M16.3
TRANSPORT OF RADIOACTIVE MATERIAL
(Target audience: Persons forwarding Low Specific Activity Materials)
(Mode of transport: Road / Rail / Inland waterway)
Introduction
Transport radioactive material is governed by national and international regulations. The International Atomic Energy Agency (IAEA) has published the Regulations for the Safe Transport of Radioactive Material [1]. All references to “Regulations” in this module pertain to the IAEA Regulations. The objective of the Regulations is to establish requirements that must be satisfied to ensure safety and to protect persons, property and the environment from the effects of radiation in the transport of radioactive material. This protection is achieved by requiring, among others:
a)containment of the radioactive contents; and
b)control of external radiation levels.
These requirements are satisfied first by specifying -
a)performance standards for package design based on the radioactive contents and
b)administrative controls and
c)approval by competent authorities.
Confidence in this regard is achieved through quality assurance and compliance assurance programmes.
Scope of this module
This module relates to the regulatory requirements for the safe transport of low specific activity (LSA) radioactive material by road, rail and inland waterway craft. The LSA material considered in this module are:
a)Ores of uranium and thorium and their physical or chemical concentrates
b)Other ores containing naturally occurring radionuclides which are intended to be processed for the use of these radionuclides
c)Natural uranium, depleted uranium, natural thorium or their compounds or mixtures, that are unirradiated and in solid or liquid form
d)Radioactive material, fissile-excepted, for which the A2 value is unlimited
e)Other radioactive material in which the activity is distributed throughout and the estimated specific activity does not exceed 30 times the Regulatory limits on specific activity for exempt consignment, excluding fissile-excepted material
f)Water with tritium concentration up to 0.8 TBq/L
g)Other solid or gaseous material in which the activity is distributed throughout and the estimated average specific activity does not exceed 10-4 A2 /g and liquids not exceeding the limit of 10-5 A2 /g
h)Solids, excluding powders, of such nature that if the entire contents of a package were subjected to the leaching test prescribed in the Regulations the activity in the water would not exceed 0.1A2 , provided that
(i) the radioactive material is distributed a solid or a collection of solids, or is essentially uniformly distributed in a solid compact binding agent
(ii) The radioactive material is relatively insoluble, or is intrinsically contained in a relatively insoluble matrix, so that, eve under loss of packaging, the loss of radioactive material per package by leaching when placed in water for seven days would not exceed 0.1 A2 and
(iii) The estimated average specific activity of the solid excluding any shielding material, does not exceed 2 x 10-3 A2 /g.
Low specific activity materials described from (a) to (e) are called LSA-I. This group includes natural ores and other materials with a specific activity not exceeding the specified limit.
Low specific activity materials described from (f) and (g) are called LSA-II. This group includes nuclear reactor process wastes which are not solidified, such as lower activity resins and filter sludge, absorbed liquids and other similar materials from all nuclear fuel cycle operations. This could also include many items of activated equipment from the decommissioning of nuclear plants.
Low specific activity materials described in (h) are called LSA-III. This group includes certain types of radioactive waste consignments. In determining the specific activity of an LSA-III material within a solid compact binding agent, the mass of the agent may be included if it is mixed with the radioactive material. If the radioactive material is surrounded by a shielding material, the mass of the shielding material should not be considered in determining the specific activity of the radioactive material.
This moduledescribes how the transport of these materials can be carried out in conformity with the applicable regulatory requirements.
Tasks before the consignor
The consignor should –
a)Familiarize himself with the regulations
b)Select the package in which the radioactive material has to be transported
c)Procure an appropriate package
d)Prepare the package for transport (e.g. load the radioactive material in the package, fasten the closure, decontaminate the exterior of the package)
e)Mark and label the package
f)Conduct the tests before the shipment
g)Complete the transport documents including consignor’s declaration and information to the carrier.
h)Forward the package through a carrier
i)Implement radiation protection requirements and quality assurance
Familiarization with regulatory requirements
IAEA Regulations
The IAEA Regulations [1] form the basis of many national and international regulations for transport of radioactive material.
The Agency has published a Safety Guide advising the user about how the regulatory requirements can be satisfied [2]. In order to guide the consignor through the regulatory requirements, IAEA has published the Schedules for the Regulations as a Safety Guide [3]. The schedules provide specific guidance on the regulatory requirements for each type of consignment.
National Regulations
Transport of radioactive material is governed by national regulations of each State. Member States of IAEA adopt the IAEA Regulations within the frame work of the local laws and the international conventions to which the nation is a party. Accordingly, responsibilities are assigned in the National regulations to consignor, carrier and consignee. Consignors, carriers and the concerned public authorities ensure that the shipments are made in compliance with the applicable national regulations. There could be some differences between the national regulations and the international regulations for the safe transport of radioactive material because of the difference in the legal system among the states.
Regional agreements for modal transport
The transport of dangerous goods by road, rail and inland waterway modes is not covered by an international organization on a worldwide basis. Rather, these are covered by several regional agreements such as:
a)The Regulations Concerning the International Carriage of Dangerous Goods by Rail (RID),
b)The European Agreement concerning the International Carriage of Dangerous Goods by Road (ADR),
c)The European Agreement concerning the International Carriage of Dangerous Goods on Inland Waterways (ADN) and
d)The Regulations for the Transport of Dangerous Goods on the Rhine (ADNR).
e) The MERCOSUR/MERCOSUL agreement
These instruments referred to in (a) to (d) were established in Europe.
The MERCOSUR/MERCOSUL agreement covers road, rail, air and sea transport among certain South American countries.
Definitions of terms
Certain terms are assigned specific meanings in the Regulations. For example the terms contamination means the presence of a radioactive substance in excess of 0.4 Bq/cm2 for beta, gamma and low toxicity alpha emitters or 0.04 Bq/cm2 for other alpha emitters. The term conveyance includes road vehicles, rail cars, vessels or aircraft. A packaging together with the radioactive content is defined as package. Many definitions are provided in the Regulations. It is necessary to understand the meanings assigned to various terms in the Regulations.
A1 values and A2 values
Familiarity with A1 and A2 values defined in the Regulations would be useful. Radioactive material may be transported either in special form (essentially indispersible) and other form. The A1 value refers to the activity of special form radioactive material and the A2 value refers to the activity of other than special form radioactive material. The values of A1 and A2 have been determined for most common radionuclides and are listed in the Regulations.
If the radioactive material is amixture of radionuclides, then the effective A1 or A2 value is calculated thus:
A1 = 1 / [ Σ {f(i)/A1(i)}]
where f(i) of the radionuclide I in the mixture and A1(i) is the A1 value for the nuclide given in the Regulations.
A2 = 1 / [ Σ {f(i)/A2(i)}]
where f(i) of the radionuclide I in the mixture and A2(i) is the A2 value for the nuclide given in the Regulations.
Multiples and fractions of A1 and A2 (for example, 3000A1, 10-3 A1, 3000A2 and 10-4 A2) are used in specifying criteria throughout the Regulations.
Selection of Package
The type of package for the transport of radioactive material is determined by the radionuclide and its activity to be transported.
The Regulations prescribe simple criteria for determining the type of package to be used for the transport of LSA material. Only industrial packages, IP-1/2/3, are required to be used for transporting LSA material. The Regulations provide for transport under exclusive use. Exclusive use means that a single consignor will have the sole use of an aircraft or of a large freight container, in respect of which all initial, intermediate and final loading and unloading will be carried out in accordance with the directions of the consignor or consignee. The consignor has primary responsibility for ensuring compliance. The additional safety afforded by transport under exclusive use is taken into consideration in prescribing the type of industrial package and the contents permitted in the package as can be seen from this table:
Industrial Package requirements for the transport of LSA material
RadioactiveContents / Industrial package type
Not under
Exclusive use / Exclusive use
LSA-I
Solid / IP-1 / IP-1
Liquid / IP-2 / IP-1
LSA-II
Solid / IP-2 / IP-2
Liquid / IP-3 / IP-2
Gas / IP-3 / IP-2
LSA-III / IP-3 / IP-2
If the LSA material contains fissile material, then the Regulatory requirements applicable to fissile material should be complied with.
LSA-I may be transported unpackaged provided that these conditions are met:
a)Under routine conditions of transport, the unpackaged radioactive content should not escape from the aircraft and there should be no loss of shielding. For transport of ores containing only naturally occurring radionuclides this condition does not apply.
b)The shipment should be made under exclusive use.
All other LSA material should be transported only in an appropriate package.
Procurement of an appropriate package
Industrial Packages Type IP-1/2/3 are commonly available in the market. Depending on the group of LSA material that the consignor has to transport, the appropriate IP can be selected from the above table and procured from the market.
Tests before first shipment
Before the first use of a package certain tests have to be carried out.These tests are intended to confirm that the package has been manufactured in complete conformance with the approved design. These tests have to be performed in respect of each manufactured packaging. If the packaging is procured from a vendor, the consignor has to confirm that it has been subjected to these tests and found to be satisfactory.
Following the fabrication of the packaging the effectiveness of shielding should be assessed.
Special arrangement
If conformity with some of the provisions of the Regulations is not practicable, the consignment can be transported but only under special arrangement. Approval for transport under special arrangement should be obtained from the concerned competent authorities.
Approval requirements
The Regulations do not require that any approval be obtained from the competent authority in respect of the package or the shipment for the transport of non-fissile or fissile-excepted LSA material, unless the shipment is to be made under special arrangement. However, if the LSA material is not fissile excepted, competent authority approval should be obtained in respect of the package design and shipment.
Approval of Shipments under Special Arrangement
If the consignment is transported under special arrangement multilateral approval is required. The competent authority needs to be satisfied that the overall level of safety in transport is at least equivalent to that which would be provided if all the applicable requirements of these Regulations had been met.
An application for approval of shipments under special arrangement should include:
a)A statement of the respects in which the shipment cannot be made in full accordance with the applicable requirements and the reasons; and
b)A statement of any special measures which are to be implemented to compensate for the failure to meet the applicable requirements.
Preparation of the package for transport
Limits on package content
The total activity in a conveyance (road, rail vehicle or inland waterway craft) for carriage of LSA material in Type IP-1, Type IP-2, Type IP-3 package or unpackaged should not exceed the limits given in the table below:
The total quantity of LSA material in a single Type IP-1, Type IP-2, IP-3 package should be restricted. The radiation level at 3 m from the unshielded material or object or collection of objects should not exceed 10 mSv/h.
Activity limits for LSA material in industrial packages or unpackaged
LSA group / State of the LSA material / Combustible nature of material / Activity limitRoad, rail vehicle / Inland waterway craft
LSA-I / Solids, liquids and gases / Both combustible and non-combustible / No limit / No limit
LSA-II / Solids / Non-combustible / No limit / 100 A2
LSA-II / Solids / Combustible / 100 A2 / 10 A2
LSA-II / Liquids / Both combustible and non-combustible / 100 A2 / 10 A2
LSA-II / Gases / Both Combustible and non-combustible / 100 A2 / 10 A2
LSA-III / Solids / Non-combustible / No limit / 100 A2
LSA-III / Solids / Combustible / 100 A2 / 10 A2
LSA-III / Liquids / Both combustible and non-combustible / 100 A2 / 10 A2
LSA-III / Gases / Both combustible and non-combustible / 100 A2 / 10 A2
Control of external exposure
External exposure that may result from the transport of radioactive material is controlled.The Regulations imposetwo limits on the radiation level outside the package. One limitrestricts the radiation level at the external surface of the package.The other limit restricts the radiation level at one metre from the external surface of the package. The latter number is referred to as the transport index of the package.
Transport Index (TI)
The TI is an indicator of the radiation level in the vicinity of a package or freight container. It is useful in determining the segregation distances from packages, overpacks and freight containers. The segregation distance is calculated using the inverse square law of reduction of radiation level from package. In the case of large packages radiation levels external to the loads do not decrease as per the inverse square law. Therefore a multiplication factor is introduced for large dimension loads.Segregation distances should be calculated on the basis of the TI indicated on these loads.
Here is the procedure for determining the TI of a package or overpack or freight container:
Determine the TI of a package on the basis of measured radiation levels, considering the package in isolation. Scan the package, including the top and bottom, at a distance of 1 m from the external surface. Ignore protrusions on the exterior of the package in determining the 1 m distance.
For uranium and thorium ores and their concentrates, the maximum radiation level at 1 m from the external surface of the load may be taken as
a)0.4 mSv/h for ores and physical concentrates of uranium and thorium,
b)0.3 mSv/h for chemical concentrates of thorium and
c)0.02 mSv/h for chemical concentrates of uranium, other than uranium hexafluoride.
Multiply these values by 100. The resulting number is the transport index of the package, overpack, freight container or unpackaged LSA-I.
For other LSA material, 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.Multiply it by 100. The resulting number is the transport index of the package / overpack.
For tanks, freight containers and unpackaged LSA-I the transport index thus determined has to be corrected for size of the load by multiplying these values by the appropriate factors given in the table below.
table: Multiplication factors for FREIGHT CONTAINERS
Size of loadaMultiplication factor
size of load 1 m21
1 m2size of load 5 m22
5 m2size of load 20 m23
20 m2<size of load10
aLargest cross-sectional area of the load being measured.
The value obtained above should 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.
Alternatively, the TI for a freight container may be established as the sum of the TIs of all the packages in the freight container.
Many packages may be transported in a rigid overpack or a freight container or an aircraft. The TI,in this case, may be taken as either the sum of the TIs of all the packages contained, or by direct measurement of radiation level. Adding the TIs reflects a conservative approach as the sum of the TIs of the packages contained may be higher than the maximum radiation level at 1 m from the external surface of the overpack or the freight container due to shielding effects and the additional distance from the packages in the core of the consignment.
Limits on T I and Radiation Levels
The transport index of any package or overpack or freight container should not exceed 10. If this limit is exceeded, the consignment could be permitted only under exclusive use.
The radiation level at any point on the external surface of a package or overpack or freight container should not exceed 2 mSv/h. If this limit is exceeded, the consignment could be permitted only under exclusive use.
Exclusive use means that –
a)a single consignor will have the sole use of any vehicle, or hold, compartment, or defined deck area of a vessel or of a large freight container;
b)all initial, intermediate and final loading and unloading will be carried out in accordance with the directions of the consignor or consignee; and
c)the consignor has primary responsibility for ensuring compliance.
For consignments under exclusive use, transported by rail or road the radiation level at any point on theexternal surface of any package or overpack, may exceed 2 mSv/h provided that:
a)the radiation level at any point on theexternal surface of any package or overpack does not exceed 10 mSv/h;
b)the vehicle is equipped with an enclosure which, during routine conditions of transport, prevents the access of unauthorized persons to the interior of the enclosure;
c)provisions are made to secure the package or overpack so that its position within the vehicle enclosure remains fixed during routine conditions of transport; and
d)there is no loading or unloading during the shipment.
For consignments under exclusive use, transported by rail or road the radiation level at any point on theouter surfaces of the vehicle, including the upper and lower surfaces, or, in the case of an open vehicle, at any point on the vertical planes projected from the outer edges of the vehicle, on the upper surface of the load, and on the lower external surface of the vehicle should not exceed 2 mSv/h.