m, see Regulations for the Safe Transport of Radioactive Material 2012 Edition, IAEA, SSR-6, page 62, para 523 (a)
For radiation limits at 3 m, see Regulations for the Safe Transport of Radioactive Material 2012 Edition, IAEA, SSR-6, page 61, para 517
516. The quantity of LSA material or SCO in a single Type IP-1, Type IP-2, Type IP-3 package, or object or collection of objects, whichever is appropriate, shall be so restricted that the external radiation level at 3 m from the unshielded material or object or collection of objects does not exceed 10 mSv/h.
Package Contamination Limits
REQUIREMENTS AND CONTROLS FOR CONTAMINATION AND FOR LEAKING PACKAGES
507. The non-fixed contamination on the external surfaces of any package shall be kept as low as practicable and, under routine conditions of transport, shall not exceed the following limits:
(a) 4 Bq/cm2 for beta and gamma emitters and low toxicity alpha emitters; and
(b) 0.4 Bq/cm2 for all other alpha emitters.
These limits are applicable when averaged over any area of 300 cm2 of any part of the surface.
MARKING, LABELLING AND PLACARDING
530. For each package or overpack the UN number and proper shipping name shall be determined (see Table 1, page 22 above reference). In all cases of international transport of packages requiring competent authority design or shipment approval, for which different approval types apply in the different countries concerned by the shipment, the UN number, proper shipping name, categorization, labelling and marking shall be in accordance with the certificate of the country of origin of design.
531. Each package shall be legibly and durably marked on the outside of the packaging with an identification of either the consignor or consignee, or both.
532. Each package shall be legibly and durably marked on the outside with the UN marking as specified in Table 9. Additionally, each overpack shall be legibly and durably marked with the word “OVERPACK”.
533. Each package of gross mass exceeding 50 kg shall have its permissible gross mass legibly and durably marked on the outside of the packaging.
534. Each package which conforms to:
(a) An IP-1, IP-2 or IP-3 design shall be legibly and durably marked on the outside of the packaging with “TYPE IP-1”, “TYPE IP-2” or “TYPE IP-3” as appropriate;
(b) A Ty p e A p a c k a g e design shall be legibly and durably marked on the outside of the packaging with “TYPE A”;
(c) An IP-2, IP-3 or a Type A package design shall be legibly and durably marked on the outside of the packaging with the international vehicle registration code (VRI code) of the country of origin of design and either the name of the manufacturer or other identification of the packaging specified by the competent authority of the country of origin of design
536. Each package, overpack and freight container shall bear the labels which conform to the models in Figs 2, 3 or 4, except as allowed under the alternative provisions of para. 541 for large freight containers and tanks, according to the appropriate category. In addition, each package, overpack and freight container containing fissile material, other than fissile material excepted under the provisions of para. 417, shall bear labels which conform to the model in Fig. 5. Any labels which do not relate to the contents shall be removed or covered. For radioactive material having other dangerous properties see para. 506.
537. The labels conforming to the models in Figs 2, 3 and 4 shall be affixed to two opposite sides of the outside of a package or overpack or on the outside of all four sides of a freight container or tank. The labels conforming to the model in Fig. 5, where applicable, shall be affixed adjacent to the labels conforming to the models in Figs 2, 3 and 4. The labels shall not cover the markings specified in paras 529–534.
For more information see Regulations for the Safe Transport of Radioactive Material 2012 Edition, IAEA, SSR-6 page 68.
541. Large freight containers carrying packages other than excepted packages, and tanks, shall bear four placards which conform to the model given in Fig. 6. The placards shall be affixed in a vertical orientation to each side wall and to each end wall of the large freight container or tank. Any placards which do not relate to the contents shall be removed. Instead of using both labels and placards, it is permitted as an alternative to use enlarged labels only, where appropriate, as shown in Figs 2, 3, 4 and 5, except having the minimum size dimensions shown in Fig. 6.
542. Where the consignment in the freight container or tank is unpackaged LSA-I or SCO-I or where a consignment in a freight container is required to be shipped under exclusive use and is packaged radioactive material with a single UN number, the appropriate UN number for the consignment (see Table 1) shall also be displayed, in black digits not less than 65 mm high, either:
(a) In the lower half of the placard shown in Fig. 6 and against the white background; or
(b) On the placard shown in Fig. 7.
When the alternative given in (b) is used, the subsidiary placard shall be affixed immediately adjacent to the main placard, on all four sides of the freight container or tank.
For more information see Regulations for the Safe Transport of Radioactive Material 2012 Edition, IAEA, SSR-6 page 73.
Some examples: Package Labels
Depending on the maximum radiation level at any point on the external surface, packages are assigned to the following categories:
I -WHITE not more than 5 µSv/h at the surface (transport index is 0).
II -YELLOW more than 5 µSv/h but not more than 500 µSv/h at the surface and less than 10 µSv/h at 1 m (transport index is > 0 but < 1).
III -YELLOW more than 500 µSv/h but not more than 2000 µSv/h at the surface and < 10µSv/h - 100 µSv/h at 1 m (transport index is > 1 but < 10).
The category is marked in red (I, II, or III) on the label. The number 7 on each laber refers to a United Nations Class number.
Note that when the TI less than 0.05, it can be set to 0 (IAEA TS-R-1 Table 9 item 527).
Also if the measured values are higher than the limits, possibilities are offered by the regulation, for exclusive use as well as states authorization to approve the transport.
e-Ship++ Web Application
In order to fully understand e-SHIP, some background definitions are required. See for example: Activity limits, A1, A2, Excepted packages, Exemption Levels, Q-system, Transport index, Exemption limit, LL, Authorisation limit, LA
For a more detailed list of definitions, see the Packing glossary Packaging Glossary
See also the Full Glossary
What is e-Ship++?
e-Ship++ (electronic Shipment) is a software program for calculating radiological characteristics of packages for the shipment of radioactive material in accordance with ADR/IATA/IAEA transport regulations.
For package classification purposes and calculating the radiological characteristics for the shipment of radioactive material in accordance with ADR/IATA/IAEA transport regulations, the IAEA Transport Code is not very easy to understand. To address this problem a software tool called e-Ship (electronic shipment) was developed at CERN to assist in the classification of packages for the large number of radioactive sources annually transported by CERN. To make this software tool even more user-friendly, versatile, resilient and widely available, in 2012 CERN granted Nucleonica GmbH permission to transform its e-Ship software into a modern web-based application within the Nucleonica nuclear science portal (www.nucleonica.com). This new web-based application, e-Ship++, allows the user to estimate the radiological impact of the shipment in the event of the release of radioactivity into the environment. For this purpose, data such as the inhalation dose, ingestion dose, external radiation dose (e.g. ambient dose equivalent rate, etc.) are provided. The program has been extended for daily use in the field of radiation protection for estimating additional quantities such as the authorization limit, exemption limit, etc. After intensive beta testing, a stable working version became available in mid-2012. The tool has recently been extended to allow decay calculations taking daughter products into account.
On launching the e-Ship++ application for the first time, there may be no packages in the main My Packages tab. As a first step, the user should transfer the pre-defined packages in Sample Packages to the My Packages. This can be done as follows:
- click on the tab Sample Packages
- select one or more packages by checking the tick boxes
- click on the button Send to My Packages
The selected packages will then appear in the My Packages tab. For more detailed information see Sample Packages.
Thereafter the user can continue with editing the main user interface edit packages
e-Ship++ User Interface
The e-Ship++ application is for the classification of packages for the transport of radioactive material. The user interface is shown in the figure. In the following sections the various tabs - My Packages, Edit, Options, Import, Activity limits, Sample packages, and About e-Ship++ - are described in more detail.
For documentation on the use of the application, the user can click on Help or Getting Started links shown. By clicking on the package names, full details of the individual packages can be seen. The user can also directly create a package manually or import a list of nuclides. This is explained in more detail below.
The My Packages tab contains a list of packages either created by the user or copied from the sample packages. To the right of each nuclide package, the Activity reported or last modified dats are given. The package can also be deleted by clicking on the delete icon (shown in the figure above). At the bottom of the list, the total number of packages is given. The user can also directly create a package manually or import a list of nuclides. By clicking on the Package Name header, the packages can be arranged in ascending / descending order (indicated by the small white triangle).
By clicking on one of the packages (e.g. Simple Package), the full details of the package are shown in the Edit tab as shown below.
The page shows the name of the package together with a short description (optional). Also shown is the Activity reported together with a date picker. This allows the user to specify the date and time at which the activity was reported (e.g. from gamma spectrometry measurements). To the right the package characteristics are shown (material, form, state) together with the host material mass if known. The main table shows the package contents on a nuclide for nuclide basis. The quantities shown are colour coded and classified according to the IAEA/ADR A1, A2, and exemption limits. This classification is shown in more detail in the Options (see below).
At the bottom of the page, the Report button allows the user to generate a report on the package (shown below).
In the grid shown in the Edit tab, the user can select the information to be displayed. There are four basic categories:
General, ICRP, Swiss RPO, IAEA Transport
These are described in more detail in the following sections. At the bottom of the page there is an option to show the source characteristics in the Transport Report.
In the category General the user cam choose to select to show/hide information on MatIndex, Mass, Half-life, and Decay modes taken from the main Nucleonica database.
In the category ICRP the user can choose to select to show/hide information relevant to the individual nuclides such as:
- eing: the dose coefficient (in Sv/Bq) for ingestion.
- einh: the dose coefficient (in Sv/Bq) for inhalation.
=> for further information see Effective dose coefficient.
- Eing(mSv): the committed effective dose equivalent for ingestion. This depends both on the nuclide activity and the dose coefficient through the relation:
=> Eing(mSv) = eing(Sv/Bq) * A(Bq) * 10-3(mSv/Sv)
- Einh(mSv): the committed effective dose equivalent for inhalation. This depends both on the nuclide activity and the dose coefficient through the relation:
=> Einh(mSv) = einh(Sv/Bq) * A(Bq) * 10-3(mSv/Sv)
for further information see Committed effective dose, E
The Swiss RPO values are included in the Options. These are not necessary for radioactive material transportation but are nevertheless useful general quantiites for radiation protection.
In the category Swiss RPO (Swiss Radiological Protection Ordinance) the user can choose to select to show/hide information relevant to the individual nuclides such as:
- LL(Bq): For further information see Exemption limit, LL
- LA(Bq): For further information see Authorisation limit, LA
- A(Bq/g)/LL(Bq/g): the ratio of the nuclide activity to LL.
- A(Bq)/LA(Bq): the ratio of the nuclide activity to LA.
Dose rates: with respect to the application of the operational quantities the ICRU (1993) has stated that h10 is designed for monitoring strongly penetrating radiation, e. g. photons (above about 12 keV) and neutrons, while h0.07 is for monitoring weakly penetrating radiation, e. g. α- and β-particles. Furthermore, h0.07 is also used for monitoring the doses to the extremities from all ionising radiation. See ICRP, 2005
- h0.07 (mSv/h/GBq) @ 10 cm: Dose rate at a depth of 0.07 mm in tissue (directional dose equivalent rate) at a distance of 10 cm from a source of radiation with an activity of 1 GBq (109 Bq). See also Ambient dose equivalent H*(10)
- h10 (mSv/h/GBq) @ 1 m: Dose rate at a depth of 10 mm in tissue (ambient dose equivalent rate) at a distance of 1 m from a source of radiation with an activity of 1 GBq (109 Bq). Definitions from the Swiss regulations page 95. See also Ambient dose equivalent H*(10)
- hc0.07(mSv/h)/(kBq/cm2): Assessment quantity for skin contamination: contamination of 1 kBq/cm2 (averaged over 100 cm2) yields the dose rate (directional dose equivalent rate) indicated.
- Gamma dose rate, H10(µSv/h) @ 10 cm: Actual dose rate at a depth of 10 mm in tissue for a nuclide activity A. The gamma dose rate at 10 cm is obtained from h10 @ 1 m using Gamma dose rate, H10 (µSv/h)@ 10 cm = [h10(µSv/h/MBq) @ 1m] * A(MBq) * 100
Example Ag-111: Activity = 1 MBq, h10(µSv/h/MBq) @ 1m = 0.004, hence,
Gamma dose rate, H10 (µSv/h) @ 10cm = (0.004 µSv/h/MBq) * (1 MBq) * 100 = 0.4 (µSv/h)
This is in good agreement with the value from the Dosimtery & Shielding module which gives 0.393 µSv/h at 10 cm.
Note: Assessment quantities for external radiation [source: Petoussi et al., GSF Report 7/93, National Research Center for Environment and Health, Neuherberg]. If the daughter nuclide has a half-life of less than 10 minutes, the sum of the values for parent and daughter is given.
In the Guidance values CA and CS:
- CA (Bq/m3), Airborne Activity Concentration: CA (Concentration Atmospherique in French) is the guidance value for chronic occupational exposure to airborne activity. Exposure to an airborne activity concentration CA for 40 hours per week and 50 weeks per year yields a committed effective dose of 20 mSv.
For inhalation: CA [Bq/m3] = 0.02 Sv / (einh.2400 m3/year).
CA (or the Derived Air Concentration, DAC) is the average atmospheric concentration of the radionuclide which would lead to the ALI in a reference person as a consequence of exposure at the DAC for a 2000 hour working year. A reference person inhales 20 litres of air per minute or 2400 m3 during the working year. For inert gases, immersion in a semi-infinite hemispherical cloud for 40 hours per week and 50 weeks per year yields an effective dose of 20 mSv (gases and inert gases: D. C. Kocher, Oak Ridge National Laboratory, TN Jnl. 1981, NUREG/CR-1918). In most cases, the CA value relates to the parent nuclide. The exceptional cases where the CA value is given for the daughter nuclide are indicated as such. There are cases where immersion leads to irradiation of the skin or all organs and where the dose resulting from immersion is greater than that from inhalation. In the case of Kr-88, for example, values are given for the daughter nuclide for immersion.
- CS (Bq/m2), Surface Contamination: CS (or Concentration Surfacique in French) is the guidance value for surface contamination outside controlled areas, averaged over 100 cm2. To derive each value, irradiation of the skin, intake and the licensing limit (relation to inhalation) were considered and the most unfavourable case was selected:
– Irradiation of the skin for 8760 hours per year, exhaustion of one tenth of the limit for the skin, corresponding to an effective dose of 0.5 mSv per year.
– Daily ingestion of the activity that may be present on an area of 10 cm2 (parts of the hand), corresponding to an effective dose of 0.5 mSv per year.
– CSinh = LA / 100 cm2 = (5 mSv / [1000. mSv/Sv einh]) / 100 cm2
In the IAEA Transport tab the user can choose to select to show/hide information relevant to the nuclide transport/packaging such as:
- A1, A2: these are the activity limits for Type A packaging for special form (A1) and other form (A2) materials. For more information see A1, A2. Usually A2 is lower than A1.
- Excepted: this is the activity limit for Excepted packages for special and other form materials. Below this limit, Type A packaging is not required.
- Exempt(Bq): below the exempt limit (Bq), the form of the material (special, other) in not important
- Exempt(Bq/g): below the exempt concentraiton (Bq/g) limit, the form of the material (special, other) in not important
- A/A2: the ratio of the nuclide activity to the A2 limit. If this is less than or equal to 1, Type A packaging can be used.
- A/Excepted: the ratio of the nuclide activity to the Excepted limit
- A(Bq)/Exempt(Bq): the ratio of the nuclide activity to the Exempt limit
- A(Bq/g)/Exempt(Bq/g): the ratio of the nuclide activity concentration to the Exempt limit
In the Decay tab, a selected package can be decayed. In the left grid, the original package contents can be seen with creation date (Activity reported). In the right grid, the results of the decay calculations are shown. By default the current date/time are shown together with the decay time in seconds. The original "parents" are shown in the results grid together with any daughters.
e-Ship++ offers the possibility to decay the content of a transport package taking account of the special rules and conventions of the IAEA/ADR. This feature allows the package composition to be monitored from the measurement date to the effective transport date as well as its evolution during the transport. The special rules from IAEA/ADR concern nuclides marked with the notes (a) and (b) in the IAEA/ADR activity limits table (the activity limits table is given in the tab Activity limits) where:
(a): A1 and/or A2 values include contribution from daughter nuclides with half-lives less than 10 days.
(b): Parent nuclides and their progeny included in secular equilibrium.
These rules can best be illustrated with reference to a particular calculation. In the example shown below, a package containing U-238, Cs-137, and U-232 (left grid) is decayed from the activity reported date to the new date. The decay calculation is performed for each nuclide in the original package based on Nucleonica’s Decay Engine. The full results of the decay calculation (with the Show details box checked) are shown in the right grid. The computed decay results are shown in the results (right-most) data grid. With the Show details box checked, the grid shows all nuclides computed by the Decay Engine. Daughter nuclides are reported below the corresponding parent with an inset.
When the Show details box is not checked, the grid results shown below only the details of interest from the point of view of the transport (following IAEA/ADR rules) where nuclides meeting the following conditions have been discarded:
- nuclides marked in “Secular equilibrium” (when parent noted “b”) or
- nuclides having a “half-life less than 10 days” (when parent noted “a”) as well as
- nuclides with a negligible activity (i.e. 0 Bq)
In addition, from the remaining list of nuclides only distinct nuclides are retained. Note that only this “filtered” result can be saved as a new package.
By comparing the above two figures, it can be seen that all stable nuclides have been removed. In addition, the daughters of U-238, being in secular equilibrium with the parent, have been removed according to the ADR/IAEA rules. For U-232, only daughters with zero activity have been removed. For Cs-137, the daughter Ba137m has also been removed according to the ADR/IAEA rules. Notice that when elements such as natural Thorium and Uranium are decay, there is no change in the activity since both assumed in secular equilibrium according (note (b) in the Activity list). For depleted or enriched Uranium the calculation cannot be performed without the isotopic composition. For Rhenium and Rubidium there is also no change in the activity because of the very long half-lives of the primordial nuclides (> 40 Gy).
For more information see Regulations for the Safe Transport of Radioactive Material 2012 Edition, IAEA, SSR-6 Table 2, page 25.
Before a user can upload his/her own nuclide datasets, some rules have to be observed for the data format in these files. At present the input format is kept as simple as possible. The following delimeters are allowed:
The files can be created for example in a spreadsheet, but must be saved as csv files. In the example shown, the nuclide name together with the nuclide activity is shown with a comma , as delimeter. Currently only the activity can be accepted as input.
CERN .txt files: It is also possible to upload dedicated format CERN gamma spectrum files
The Activity limits tab contains the A1 and A2 values together with the activity concentration for exempt material (Bq/kg) and the activity limit for an exempt consignment (Bq). In addition a brief description and notes are given.
Care must be exercised when using nuclides in packages which are not in the IAEA Activity limits table. When a nuclide has been added to the package, it should be checked in the Activity limit tab to see if there is an entry. If there is no entry, this means that it is an unknown nuclide. In this case, the user must look up the datasheets for the appropriate nuclear data .
See section Activity limits for unknown nuclides
The Sample packages tab contains a list of pre-defined sample packages for training and demonstration purposes. One or more packages can be selected using the check boxes in the Select column shown below. Alternatively, all packages can be selected using the Select All button below the grid. Once the packages have been selected, they can be transferred to the user’s packages though the send to My Package buttons. The transferred packages are then available for testing purposes.
My 1st Packages
In this first simple example, a package consisting 1 kBq of Cobalt-60 is created. The activity was reported on 26 May 2016. Default package characteristics are assumed (material, solid, other form). In the nuclide table only the IAEA Transport values are shown for clarity (set in the Options). A host material mass of 150 g was set. The transport report can be generated by clicking on the Report button at the bottom of the page.
The transport report has been generated by clicking on the Report button. The Report is shown in the figure below. At the top of the report a short summary is given of the package characteristics. Thereafter the nuclide source characteristics are given (showing the nuclide, mass, activity, heat generated, and gamma dose rate).
The package characteristics give the main transport parameters (i.e. activity limits) for each nuclide and the entire package. It can be seen that the activities and masses are such that the material is exempt. This is highlighted by the green columns which show that both the A(Bq) / Exempt(Bq) < 1 and that A(Bq/g) / Exempt(Bq/g) < 1. These conditions are required for exempt packages.
Also shown is the gamma dose rate at 10 cm. It is important that this value is < 5 µSv/h - otherwise a Type A package is required.
As part of its validation procedure, the Nucleonica team provides an annual check on the activity limits and other radiological quantities used in the various applications in Nucleonica, in particular e-Ship++. Here we summarise the recent checks for 2013:
ADR 2013: verification and survey of activity limits (A1, A2,…)
The recent check on the ADR 2013 values shows that the activity limits are unchanged in comparison to the ADR 2012 values. The table for activity limits for unlisted nuclides also remains unchanged. The ADR 2013 values agree also with the latest activity limits from the IAEA from 2012 as given in the SSR-6. THE IAEA update is not published every year. The previous update was from 2009.
See our blog post.
Swiss Operational Radiation Protection (RPO) Data for 2018 in Nucleonica
The Swiss Radiological Protection Ordinance (RPO) with status as of 1 January 2018 is now available. As part of its verification procedure, the Nucleonica team provides an annual check on the various quantities listed in this report and used in Nucleonica applications.
See our blog post