GB 12711-1991 Safety standard for packaging of low and intermediate level radioactive solid waste
Some standard content:
National Standard of the People's Republic of China
Safety Standard for Low and Intermediate-Level Solid Radioactive Waste Packages
Standard of safety for low and intermediate-level solid radioactive waste packages1Subject content and scope of application
GB 12711—91
This standard specifies the design and manufacturing requirements for the safety of low and intermediate-level solid radioactive waste packages; radioactivity limits and surface contamination limits; marking and labeling, and storage and handling operation requirements. This standard applies to the packaging of low and intermediate-level solid radioactive waste generated by various nuclear facilities, nuclear research institutes, and isotope production and application units.
This standard does not apply to the packaging of radioactive tailings and waste radiation sources. 2 Reference standards
GB8703 Radiation protection regulations
GB11806 Regulations on safe transportation of radioactive materials GB11928 Temporary storage regulations for low- and intermediate-level radioactive solid wastes GB9133 Classification standards for radioactive wastes
3 Terms
3.1 Low- and intermediate-level radioactive solid wastes
Low- and intermediate-level radioactivity generated during the operation of radioactive materials is classified according to GB9133 soft solid wastes (such as waste paper, labor protection products, etc.), hard solid wastes (such as contaminated equipment parts, etc.) and low- and intermediate-level radioactive wastes that have been solidified or fixed. 3.2 Waste packaging
The sum of the waste body and its packaging container. The outer packaging is also part of the waste packaging. 3.3 Packaging container
Container for radioactive waste that has been solidified, fixed or otherwise treated. 3.4 Waste fixation
Treat the waste into a fixed form so that the radioactive nuclides are not easy to disperse and migrate during storage, transportation and disposal. 3.5 Waste liquid solidification
Convert radioactive waste liquid into or contain it in a dense solid (such as adding cement, asphalt or plastic, etc.). 3.6 Temporary storagewww.bzxz.net
Waste is temporarily stored in a storage facility and retrieved within a time limit. 3.7 Disposal
Place the waste in a place that meets the requirements for safe isolation from the biosphere and no longer retrieve it. 3.8 Multiple barriers
Approved by the State Administration of Technical Supervision on January 28, 1991 160
Implementation on December 1, 1991
GB 12711-91
A system that uses two or more independent barriers to safely isolate waste from the biosphere. The barrier includes waste bodies, packaging containers, other engineering barriers and geological media, etc.
3.9 Type A packaging
Specially designed to meet the general design and certain specific conditions, approved by the competent authorities, and the radioactivity of the waste contained does not exceed Ai or A2 values (see GB11806 for waste packaging). 3.10 Type B packaging
Specially designed to meet the general design and certain specific conditions, approved by the competent authorities, and the radioactivity of the waste contained exceeds A or A2 values.
3.11 High integrity container
A specially designed and manufactured container with high strength, sealing, chemical stability and thermal stability, which can be used to load radioactive waste that has not been solidified or fixed, such as evaporated boron-containing waste liquid, drained waste resin, burnt ash, etc. 3.12 Outer packaging
When the surface dose equivalent rate of the waste packaging exceeds the management limit, the packaging is attached to the outside of the waste packaging to reduce the radiation level. 3.13 Alpha waste
Waste contains one or more nuclides emitting alpha rays (atomic number 92), and its specific activity is higher than the limit specified by the state. 3.14 Non-fixed surface contamination
refers to contamination that can be removed from the surface by conventional wiping methods. 4 General principles
4.1 Any unit that produces low- and medium-level radioactive solid waste must have measures to safely, reliably and economically package radioactive waste to prevent radioactive materials from being released into the environment in unacceptable quantities, ensure that the radiation received by the public and occupational personnel does not exceed the dose equivalent limit, and reaches the lowest level that can be reasonably achieved. 4.2 Waste packaging must meet the requirements of transportation, storage and disposal, facilitate operation and handling, ensure that it can be retrieved during the storage period, and can serve as a barrier in the multi-barrier system in the early stage of disposal, playing a role in safe isolation from the biosphere. 4.3 Waste should be treated by volume reduction (such as incineration, compression, etc.) and containers with high volume utilization efficiency should be selected to reduce the burden of waste storage, transportation and disposal.
4.4 Wastes should be collected and packaged in a classified manner, and different types of wastes should be packaged in different containers. Most of the low- and medium-level solid waste packaging belongs to Type A packaging, and a small part belongs to Type B packaging. 5 Basic requirements for packaging of low- and medium-level radioactive solid wastes 5.1 Radioactive wastes must be placed in packaging containers in accordance with operating procedures. 5.2 Except for the case of using specially designed and manufactured high-integrity containers, all wastes to be disposed of should be solidified, fixed or otherwise treated separately, such as evaporation residues, sedimentation slurry, Van burnt ash, waste ion exchange resin, etc., which should be solidified or fixed with cement, asphalt or plastic in advance. Compressible wastes should be compressed. After the dismantled and cut equipment parts are loaded into barrels, it is best to pour cement mortar or asphalt to fill the pores. 5.3 Wastes containing radiolysis gases should be left in a space of 10% of the volume. 5.4 Cement solidified bodies should be capped after reaching the specified curing period; asphalt solidified bodies should be capped after complete cooling; plastic solidified bodies should be capped after the polymerization reaction is completed.
5.5 Waste packaging containers are not allowed to contain
a. Explosive substances or substances that can produce explosive reactions after contact with water; b. Spontaneous combustion, flammable or volatile substances;
Untreated animal bodies;
d. Liquids or wet bodies. The weight of free liquid in the container should be less than 1% of the weight of solid waste. 161
GB 12711--91
6 Design and manufacturing requirements for packaging containers for low- and intermediate-level radioactive solid wastes 6.1 Packaging containers for low- and intermediate-level radioactive solid wastes can be metal barrels or boxes made of carbon steel or stainless steel, concrete barrels or boxes, or cast iron containers, polymer-impregnated concrete containers, fiberglass containers or high-integrity containers. 6.2 The packaging containers of low- and medium-level radioactive solid waste should be designed, manufactured and inspected according to the temporary storage period, environmental conditions of the storage site, transportation methods, disposal methods, waste properties and expected accidents, and meet the following requirements: a. Strong and sturdy, able to withstand the pressure of the stack and stack at least five layers without obvious deformation. In the event of a fall or collision during storage operation and transportation, the radiation level caused by the loss of the radioactive material inside shall not exceed 20%; b. Good sealing, the cover will not be opened due to internal pressure; the acceleration, vibration and resonance that may occur during conventional transportation will not damage the integrity of the packaging container; c. The cover should be easy and reliable to operate, and the fastening parts will not loosen; d. Anti-corrosion, anti-irradiation, anti-aging, and anti-biological erosion, and can be retrieved intact within the storage period specified in the design; e. The material and structure of the packaging container must be compatible with the physical and chemical properties of the waste body; f. The surface is smooth and flat, without water accumulation, and easy to decontaminate; the waste packaging is easy to carry with a crane or forklift, and the lifting parts will not be damaged when used in the predetermined manner; h. Reasonable material selection, simple structure, and easy manufacturing. 6.3 In order to facilitate handling and stacking operations, the packaging container should have a uniform size. Considering the diversity of low- and medium-level solid waste types, a series of standard containers should be specified for selection. 6.4 Waste packaging containers must be designed, produced and sold by licensed units. 6.5 The design, processing and manufacturing of waste packaging containers must be carried out in accordance with the specifications and undergo quality inspection. For inspection items and methods, see GB 11806.
7 Radioactivity limits for low- and medium-level radioactive solid waste packaging 7.1 Occupational personnel and the public must not be exposed to radiation exceeding the limit. The radiation level at any point on the outer surface of the package must be ≤2.0mSv/h; the radiation level at any point 1m away from the outer surface of the package must be ≤0.1mSv/h. Those exceeding the above limits must be shielded by adding outer packaging.
7.2 The content of fissile material in the waste packaging must be less than 15g. 7.3 The content of alpha waste in the waste packaging shall not exceed the national alpha waste standards. 8 Limits for surface contamination of low- and medium-level radioactive solid waste packaging Non-fixed contamination on the surface of waste packaging must be below the following limits: Natural, depleted uranium, natural β emitters 4Bq/cm2, low-toxicity α emitters 4Bq/cm2, other α emitters 0.4Bq/cm2 9 Markings and labels 9.1 Type A packaging containers are painted yellow, and Type B packaging containers are painted orange. 9.2 The outer surface of the waste packaging must have a radioactive mark and a waste packaging number. The radioactive mark is a black trefoil symbol (see Appendix A (Supplement)), which is located in the center of the upper half of the packaging container. The outer diameter of the trefoil symbol is 1/3~~1/5 of the height of the container. The packaging number is located in the center of the lower half of the packaging container. It is a black Arabic numeral with a height of 1/7~1/10 of the height of the container. This mark and number must be eye-catching, clear, water-resistant and can be preserved for a long time. 9.3 The waste packaging label should clearly fill in the following contents: a. Waste category; b. Main radioactive nuclides and specific activity; c. Surface dose rate and dose rate at 1m away; d. Total weight; waste generating unit, date and number. GB 12711-91 9.4 The content on the label must be consistent with the registration content, and should be checked and verified during storage and consignment. Records and their copies should be properly preserved to prevent deterioration, damage and loss.
10 Stacking, handling and rolling operations
10.1 Stacking and transportation loading and unloading operations must be performed by qualified personnel or under the supervision of qualified personnel. 10.2 Appropriate loading and unloading equipment and tools should be used for loading and unloading operations without failure and overload to ensure safety and quality of loading and unloading. 10.3 Waste packaging should be stacked neatly, not too high or too wide, to prevent falling and magnetism. 10.4 Operators and the public dose limit shall comply with GB8703. 1G.5 Personnel who operate waste packaging should wear personal dosimeters and receive radiation monitoring. 10.6 The storage of waste packaging must comply with the provisions of GB11928. 10.7 The transportation of waste packaging must comply with the provisions of GB11806. 11 Emergency planning and preparation
11.1 Units that package, transport and store waste should have emergency preparations. In the event of an accident, the on-site personnel must take emergency measures to prevent the radioactive contamination from expanding and immediately report to the leaders of the unit and the competent department. 11.2 If the waste packaging is found to be damaged and radioactive materials are lost, or if damage and radioactive materials are suspected to have occurred, personnel without appropriate protective measures must be prohibited from approaching the waste packaging, and the scope and level of contamination must be checked by radiation protection personnel as soon as possible. When it is found that contamination has occurred, the area must be immediately demarcated and marked, and decontamination treatment must be carried out as soon as possible. When the human body is contaminated or irradiated, human body decontamination must be carried out under the guidance of safety protection and medical and health personnel, the exposure dose must be estimated, and medical treatment suggestions must be made as needed. 11.3 Damaged waste packaging must be promptly covered with a container outside the original container. 11.4 Waste storage places must have waterproof, fireproof, lightning protection, and earthquake-resistant measures. In the event of fire, water, ground and other incidents, emergency measures must be taken to prevent endangerment of radioactive waste packaging. 11.5 Loss and theft must be prevented during transportation and storage. In case of loss or theft of waste packaging, relevant departments must be reported as soon as possible and all necessary information must be provided so that the lost or stolen waste packaging can be recovered in time. 12 Quality Assurance
12.1 Quality assurance outlines and measures must be formulated for the design, manufacture, inspection of waste packaging containers, and the storage and handling operations of waste packaging to ensure compliance with the relevant provisions of this standard. 12.2 Relevant departments and personnel must be held accountable for all violations. 163
Additional Notes:
GB12711—91
Appendix A
Radioactive Sign
(Supplement)
Three-leaf symbol (its proportional relationship is based on the central circle with radius R) Figure Al
This standard was proposed by China National Nuclear Corporation. This standard was drafted by China Institute of Atomic Energy. The main drafters of this standard are Luo Shanggeng, Zhang Chuanzhi, Shao Fuyi, and Wang Lian. 164
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