M13.2
TRANSPORT OF RADIOACTIVE MATERIAL
(Target audience: Persons forwarding Surface Contaminated Objects: Mode: Sea)
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 Surface Contaminated Object (SCO) by sea. The SCOs considered in this module are:
a)solid objects on which:
(i)the non-fixed contamination on the accessible surface averaged over 300 cm2 (or the area of the surface if less than 300 cm2) does not exceed 4 Bq/cm2 for beta and gamma emitters and low toxicity alpha emitters, or 0.4 Bq/cm2 for all other alpha emitters; and
(ii)the fixedcontamination on the accessible surface averaged over 300 cm2 (or the area of the surface if less than 300 cm2) does not exceed 4 × 104 Bq/cm2 for beta and gamma emitters and low toxicity alpha emitters, or 4 × 103 Bq/cm2 for all other alpha emitters; and
(iii)the non-fixed contamination plus the fixedcontamination on the inaccessible surface averaged over 300 cm2 (or the area of the surface if less than 300 cm2) does not exceed 4 × 104 Bq/cm2 for beta and gamma emitters and low toxicity alpha emitters, or 4 × 103 Bq/cm2 for all other alpha emitters.
b)solid objects on which either the fixed or non-fixedcontamination on the surface exceeds the applicable limits specified for SCO-I in (a) above and on which:
(i)the non-fixed contamination on the accessible surface averaged over 300 cm2 (or the area of the surface if less than 300 cm2) does not exceed 400 Bq/cm2 for beta and gamma emitters and low toxicity alpha emitters, or 40 Bq/cm2 for all other alpha emitters; and
(ii)the fixedcontamination on the accessible surface, averaged over 300 cm2 (or the area of the surface if less than 300 cm2) does not exceed 8 × 105 Bq/cm2 for beta and gamma emitters and low toxicity alpha emitters, or 8 × 104 Bq/cm2 for all other alpha emitters; and
(iii)the non-fixed contamination plus the fixedcontamination on the inaccessible surface averaged over 300 cm2 (or the area of the surface if less than 300 cm2) does not exceed 8 × 105 Bq/cm2 for beta and gamma emitters and low toxicity alpha emitters, or 8 × 104 Bq/cm2 for all other alpha emitters.
SCOs described in (a) are called SCO-I.
SCOs described in (b) are called SCO-II.
Objects that are radioactive themselves (e.g. activated objects) and are also contaminated cannot be classified as SCOs. Such objects may, however, be regarded as LSA material provided they meet the requirements specified in the LSA definition.
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.
International Maritime Organization (IMO)
The International Maritime Organization (IMO) is a United Nations agency. The regulations, standards and recommendations (IMDG Code) that it has developed, are recognized, followed, and observed by ships of many nations. This code includes provisions for the transport of radioactive material by sea.
In addition, there is the MERCOSUR/MERCOSUL agreement that concerns 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.
Selection of Package
The type of package for the transport of radioactive material is determined by the radionuclide and its activity to be transported.
Some examples of SCO are:
a)parts of nuclear reactors or other fuel cycle equipment that have come into contact with primary or secondary coolant or process waste resulting in contamination of their surface with mixed fission products;
b)objects contaminated only on the external and / or internal surfaces arising from the decommissioning of radiation facilities or nuclear facilities; and
c)objects contaminated only on the external and / or internal surfaces arising from radiation accidents.
The Regulations prescribe simple criteria for determining the type of package to be used for the transport of SCO. Only industrial packages, IP-1/2, are required to be used for transporting SCO. The Regulations provide for transport under exclusive use. Exclusive use means that a single consignor will have the sole use of avesselor 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 SCO
RadioactiveContents / Industrial package type
Not under
Exclusive use / Exclusive use
SCO-I / IP-1 / IP-1
SCO-II / IP-2 / IP-2
SCO-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 vessel 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 except when the contamination on the accessible and inaccessible surfaces is not greater than 4 Bq/cm2 for beta and gamma emitters and low toxicity alpha emitters and 0.4 Bq/cm2 for all other alpha emitters.
c)Where it is suspected that non-fixed contamination on inaccessible surfaces is greater than 4 Bq/cm2 for beta and gamma emitters and low toxicity alpha emitters and 0.4 Bq/cm2 for all other alpha emitters, measures should be taken to ensure that the radioactive material is not released into the vessel.
All other SCO should be transported only in an appropriate package.
Procurement of an appropriate package
Industrial Packages Type IP-1/2 are commonly available in the market. Depending on the group of SCO 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 SCO, unless the shipment is to be made under special arrangement. However, if the SCO 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 vessel for carriage of SCO in Type IP-1, Type IP-2 package or unpackaged should not exceed 100 A2.
The total quantity of SCO 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.
If the SCO contains fissile material, then the Regulatory requirements applicable to fissile material should be complied with.
Control of external exposure
External exposure that may result from the transport of these sources is controlled. The Regulations impose two limits on the radiation level outside the package. One limit restricts 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.
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 SCO-I.Multiply it by 100. The resulting number is the transport index of the package / overpack.
For tanks, freight containers and unpackaged SCO-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.
Multiplication factors for tanks, freight containers and unpackaged SCO-I
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.
Exclusive use means that -
a)a single consignor will have the sole use of any 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.
While under exclusive use, the radiation level on the external surface of the package or overpack or freight container should not exceed 10 mSv/h.
If the radiation level at any point on the external surface of a package or overpack or freight container exceeds 2 mSv/h, it may be transported only under special arrangement.
There is a special case of exception to this requirement. That is, if the radiation level at any point on the external surface of a package or overpack exceeds 2 mSv/h, it may be transported by ship without the need for special arrangement provided the following conditions are met:
a)The packages or overpacks should be carried in a vehicle on board the vessel.
b)The packages or overpacks should be transported in the vehicle under exclusive use conditions as per the regulations for transport by road/rail.
c)The packages or overpacks should not be removed from the vehicle at any time while on board the vehicle.
Controls for Contamination
SCOs are likely to cause the spread of contamination on the package or vessels or storage areas. It is, therefore, good practice to check and confirm that such transfer has not occurred.
The non-fixed contamination on the external surface of any package should be kept as low as practicable. The most effective way to ensure this is to prevent the surfaces from becoming contaminated. It is advisable to check gloves or other items of clothing of personnel routinely handling packages. Under routine conditions of transport non-fixed contamination on the external surface of any package should not exceed the following limits:
a)4 Bq / cm2 for β and γ emitters and low toxicity α emitters and
b)0.4 Bq/cm2 for all other α emitters.
Low toxicity alpha emitters are: natural uranium; depleted uranium; natural thorium; uranium-235 or uranium-238; thorium-232; thorium-228 and thorium-230 when contained in ores or physical and chemical concentrates; or alpha emitters with a half-life of less than 10 days. These limits are applicable when averaged over any area of 300 cm2 of any part of the surface. These limits apply also to the external and internal surfaces of overpacks, fright containers and vessels.
Transport of other goods with radioactive shipment
Only items that are necessary for the use of the radioactive material should be contained in the package.A package should not contain any items other than those that are necessary for the use of the radioactive material. There should be no interaction between these items and the package which could reduce the safety of the package.
If packagings are to be used for the storage or transport of other goods, then the package should first be decontaminatedThat is, the level of contamination should be within these limits:
(a) 0.4 Bq/cm2 for beta and gamma emitters and low toxicity alpha emitters and
(b) 0.04 Bq/cm2 for all other alpha emitters.