M8.2
TRANSPORT OF RADIOACTIVE MATERIAL
(Target audience: Consignors of Radioisotopes of Large Activity - Mode: Sea)
Scope of this module
This module relates to the regulatory requirements for the safe transport of radioactive material by sea to –
a)hospitals for treatment of cancer (telegamma therapy and brachytherapy)
b)radiation sterilization facilities for sterilizing single use medical supplies, such as syringes, gloves, cotton and bandages
c)food irradiation facilities for prevention of infestation and preservation of food
d)blood irradiation facilities used in life-saving blood transfusion as it reduces the risk of immunological reaction in the recipient
e)facilities handling self-shielded irradiators
f)radiation detector calibration facilities
g)industrial radiography institutions and
h)oil well logging facilities.
This module also includes transport of fresh cobalt-60 rods from nuclear reactors to hotcells preparing the sources for various applications.
This module describes how the transport of these materials can be carried out in conformity with the applicable regulatory requirements.
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;
b)control of external radiation levels; and
c)prevention of damage caused by heat.
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.
Tasks before the consignor
The consignor should –
a)Know the regulations
b)Ensure that a radiation protection programme and a quality assurance programme are in place and implemented
c)Select and procure an appropriate package in which the radioactive material has to be transported
d)Obtain the necessary approvals from the concerned competent authority/authorities
e)Fulfil the requirements, in particular, instructions for use, as stated in the package design approval certificate
f)Prepare the package for transport (e.g. load the radioactive material in the package, seal the package, check the radiation and contamination levels)
g)Mark and label the package
h)Undertake the appropriate measures and tests before each shipment as outlined in the package design approval certificate and the requirements of the regulations (TS-R-1)
i)Complete the transport documents
j)Forward the package
Regulatory requirements
IAEA Regulations
The IAEA Regulations [1] form the basis of many national and international regulations for transport of radioactive material. The assignment of responsibilities to consignor, carrier and the consignee would be determined by the laws and customs of different countries and the international conventions into which the countries have entered.
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. 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 national and 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.
Other dangerous properties of contents
If the radioactive material contained in the package has any other dangerous properties, such as explosiveness, flammability, pyrophoricity, chemical toxicity and corrosiveness, the package should be transported in compliance with the relevant transport regulations for dangerous goods of each of the countries through or into which the materials will be transported. In addition, the regulations of the concerned transport organizations should also be complied with.
Radiation protection requirements and quality assurance
Establishment of a Radiation Protection Programme
A Radiation Protection Programme (RPP) should be established for the transport of radioactive material. The nature and extent of the measures to be employed in the programme should be related to the magnitude and likelihood of radiation exposures. The RPP documents should be made available, on request, for inspection by the relevant competent authority. A sample RPP is given in appendix 1.
For occupational exposures arising from transport activities, where it is assessed that the effective dose may exceed:
(a) 1 mSv but not exceed 6 mSv in a year, workplace monitoring or individual monitoring should be conducted to assess the dose;
(b) 6 mSv in a year, individual monitoring should be conducted.
When individual monitoring or workplace monitoring is conducted, appropriate records should be kept. The Agency has published a Safety Guide on Radiation Protection Programmes for Transport of Radioactive Material [5].
Emergency preparations
In the event of accidents or incidents during the transport of radioactive material, emergency provisions, as established by relevant national and/or international organizations, should be observed to protect persons, property and the environment..The Agency has published a Safety Guide emergency preparedness for transport accidents.[6].
Training of personnel
Workers directly engaged in any activity involving packages containing radioactive material should receive appropriate training concerning radiation protection.
Persons engaged in the transport of radioactive material should receive training in the contents of the Regulations commensurate with their responsibilities.
Individuals such as those who classify radioactive material; pack radioactive material; mark and label radioactive material; prepare transport documents for radioactive material; offer or accept radioactive material for transport; carry or handle radioactive material in transport; mark or placard or load or unload packages of radioactive material into or from transport vehicles, bulk packagings or freight containers; or are otherwise directly involved in the transport of radioactive material as determined by the competent authority; should receive the following training:
(a) General awareness/familiarization training:
(i) The general provisions of the Regulations;
(ii) Description of the categories of radioactive material; labelling, marking, placarding and packaging and segregation requirements; a description of the purpose and content of the radioactive material transport document; and a description of available emergency response documents;
(b) Requirements which are specific to the function that person performs;
(c) (i) Methods and procedures for accident avoidance;
(ii) Emergency response information and how to use it; and
(iii) Risk posed by the various categories of radioactive material and measures to prevent exposure.
Records of all safety training undertaken should be kept by the employer and made available to the employee if requested.
The training required above should be provided upon employment and should be periodically supplemented with retraining as deemed appropriate by the competent authority.
Quality Assurance
Quality assurance programmes should be established and implemented for transport operations. They should be based on international, national or other standards acceptable to the competent authority. This will ensure compliance with the Regulations. Certification that the design specification has been fully implemented should be available to the competent authority. The consignor should be prepared to demonstrate to the competent authority that all packagings are periodically inspected and, as necessary, repaired and maintained in good condition so that they continue to comply with all requirements even after repeated use.
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.
Selection of Package
The type of package for the transport of radioactive material is determined by the radionuclide and its activity to be transported. Let us consider the following typical examples of radioactive materials considered in this module.
Table: Examples of large radioactive sources transported
Radionuclide / Use of the radioactive material / Typical activity(TBq) / A1
(TBq) / A2
(TBq)
Cobalt-60 / Telegamma therapy / 400 / 0.4 / 0.4
Cobalt-60 / Brachythrapy / Industrial radiography / 0.4 – 0.8 / 0.4 / 0.4
Cobalt-60 / Sterilization / food irradiation / 20000 / 0.4 / 0.4
Iridium-192 / Industrial radiography / 4 / 1 / 0.6
241 Am-Be / Oil well logging / 0.8 / 10
(for 241Am) / 0.001
(for 241Am)
The radioactive materials considered in this module need to be transported in activities greater than A1 and A2 values. Sothey have to be transported either in a Type B(U) / (M) packaging, which are designed to withstand accident conditions of transport.
Type B(U) and Type C packages are subject to unilateral approval and Type B(M) packages require multilateral approval.
Unilateral approval is issued only by the competent authority of the country of origin of the design of the package. Multilateral approval needs to be issued not only by the competent authority of the country of origin of the package but also by those of the countries through or into which the package is to be transported.
The consignor should procure an appropriate package which has a valid competent authority package design approval certificate. This certificate should be valid until the completion of the shipment.
Special arrangement
If conformance with all applicable provisions of the Regulations is not practicable, the consignment can be transported but only under special arrangement. Approval for transport under special arrangement must be obtained from the concerned competent authority(ies).
Obtaining necessary approvals from the competent authority
The approval requirements for the sources discussed in this module are two-fold: Design approval and shipment approval. Design approval applies to sources (special form radioactive material) and packages. Shipment approval applies to the carriage of certain packages.
The consignor should ensure the following:–
a)The package is of approved design
b)Where multilateral approval is required, it is obtained from the concerned competent authorities.
c)The package design approval certificate would remain valid until the completion of the shipment
d)If the radioactive material is declared as a special form radioactive material the design approval certificate of the radioactive material would be valid until completion of the shipment.
Approval of Special Form Radioactive Material
The design for special form radioactive material requires unilateral approval.
Approval of package design
The design of a Type B(U) package requires unilateral approval.
Each Type B(M) package design would require multilateral approval.
Approval of Shipments
Multilateral approval is required for the shipment of a Type B(M) package if :
a)its design does not take into account temperatures ranging from – 40 °C to + 70 °C for the components of the packaging
b)it is designed to allow controlled intermittent venting or
c)the activity of the radioactive material exceeds 3000A1 or 3000A2, as appropriate, or 1000 TBq, whichever is the lower.
An application for shipment approval should include:
a)the period of time, related to the shipment, for which the approval is sought;
b)the actual radioactive contents, the expected modes of transport, the type of conveyance and the probable or proposed route; and
c)the details of how the precautions and administrative or operational controls, referred to in the package design approval certificates are to be put into effect.
Approval of package design and shipment approval may be combined into a single certificate.
Approval of Shipments under Special Arrangement
If a 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
A Type B(U)/B(M) package should not contain
a)activities greater than the limit specified in the package approval certificate issued by the competent authority.
b)radionuclides different from those authorized for the package design
c)contents in a form, or a physical or chemical state different from those authorized for the package design.
Control of radiation level
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. However, in the case of a finned package, the measurement may be made at 1 m distance from the external envelope of the package.
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.Multiply it by 100. The resulting number is the transport index of the package / overpack. In the case of freight containers this value should bemultiplied by the factor given in the table below appropriate to the size of the freight container.
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.The TI of such an overpack or container may be taken as either the sum of the TIs of all the packages contained, or by direct measurement of radiation level. Similarly for any hold, compartment or the defined deck area of vessels the TI may be taken as either the sum of the TIs of all the packages stowed or the number obtained 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