核与辐射应急照射情况下公众照射的防护

2007年ICRP第103号出版物出版后,IAEA据此修订了安全丛书115号,形成了IAEA新的《辐射防护与辐射源安全:国际基本安全标准》(GSR-3,2014)。其中关于核与辐射应急照射情况下公众照射的防护,与115号报告有了较大的变动,本文对这些差异进行了分析,并对新标准在应用中应加以关注的相关问题进行了讨论。     

The First 40 FT Freight Container in Europe Qualified as an IP-2/IP-3 and Type a Package

Abstract

The first successful free fall drop test with a 40 ft ISO freight container in Europe (as far as we know also in the world) took place in Bremen (Germany) at the dry dock of the former Vulkan ship yard on 25 September 1998. This drop test was performed to qualify the ISO Boxcontainer as an IP-2/IP-3 and Type A package in accordance with IAEA Regulations Safety Series No 6 (1985 edition, as amended 1990) and the new IAEA Safety Standards Series No ST-1 (1996 Edition). The freight container has successfully passed the whole sequence of required tests to demonstrate compliance with Type A requirements (free drop test, stacking test, penetration test and, instead of the water spray test, the more stringent pressure and bubble test was performed) of the IAEA Regulations. This paper concentrates on the free fall drop test because this is the most difficult of the required Type A tests which needs to be passed. Further, the free fall drop test is required to qualify a freight container in accordance with the alternative requirements for industrial packages IP-2,3 (new ST-1, § 627), the requirements for industrial packages (new and old IAEA Regulations) and Type A requirements. Therefore, the freight container was qualified as IP-2,3 and Type A package performing a free fall drop test. The overall dimensions of the so called LONGFORCE® container are: length 12192 mm (40 ft); width 2438 mm (8 ft); height 2491 mm (8 ft 6 in). The 40 ft ISO freight container prototype was fully loaded with 28 t of steel plates together with shock absorbing material to simulate the load and load securing system. The total drop test weight was 35·6 t. In accordance with IAEA Regulations Safety Series No 6 and ST-1, the LONGFORCE® container was dropped onto an unyielding foundation in a position which suffered the maximum damage in respect of the package safety features. The package was dropped on its corner, door side down on the roof, with the centre of gravity over the impact area (slap-down drop). The container was lifted 12·6 m high (highest point) respectively 0·3 m (lowest point) under a drop angle of 70°. The combined mass of the concrete block and the steel plate (impact pad) was way above 100 times that of the container test specimen. The first impact resulted in an acceleration of about 100 g where the maximum was near the impact. The second impact, in general, yielded far higher acceleration values in the vertical direction of 160 up to 200 g. A third impact was recorded which turned out to be decisive, showing maximum acceleration readings in the range of about 200 up to 250 g. The container was inspected after the drop test and deformations of the container rear corner castings (area second impact) and a small weld crack in one of the corner castings welds was found. On the container floor one third of transverse support beams showed Sform distortion. The LONGFORCE container was leak tested prior to and after the drop test in compliance with the STM (STM stands for Safety Technology Management GmbH, owner of the container design and rights and sponsor of the drop test work) leak test procedure. The leak tests consisted of filling the container with pressurised air up to 5 kPa and recording a possible pressure drop over a determined test period. The container was considered leak tight prior to and after the drop test based on the permissible limits set in the leak test procedure. The free fall drop test is considered a full success qualifying the 40 ft LONGFORCE container as an IP-2/IP-3 Type A package in compliance with the IAEA SS No 6 and also with the new IAEA ST-1 regulations.     

Test Facilities for Radioactive Materials Transport Packages (BEBIG GmbH,Germany)

Abstract

BEBIG GmbH, located in Berlin, Germany, offers full capabilities for the testing of Type A packages according to IAEA regulations. This paper describes the facilities available.     

Qualifying a 40 ft ISO Freight Container as a Type IP-2, IP-3 Package by Performing a Full Scale Drop Test

Abstract

The first successful worldwide free fall drop test with a 40 ft ISO freight container took place in Bremen (Germany) at the dry dock of the former Vulkan shipyard on 25 September 1998. This drop test had to be performed to qualify the ISO Boxcontainer as a Type IP-2, IP-3 package in accordance with the new IAEA Safety Standards Series No ST-1 (1996 Edition). Dynamic impact requirements will become mandatory for freight containers to be qualified as Type IP-2,3 packages in compliance with IAEA ST-1 paragraph §627 ‘Alternative Requirements for IP-2,3 Packages’ (comes into force in January 2001). STM has fulfilled the dynamic impact requirements in performing a full scale drop test. The 40 ft ISO freight container prototype (L × W × H = 12192mm × 2438 mm × 2491 mm) was fully loaded with 28 t of steel plates together with shock absorbing material to simulate the load and load securing system. The total drop test weight was 35.6 t. In accordance with the new IAEA Safety Standards Series No ST-1 requirements, the so-called LONGFORCE® container was dropped onto an unyielding foundation in a position which produced the maximum damage in respect of the package safety features. The package was dropped on its comer, door side down on the roof, with the centre of gravity over the impact area (slap-down drop). The container was lifted 12.6 m high (highest point) and 0.3 m (lowest point) under a drop angle of 70°. The combined mass of the concrete block and the steel plate was more than 100 times that of the container test specimen. The first impact resulted in an acceleration of about loog where the maximum was just before the impact. The second impact, however, turned out to be decisive showing maximum acceleration readings in the range of 250g. The container has been inspected after the drop test and deformations of the container rear comer castings (area of second impact) and a small weld crack in one of the comer casting welds was found. On the container floor one third of transverse profiles showed S-form distortion. The LONGFORCE container was leak tested prior to and after the drop test in compliance with the STM leak test procedure. The leak tests consisted of filling the container with pressurised air up to 5 kPa and recording a possible pressure drop over a determined test period. The container was considered leak tight prior to and after the drop test based on the permissible limits set in the leak lest procedure. The free fall drop test is considered a full success qualifying the 40 ft LONGFORCE container as Type IP-2, Ip-3 package in compliance with the new IAEA Safety Standards Series No ST-1 requirements.     

The relevance of IAEA tests to severe accidents in nuclear fuel cycle transport

Abstract

The design and performance standards for packages used for the transport of nuclear fuel cycle materials are defined in the IAEA Regulations for the Safe Transport of Radioactive Materials, TS-R-1, in order to ensure safety under both normal and accident conditions of transport. The underlying philosophy is that safety is vested principally in the package and the design and performance criteria are related to the potential hazard. Type B packages are high-duty packages which are used for the transport of the more radioactive materials, notably spent fuel and vitrified high-level waste (VHLW). Tests are specified in the IAEA regulations to ensure the integrity of these packages in potential transport accidents involving impacts, fires or immersion in water. The mechanical tests for Type B packages include drop tests onto an unyielding surface without giving rise to a significant release of radioactivity. The objects which could impact upon a package in real-life transport accidents, such as concrete roads, bridge abutments and piers, will yield to some extent and absorb some of the energy of the moving package. Impact tests onto an unyielding surface are therefore relevant to impacts onto real-life objects at much higher speeds. The thermal test specifies that Type B packages must be able to withstand a fully engulfing fire of 800°C for 30 min without significant release of radioactivity, and this has to be demonstrated, for example, by analytical studies backed up by experimental tests. The regulations also specify immersion tests for Type B packages of 15 m for 8 h without significant release of radioactivity; and in addition for spent fuel and VHLW packages, 200 m for 1 h without rupture of the containment. There is a large body of evidence to show that the current IAEA Type B test requirements are severe and cover all the situations which can be realistically envisaged in the transport of spent fuel, VHLW and other fuel cycle materials. Any proposals for more severe tests, which have little technical justification, should therefore be treated with caution since this could result in a loss of public confidence in the current regulations, and the ratcheting up of design requirements which could not be justified on quantitative safety grounds.     

Movements of radioactive material on nuclear licensed sites

Abstract

The regulations governing the transport of radioactive materials are prepared by the International Atomic Energy Agency (IAEA) and then introduced into modal regulations and national legislation. These regulations are based on a graded approach to contents limits for packages and conveyances and to performance standards applied to package designs depending upon the hazard of the radioactive contents.

They apply to the transport of radioactive material in the public domain in which the packages can be conveyed by road, rail, sea, inland waterways or air transport modes and may share transport routes with movements of people and cargoes in close proximity.

In contrast, the movement of radioactive materials on nuclear sites is a much more controlled operation. Normally, only road or rail transport is involved, there are much lower volumes of other traffic and any hazards during the movement are generally less severe than the test conditions in the IAEA transport regulations representing accident conditions of transport.

Furthermore, there is no internationally accepted set of design standards applicable to packages intended purely for onsite movements.

In the UK, suitable safety cases need to be prepared to demonstrate the acceptability of the onsite movement of radioactive material to the regulator, the Nuclear Installations Inspectorate (NII). The safety case includes engineering substantiation against appropriate design standards. However, the criteria in the design standards do not need to be as demanding as those in the IAEA transport regulations because of the controlled environment within which onsite movements take place.

The principles of the graded approach in the IAEA transport regulations can be applied to onsite movements of radioactive material. However, the high level of safety resulting from compliance with these regulations can be achieved for movements of radioactive material packages on a nuclear licensed site by amending limits and test criteria to take account of the stringent onsite controls and environment. Examples of this are increasing the package contents limits for a particular package type, reducing the package test requirements or a combination of the two.

There are also general requirements in the IAEA transport regulations for all packagings and packages, and aspects of these can be applicable for packages used for onsite movements of radioactive material. However, there are aspects of these where the detailed implementation can be relaxed for onsite movements, such as the acceleration values experienced at the typically low speeds of onsite movements and the limited ambient temperature and pressure ranges for a specific site.

The present paper discusses various differences between transport of radioactive material in the public domain and on nuclear licensed sites.     

放射性物质运输货包试验工作进展

运输货包的固有安全性是放射性物质运输安全的前提,货包要经受多种条件的试验验证,国际原子能机构的《放射性物质安全运输规程》规定了放射性物质运输货包要经受的正常和事故运输条件下的试验要求。本文简要介绍了货包试验的主要内容及国内外货包试验验证工作的进展状况,建议加强国内的放射性物质运输货包试验验证工作,保证我国放射性物质的运输安全。     

欧洲联盟委员会关于制定保护公众和工作人员健康免受电离辐射危险的基本标准的指令

本文简要介绍了国际原子能机构等国际组织于１９９４年联合颁布的“国际电离辐射防护和辐射源安全基本安全标准”的主要方面，介绍了欧洲联盟委员会１９９６年初通过的关于制定保护公众和工作人员健康免受电离辐射照射危险的基本标准的指令的主要内容。该指令包括５７个条款，分属１０个部分和３个附件，分别涉及：ＩＣＲＰ和ＩＣＲＵ的新建议及一些辐射防护术语定义的改进；指令的适用范围；申报和审批相关实践的体系；辐射防护体系的一般原则；有效剂量的估算；工作人员的运行防护；导致过高剂量天然辐射照射的职业性活动；正常情况下公众辐射防护的实施；干预；达到该指令要求的时间期限。该指令中采用的剂量限值为ＩＣＲＰ６０号出版物中所建议的     

New Basic Safety Regulations for Radioactive Material Transport in Russia

Abstract

In this paper the system of standards regulating the transport of radioactive material in Russia, the basic principles and provisions of the new Russian regulations and some deviations from IAEA rules and regulations are briefly considered. The problems connected with putting into force the new transport regulations, including problems with the use of packages designed and manufactured prior to these regulations, are also considered.     

Revised guidelines for the procedure for approval of package designs in Germany

Abstract

The IAEA Regulations for the Safe Transport of Radioactive Material TS-R-1 are applied in Germany through the implementation of the Dangerous Goods Transport Regulations for Class 7 of the International Modal Organisations (ADR, RID, IMDG-Code, ICAO-TI). Based on this the procedures for the approval of package designs used in Germany are in compliance with the provisions of TS-R-1. BfS is the competent authority for the approval of Type B(U), Type B(M) and Type C packages and all packages containing fissile material, and BAM is the competent authority for approval of H(U)/H(M) packages for UF6, special form and low-dispersible radioactive material. The basis for the procedure for approval of package design in Germany are the R 003 guidelines, first issued by the Ministry of Transport, Building and Housing (BMVBW) in 1991. These guidelines have been reviewed and revised to reflect the latest developments in the regulations as well as in regulatory practice. In particular they have been extended to the procedures for approval of Type C packages and packages subject to transitional arrangements, special form and low-dispersible radioactive material, and provide more detailed information to the applicant about the requested documentation. This paper gives an overview of the main parts and provisions of the revised R 003 guidelines issued in December 2004 including scope, responsibilities, application, documentation, evaluation and certification for the various approval procedures.     

Safety considerations during transport of radioactive material

Abstract

The International Atomic Energy Agency (IAEA) regulations establish requirements that must be satisfied to ensure safety and to protect people, property and the environment from the effects of ionisation radiation during the transport of radioactive material (RAM). The package types A and B most frequently used for the transport of RAM in Romania are subjected to various qualification tests in accordance with the National Regulations and IAEA recommendations; these tests are carried out by the Reliability and Testing Laboratory of the Institute for Nuclear Research, Pitesti. These tests include the evaluation of non-fixed contamination, as is described in the present paper. Regulatory requirements related to contamination for packages used for transport and storage of RAM and the method used to monitor the evaluation of the surface contamination of packages are also presented. These test requirements are performed under a strict quality assurance programme based on specific procedures given prior approval by the Romanian Nuclear Regulatory Body (National Commission for Nuclear Activities Control).     

Implementation of the IAEA's Radioactive Material Transport Regulations

Abstract

In its seventh meeting in 1989 the Standing Advisory Group on the Safe Transport of Radioactive Material (SAGSTRAM) recommended that all Member States adopt the 1985 Edition of the IAEA Regulations for the Safe Transport of Radioactive Material, Safety Series No 6, by I January 1991. In order to determine the extent to which that recommendation was fulfilled, a questionnaire on the implementation of Radioactive Material Transport Regulations was developed by the IAEA and sent to all Member States. The main results are that 59 of the 64 responding Member States have regulations for both domestic and international shipments of radioactive material, and that all regulations are based primarily on Safety Series No 6. For domestic and international shipments of radioactive material, 51 (86%) and 54 (92%) of the Member States with regulations, respectively, use the 1985 Edition of Safety Series No 6 (original, as supplemented or amended) as the primary basis for national regulations. These results show that Safety Series No 6 is widely used by the Member States as the basis of their national regulations and the 1985 Edition has been quickly implemented into their regulations.     

The Planned Integrated Transport System for the Deep Repository in the UK

Abstract

UK Nirex Ltd is responsible for developing a deep repository for the safe disposal of intermediate and low level radioactive wastes (ILW and LLW), and is concentrating its investigations on Sellafield as a potential location. A key part of the repository development programme is a transport system to deliver packaged wastes from sites elsewhere in the UK. The transport system must be able to handle a range of standard waste packages, and all transport through the public domain must comply with the IAEA Transport Regulations. Two design concepts have been developed for re-usable shielded transport containers for ILW, which are predicted to withstand accidents at least as severe as the IAEA Type B test conditions. Assessment, testing and further development of both concepts continues, with a view to selecting one for quantity production. Nirex is working closely with various organisations to establish the optimum transport routes for a potential repository at Sellafield. The current policy is that rail transport shall be used wherever practical for the transport of waste to the repository, although some road transport may also be required; the company has assessed a range of options. A Probabilistic Safety Assessment of the proposed transport operations has predicted that the radiological risks are expected to be extremely low, reflecting the adequacy of the packaging concepts. In addition, Nirex has identified a suitable transport emergency plan to deal with any unforeseen events.     

Excluded,exempt and LSA quantities for transport of NORM radioactive material

Abstract

The main objectives of this research work are the determination of the quantities of naturally occurring radioactive material (NORM) that can be excepted from the International Atomic Energy Agency (IAEA) Transport Regulations, the establishment of quantities of NORM that can be transported in excepted packages as well as the provision of sound basis for the establishment of limiting values for the classification of NORM as low specific activity material I raw for transport purposes, in order to compare with the actual transport limits established in the IAEA Transport Regulations for this type of material.     

Sea Transport of Radioactive Materials in Egypt

Abstract

In Egypt the national regulations for safe transport of radioactive materials (RAM) are based on the International Atomic Energy Agency (IAEA) regulations. In addition, regulations for the safe transport of these materials through the Suez Canal (SC) were laid down by the Egyptian Atomic Energy Authority (EAEA) and the Suez Canal Authority (SCA). They are continuously updated to meet the increased knowledge and the experience gained. The technical and protective measures taken during transport of RAM through SC are mentioned. Assessment of the impact of transporting radioactive materials through the Suez Canal using the INTERTRAN computer code was carried out in cooperation with IAEA. The transported activities and empty containers, the number of vessels carrying RAM through the Canal from 1963 to 1996 and their nationalities are also discussed. The protective measures are mentioned.     

The Status of IAEA TECDOC 717 and Further Efforts to Reach Consensus

Abstract

In August 1993 IAEA published TECDOC-717 entitled Guidelines for Safe Design of Shipping Packages Against Brittle Fracture which also takes the form of a draft Appendix to Safety Series No 37. It was recognised that the views expressed did not necessarily reflect the views of governments of all Member States and an opportunity was given to all Member States to comment before an independent expert was asked to produce a revised draft taking into account comments received and his own technical views. The paper presents a summary of the proposed changes to move the TECDOC forward to the status of Appendix IX of Safety Series No 37 and discusses the key issues involved in designing packages against brittle fracture failure. The responses received from Member States and the position reached at the meeting of the Revision Panel in October 1994 are described and a possible way forward to resolve remaining difficulties is presented.     

Scale model impact limiter in type assessment of radioactive material transport packages

Abstract

In Germany, the Federal Institute for Materials Research and Testing (BAM) is the competent authority for the mechanical and thermal design safety assessment of transport packages for radioactive material according to IAEA regulations. The combination of experimental and numerical safety proof forms the basis for a state of the art evaluation concept. Reduced scale models are often used in experimental investigation for design assessment of transport packages corresponding to IAEA regulations. This approach is limited by the fact that a reduced scale model cask can show different behaviours from a full scale cask. The paper focuses on the peculiarities of wood filled impact limiter of reduced scale models. General comments on drop testing with reduced scale models are given, and the relevant paragraphs of the IAEA regulations and Advisory Material are analysed. Possible factors likely to influence the energy absorbing capacity of wood filled impact limiting devices are identified on the basis of similarity mechanics. Among possible significant influence factors on the applicability of small scale models are strain rate and size effects, failure mechanisms, underground compliance, gravitational and friction effects. While it was possible to derive quantitative estimations for the influence of strain rate, size effects and target compliance, it was not possible to evaluate the influence of compression mechanisms and gravitation. In general, if reduced scale models are used in proof of safety, uncertainties increase in comparison with full scale models. Additional safety factors to exclusively cover the uncertainties of reduced scale model testing have to be demanded. The possible application of reduced scale models in regard to crucial aspects for proof of safety has to be analysed critically.     

Study of the Accident Environment During Sea Transport of Nuclear Material: Analysis of An Engine-Room Fire on a Purpose-Built Ship

Abstract

The programme goal was to show that the IAEA safe transport regulations adequately cover the thermal effects of an engine-room fire on plutonium transport packages stowed aboard a purpose-built ship. The packages are stored in transport containers located in a cargo hold of the ship. For this study, it was assumed that the packages in No 5 Hold, adjacent to an engine-room, could be subject to heating due to a fire in the engine-room. The No 5 hold and the engine-room are separated by a water-filled bulkhead. This study addressed the heat transfer from an engine-room fire that could heat and evaporate water out of the water-filled bulkhead and the resulting temperature conditions around the packages and inside the packages near their elastomeric seals.     

Test Facilities for Radioactive Material Transport Packages (Ontario Hydro,Canada)

Abstract

The Ontario Hydro test facilities for Type A and Type B packages for the transport of radioactive materials are described.     

Test Facilities for Radioactive Material Transport Packages (AEA Technology,Winfrith, UK)

Abstract

Transport packages for radioactive materials are tested to demonstrate compliance with national and international regulations. The involvement of AEA Technology is traced from the establishment of the early IAEA Regulations. Transport package design, testing, assessment and approval requires a wide variety of skills and facilities. The comprehensive capability of AEA Technology in these areas is described with references to practical experience in the form of a short bibliography. The facilities described include drop-test cranes and targets (up to 700te); air guns for impacts up to sonic velocities; pool fires, furnaces and rigs for thermal tests including heat dissipation on prototype flasks; shielding facilities and instruments; criticality simulations and leak test instruments. These are illustrated with photographs demonstrating the comprehensive nature of package testing services supplied to customers.