Conformity assessment—Specification for biological quality control materials without metrological traceabilit
Some standard content:
ICS 03.120.20
National Standard of the People's Republic of China
GB/T27424—2020
Conformity Assessment
Non-traceable biomass control products
Quality Control Specification
Conformity assessment-Specification for biological quality control materials without metrological traceability2020-11-19 Released
State Administration for Market Regulation
National Standardization Administration Committee
Released
2021-06-01Implementation
GB/T27424—2020
Foreword
Introduction
Scope
Normative reference documents
Terms and Definition
General Provisions
Development
Acceptance
Transportation
Storage
Use
Disposal
Documentation and identification managementbZxz.net
Appendix A (informative appendix)
Appendix B (informative appendix)
Appendix C (informative appendix)
References||tt| |Quality control example of morphological standard quality control product
Quality control method for uniformity and stability assessment of herpes simplex virus type II IgG antibody quality control example rKaeerKAca-
Foreword||tt| |This standard is drafted in accordance with the rules given in GB/T1.1-2009. This standard is proposed and coordinated by the National Certification and Accreditation Standardization Technical Committee (SAC/TC261). GB/T27424—2020
This standard was drafted by: Qingdao Customs Technology Center, China National Accreditation Center for Conformity Assessment, China Institute of Metrology, Beijing Aerospace General Hospital, Fuzhou Customs Technology Center, Dalian Customs Technology Center, Rizhao Customs Comprehensive Technical Service Center, China Animal Health and Epidemiology Center, Zhengzhou Antu Bioengineering Co., Ltd., Shengyuan Nutritional Food Co., Ltd., Shandong Animal Disease Prevention and Control Center. The main drafters of this standard: Lei Zhiwen, Liu Peihai, Lu Jing, Wang Pin, Chen Baorong, Fu Boqiang, Liu Gongcheng, Zheng Teng, Wang Youfu, Jiang Yong, Li Yang, Lan Zouran, Tao Yufeng.
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GB/T27424—2020
Introduction
In biological measurement, it is often encountered that there is no suitable reference material, which is developed in the laboratory or obtained from Externally obtained quality controls are used to evaluate the precision of biological measurement results to meet the specific quality control requirements of laboratory management. Common non-traceable biomass control products are divided into antigens, antibodies, virus strains, strains, cells, etc. according to their material attributes. This standard does not intend to define a new category of standard materials/standard samples. The "non-traceable biomass control substances" in this standard are quality control substances used in the biological field. "Non-traceable" is the characteristic of this type of substance, and "biology" is the field of its application. Non-traceable biological quality control products belong to a class of practical reference materials/standard samples used for quality control. They cannot be traced or do not need to establish traceability according to the application purpose. The determination results are not required to have metrological traceability and measurement uncertainty. , but its homogeneity, stability and other properties should meet the expected specific application requirements, and some biomass control products have biosafety risks, so quality control should be carried out throughout the "life cycle" of non-traceable biomass control products .
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1 scope
Conformity assessment non-traceable biomass control products
Quality control specifications
GB/T27424 —2020
This standard specifies the quality control requirements for the entire "life cycle" of non-traceable biomass control products, including development, acceptance, transportation, storage, use and disposal, as well as document preparation and labeling management during the quality control process Requirements, this standard is applicable to the quality control of non-traceable biological quality control products in laboratory biological testing activities. The quality control of other non-traceable quality control products or reference materials can also be used as a reference. Normative References
The following documents are essential for the application of this document. For dated references, only the dated version applies to this document. For undated referenced documents, the latest version (including all amendments) applies to this document. GB/T15000.2-2019: Working Guidelines for Standard Samples Part 2: Common Terms and Definitions GB/T15000.3 Working Guidelines for Standard Samples (3) General Principles and Statistical Methods for Valuation of Standard Samples GB/T20468 Clinical Laboratory Guidelines for Indoor Quality Control of Quantitative Measurements GB/T21415-2008 Metrology Traceability of Calibrators and Control Substances for Quantitative Measurement of Biological Samples in In vitro Diagnostic Medical Devices WS/T356 Guidelines for Matrix Effects and Interoperability Assessment Terms and Definitions
The following terms and definitions as defined in GB/T21415-2008 and GB/T15000.2-2019 apply to this document. For ease of use, some terms and definitions in GB/T21415-2008 and GB/T15000.2-2019 are repeated below. 3.1
quality control materials quality control materials
standard materials used for quality control in the measurement process. [GB/T15000.2--2019. Definition 2.1.223.2 | Purpose There is no need to establish traceability of the reference material 3.3
homogeneity
homogeneity
The consistency of a specified characteristic value of a specific part of the reference material. [GB/T15000.2—2019.Definition 2.1.12] 3.4
stability
stability
When a reference material is stored under specified conditions, a specific characteristic value remains stable for a specified period of time Maintain within the specified limits [GB/T15000.2-2019.Definition 2.1.151
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GB/T27424—2020
Interchangeabilitycommutability||tt ||Characteristics of standard materials. A consistent procedure between the mathematical relationship between the measurement results produced by two measurement procedures for measuring a specific amount of a given substance and the mathematical relationship produced by measuring the amount of a regular sample. Note: In some fields, interchangeability is also called interoperability. [GB/T21415-2008.Definition 3.9]
matrixeffect
Matrix effect
In addition to the measured characteristics, the sample characteristics have a specific measurement procedure to determine the measured characteristics and their measured values. Effect Note 1: The clear cause of a certain matrix effect is an effect quantity Note 2: "Matrix effect" is sometimes incorrectly used to describe the lack of analyte due to denaturation of the analyte or the addition of non-real components (surrogates) to simulate the analyte, etc. Interchangeability, Note 3: "Matrix effect" is sometimes also called "matrix effect". [GB/T21415—2008, definition 3.15]
fixed valueassignment
The measurement of characteristic values ??or characteristic attributes of reference materials is part of the development (production) process [GB/T15000.2—2019, Definition 2.1.10]4 General
Non-traceable biological quality control products belong to a class of practical reference materials/standard samples used for quality control. They cannot or do not need to establish tide origin and do not require fixed value results. It has metrological tide origin and measurement uncertainty, and some of them have biosafety risks. The laboratory should identify the quality control elements of non-traceable biomass control products, establish quality control procedures, carry out quality control, and record them 5 Development
5.1 Raw material selection and collection
5.1.1 Non-traceable The raw materials required for the development of traceable biomass control products include biological raw materials, excipients, chemical raw materials and other auxiliary materials. The quality of various raw materials and excipients should comply with regulations, standards and experimental requirements. If raw materials and excipients are supplied from outside, the laboratory should evaluate the supplier's qualifications, capabilities and performance, and retain the procurement contract, quality standards, factory inspection reports and the laboratory's technical acceptance data, etc. 5.1.2 When collecting raw materials required for the development of non-traceable biomass control products, the following specific matters should be considered: a) When raw materials are collected from human or animal tissues and organs, pathogenic microorganisms or genetically engineered materials, all activities should comply with national laws, regulations and safety requirements and ethical requirements;
b)
The authenticity of the selected samples has a high degree of confidence and avoids the use of wrong biological tissues: c
Regarding the preservation and use of patient samples Ethics; d) Before collecting raw materials (such as serum, pathogenic microorganisms), the type and dosage of the inactivator should be determined, and the potential risks of the relevant inactivators should be assessed (including the potency of the raw materials and the impact on humans); Biosafety risks of the processing methods of collected raw materials, such as when there may be contact with contaminated sharp objects or aerosols are easily generated during the preparation process,
5.1.3 To avoid any contamination, respond Raw materials and excipients used in the development of non-traceable biomass control products should be labeled, properly stored and isolated to prevent misuse, damage, deterioration or contamination. There should be safety measures for the storage of toxic and hazardous raw materials. 5.2 Raw material processing and handling
5.2.1 After collecting all necessary raw materials and auxiliary materials, they should be processed and handled appropriately. Processing and treatment sites, facilities and equipment, personnel protection, waste disposal, etc. should meet the corresponding level of safety protection requirements. 5.2.2 Raw material processing and treatment processes, including but not limited to : a) Drying or freeze-drying;
b) Grinding and crushing;
Sieving or extraction;
Mixing and blending;
e)
Filtration or purification;
f)
Sterilization or inactivation;
g) Stabilization;
h) Bioengineering methods.
GB/T27424—2020
5.2.3 Certain processing and treatment techniques may affect the uniformity of non-traceable biomass control products. For example, freeze-dried samples may have different drying degrees. Through program design and process optimization, we should try to avoid or reduce its impact, avoid pollution, and prevent changes in characteristic values. 5.3 Packaging and packaging | , evaluate matrix effect in accordance with WS/T356. Note: For example, when preparing serum quality control products. When using artificial matrix or animal serum to dilute positive (or high-value) serum, evaluate the matrix effect. 5.3.2 During the aliquoting process of batch samples, aliquots should be avoided or reduced as much as possible. Effect of method on sample uniformity. Special environmental requirements such as biosafety, cleanliness and temperature should be met during packaging. It can be packaged in a clean room, ultra-clean workbench (HEPA filter) or biosafety cabinet. 5.3.3 The packaging should meet the intended use of the non-traceable biomass control product and comply with the requirements for the transportation and use of biological products. The type of packaging container material depends on the inherent stability of the stored sample (such as easily oxidized, photosensitive, hygroscopic, volatile, adsorbent, etc.) and the ambient temperature and time to be stored. In general, it is better to choose a container with good sealing and ease of use. and good quality glass bottles or medium-high density polyethylene bottle packaging.
5.3.4 Non-traceable biomass control products at different levels (different concentrations or different contents) should be packaged independently as much as possible. The packaging volume of the minimum packaging unit should be determined based on the measured sampling volume and sample stabilization time, or can also be determined based on the actual needs of the user. 5.4 Uniformity Assessment
5.4.1 In accordance with the provisions of GB/T15000.3, develop a uniformity assessment plan based on the type, preparation process, preparation amount, intended use, usage method, etc. of non-traceable biomass control products. The uniformity assessment plan and the stability assessment plan should be designed simultaneously. 5.4.2 After the non-traceable biological quality control products are packaged into the smallest packaging units, the principle of random sampling or stratified sampling should usually be used for uniformity assessment. The sampling amount, The number of measurements, measurement sequence, data processing, result analysis, etc. should comply with statistical principles. Note: If only sampling inspection is carried out, the required sampling quantity will be very high when conducting homogeneity assessment of non-traceable biomass control products with qualitative characteristics. , which is often not realistic for typical batches of non-traceable biomass controls. Therefore, for non-traceable biomass control products with qualitative characteristics, the purpose of uniformity experimental evaluation may be limited to the inspection of unpredicted gross heterogeneity, while providing information on material sources, processing, and other aspects to support Uniformity assessment conclusion
5.4.3 When the same non-traceable biological quality control product contains multiple measured characteristics, the uniformity and minimum sampling volume of each measured characteristic may be different and should be based on experimental data or experience Sure. When only representative measured characteristics are evaluated for uniformity, evidence regarding the uniformity and minimum sampling size of other measured characteristics can be obtained from the literature and subsequent setting and stability assessments. 5.4.4 When animal and plant quarantine and health quarantine identification laboratories develop biomass control products for morphological identification, a certain number of samples can be taken and sent to a certain number of experts with higher qualifications for identification, and the experts are required to evaluate the quality of the prepared materials. The control products undergo morphological identification, and qualitative results or a certain score are given based on the morphological identification results. The laboratory can determine whether the batch of quality control products is uniform based on the expert judgment results and the described morphological characteristics.
Note: Appendix A gives a reference case for uniformity assessment of morphological biomass control products. 5.4.5 uses different measurement procedures to conduct uniformity assessment. The results may be different. It should be carried out in non-traceable biomass control products. In the product development report, nKaeerKAca-
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explains the measurement procedures and their precision. 5.4.6 The dispersion of results caused by within units, between units, measurement procedures, etc. should be evaluated, and statistical methods should be used to comprehensively judge the degree of impact on the intended use of non-traceable biomass control products (see Appendix B and Appendix C). 5.5 Stability Assessment
5.5.1 According to the provisions of GB/T15000.3, based on the needs and working methods of biometric work, formulate a stability assessment plan. 5.5.2 The transportation stability, post-opening stability or long-term stability of non-traceable biomass control products should be evaluated according to the stability assessment plan, and the corresponding environmental conditions, storage and use requirements should be clarified (see Appendix B and Appendix C). 5.5.3 Evaluating the stability of all characteristic values ??during storage results in high economic and time costs. If the non-traceable biomass control products developed by the laboratory are only for internal use within the laboratory and do not involve transportation issues beyond normal storage conditions, there is no need to conduct transportation stability assessment.
5.5.4 When conducting stability studies on non-traceable biomass control products with qualitative characteristics, samples can be taken at different time points under their storage conditions to observe whether the main parameters or characteristics change. If there is no change or although Any changes will not affect the results of biomass control products and can be considered stable. Appendix A provides a reference case for stability evaluation of morphological biological substance control products. 5.5.5 For non-traceable biological quality control products with multiple tested characteristics, the stability of all tested characteristics can be evaluated through literature, experience or experiments. For non-traceable biomass control products that are reused multiple times, it is valuable to evaluate the stability of opened units. 5.5.6 Use different measurement procedures to conduct stability assessments. The results may be different. It should be done in non-traceable biomass. stated in the control product development report.
5.5.7 When necessary, the validity period of the developed non-traceable biomass control products should be determined based on the stability evaluation results of the characteristic values ??and other background information, and appropriate stability monitoring should be carried out. Stability monitoring can be combined with the application process of quality control products, such as using quality control charts to discover changing trends caused by sample instability.
5.6 Interchangeability assessment (when necessary)
5.6.1 Under normal circumstances, interchangeability assessment of non-traceable biomass control products will not be carried out. If necessary, conduct interchangeability evaluation in accordance with the provisions of WS/T356. The interchangeability of non-traceable biological quality control products only exists between the measurement procedure and the comparative measurement procedure. When any method changes, the interchangeability assessment needs to be re-evaluated. 5.6.2 Before conducting interchangeability assessment, an interchangeability assessment plan should be designed. The plan should clarify the measured characteristics, measurement procedures, comparison procedures, experimental samples, statistical methods, etc.
5.6.3 The test sample and the non-traceable biomass control product to be evaluated should be measured under the same conditions, and the interchangeability should be determined through mathematical correlation.
5.6.4 The impact of measurement environment, storage time, reagent batch number, etc. on different measurement procedures may be different, thus affecting the interchangeability assessment results of non-traceable biological quality control products. When necessary, the impact of changes in measurement environment, storage time, reagent batch numbers, etc. on the interchangeability assessment results of non-traceable biomass control products should be evaluated.
5.7 fixed value
5.7.1 in accordance with GB/T15000.3, select appropriate valuation schemes based on the type, intended use, application method characteristics, and relevant standard requirements of non-traceable biomass control products. If necessary, the complete valuation scheme also includes confirmation of the laboratory's valuation status and quality control plan during the valuation period.
5.7.2 Valuation activities for non-traceable biomass control products should comply with relevant requirements of national laws, regulations, standards, international conventions, etc. on the safety and ethics of biological products.
Note: For non-traceable biomass control products with quantitative characteristics, the total average value of the homogeneity test results can be used as its indicative value, and the standard deviation of the total average value is used to estimate the range of characteristic values. Usually, 2 times and 3 times the standard deviation of the total average value are used as the warning limit and control limit of the quality control chart. Collaborative valuation can also be carried out with no less than 5 sets of independent valuation data/laboratories. If it is not met, the laboratory should evaluate the valuation results through risk assessment. Refer to Appendix C4
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for the quantitative characteristic biomass control product value setting reference case GB/T27424—2020
5.7.3 Qualitative characteristic non-traceable biomass control product, and its value setting method is determined according to the actual situation. It can be determined by the expert group's public discussion or by experimental methods. When the expert public discussion method is used for value setting, it is usually based on the following considerations: a) The corresponding professional ability of the value setting expert;
b) Generally, three or more experts independently evaluate, and at least two or more experts have the same evaluation opinions; c
When multiple experts conduct value setting evaluation, if different experts produce different conclusions on the same result, all members of the expert group can review it, and determine the result and form a record according to the majority principle; d) If necessary, authoritative senior experts can be invited to review. 6 Acceptance
6.1 General requirements
6.1.1 Regardless of the method used to obtain non-traceable biomass control products, they should be accepted before use. 6.1.2 If the amount of non-traceable biomass control products is small and cannot meet the requirements for technical acceptance, or the cost of technical acceptance is too high, the laboratory should conduct a risk assessment on the use of the quality control products, identify possible risks, and take simplified technical acceptance measures. 6.1.3 The laboratory should form a record of the acceptance. The record content includes the name, number, batch number, packaging, label, certificate, characteristic value, validity date, storage date, quantity, manufacturer, acceptance person, acceptance conclusion, etc. If the test technology is used for experimental acceptance, there should also be relevant information such as the test method and test results during the acceptance.
6.1.4 The laboratory should classify and manage the non-traceable biomass control products that have passed the acceptance, clearly mark them, and properly store them. 6.2 Acceptance of self-made non-traceable biomass control products 6.2.1 The research and development personnel should be independent of the acceptance process of non-traceable biomass control products. 6.2.2 The acceptance personnel shall check the development plan, original records of the development process, development report and any information that may affect its use (including biosafety information) to make a judgment on suitability. 6.3 Acceptance of purchased non-traceable biomass control products 6.3.1 It shall be verified whether it meets the requirements of the "Standard Material/Standard Sample Procurement Plan", check the integrity (or sealing degree) of the packaging and labeling, the correspondence between the certificate and the actual product, and understand the characteristic values, matrix composition, validity date, storage conditions, safety protection, special transportation requirements, etc. indicated in the certificate. For non-traceable biomass control products with special transportation requirements such as low temperature, the transportation status shall be checked when feasible. 6.3.2 When necessary and feasible, appropriate experimental methods can be used to verify the characteristic values, matrix composition and other characteristics of non-traceable biomass control products. 6.3.3 When changing the manufacturer or batch of non-traceable biomass control products, it is advisable to compare the new and old quality control products, which can not only verify the stability of the characteristic values ??of the old quality control products, but also confirm that the new quality control products meet the use requirements. 6.4 Acceptance of donated/exchanged non-traceable biomass control products 6.4.1 When the laboratory obtains non-traceable biomass control products through donation or exchange for acceptance, it should request background information and technical information from the other party.
6.4.2 If the above required information can be obtained, the laboratory shall conduct technical acceptance of non-traceable biomass control products obtained through donation or exchange in accordance with 6.3 to evaluate whether the non-traceable biomass control products can be used correctly in this laboratory. 6.4.3 If the above required information cannot be obtained, a risk assessment can be conducted in accordance with the requirements in 6.1.2, and if necessary, the relevant materials required in accordance with 6.2 can be supplemented.
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7 Transportation
7.1 When it is necessary to distribute non-traceable biomass control products within a certain range, it should be ensured that the transportation conditions will not have a negative impact on their characteristic values. If necessary, a transportation stability assessment should be conducted.
7.2 Environmental conditions during transportation should be properly monitored and recorded. 7.3 Biosafety risks caused by spills, leaks and diffusion should be avoided during transportation. 8 Storage
8.1 Non-traceable biomass controls should be safely stored under appropriate conditions based on stability assessment to ensure that their performance parameters are maintained during the validity period.
8.2 Non-traceable biomass controls should be stored in accordance with requirements to ensure that they do not deteriorate or become inactivated due to environmental factors. The packaging of each unit should be sealed and kept away from extreme environments such as high heat, strong light and high humidity. 8.3 Non-traceable biomass controls are usually stored at an appropriate temperature and away from light, such as storing serum-based biomass controls at a low temperature of 80°C.
8.4 The storage environment conditions of non-traceable biomass controls, such as temperature, humidity, illumination, etc., should be monitored regularly to ensure that the storage conditions meet the requirements and be recorded.
8.5 The storage of non-traceable biomass controls with biosafety risks should comply with national laws and regulations and standards. 9 Use
9.1 Regardless of the method of obtaining non-traceable biomass controls, there should be instructions for use. Before use, the instructions should be carefully read, the conditions of use should be verified, biosafety risks should be addressed, and its physical appearance and properties should be verified to meet the experimental requirements. 9.2 When using non-traceable biomass controls, the sampling volume should not be less than the minimum sampling volume. 9.3 For liquid biomass control products, it should be confirmed whether the quality control products can be reused, and attention should be paid to the effects of multiple openings and repeated freezing and thawing operations on homogeneity and stability. They should be fully mixed before each use. 9.4 For solid biomass control products, it should be confirmed that the type and quality of the solvent used meet the requirements, and they should be fully mixed before use; if they are reused, attention should be paid to the effects of multiple openings and repeated freezing and thawing operations on homogeneity and stability. 9.5 During use, if the quality control results are found to be out of control, the laboratory should stop using non-traceable biomass control products, assess the risks, and take necessary corrective measures. If necessary, stop related testing work until the test report is recalled. 10 Disposal
10.1 When non-traceable biomass control products exceed the validity period, or are contaminated or deteriorated during the validity period, they are deemed to be invalid and should be properly labeled and disposed of as soon as possible to avoid misuse.
10.2 For discarded non-traceable biomass control products, especially discarded toxic, harmful, infectious and spreadable biomass control products, they should be destroyed in a safe and prudent manner, or handed over to an institution recognized by the environmental protection department for professional disposal, and a destruction record should be established. 11 Document preparation and identification management
11.1 Document preparation
c11.1.1 When the laboratory develops non-traceable biomass control products by itself, a development report should be prepared. Its contents include but are not limited to: nKaeerKAca-
11.1.2
11.2
Related technical requirements;
Collection and preparation of bulk raw materials;
Type of packaging container used for single unit; Packaging procedure adopted;
Any special stabilization, sterilization or inactivation measures; Supplementary data on relevant materials (such as particle size, moisture content, etc.); Full details of the methods/procedures used in the development: All data obtained from the methods/procedures used in the development: Specific experience to avoid major mistakes or defects in the development of new batches or related quality control products; Any information that affects its use, including biosafety information, etc. GB/T27424—2020
When a laboratory develops non-traceable biomass control products on its own, a description document should be prepared. The contents include, but are not limited to: material name and description;
number and/or batch number;
preparation date;
intended use and special instructions for its use; fixed value (if applicable);
minimum sampling volume (based on homogeneity assessment); storage instructions;
information on expiration date;
special safety precautions, such as biosafety precautions. Labeling management
11.2.1
11.2.2
Laboratories should affix appropriate labels to non-traceable biomass control products, with safety tips and instructions for effective use. The identification information of non-traceable biological substances control products includes but is not limited to: name and description;
serial number and/or batch number:
hazard and safety identification (if necessary);
Environmental conditions, such as temperature, humidity, illumination, etc.; date of preparation or purchase;
expiry date.
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A.1 Collection and Collection of Candidates
Appendix A
(Informative Appendix)| |tt||Example of quality control of morphological specimens
The sources of morphological specimens are divided into two ways: collection and collection. The relevant information of specimens from both sources must be detailed, mainly including: collection place, place of origin or country and region of origin, person and date of collection, collection or interception, appraiser and date, to ensure that the morphological specimens can accurately source, A.2 Processing of materials
Morphological specimens need to be pruned or reshaped, inactivated, dried or soaked in liquid before production. If the insect samples collected are hard, a softening step should be added. At least 10 individuals of the same morphological specimen should be preserved, and a 95% alcohol liquid-immersed morphological specimen should be added to facilitate molecular diagnosis. For samples with less than 95% difference between species, resampling is required to ensure the accuracy and uniformity of the specimens. Old or morphologically different specimens that show no differences after molecular diagnosis can continue to be used, as long as their characteristics are within acceptable limits.
A.3 Preparation
Different types of harmful organisms have different preparation methods of morphological specimens. The main method is to use physical or chemical means to permanently preserve morphological specimens, such as: preparation methods of insect specimens Needle insertion and liquid immersion are mainly used, while two major methods of plant specimen preparation are drying and immersion.
A.4 Uniformity Assessment
The uniformity of each individual specimen is to consider whether it has the typical morphological characteristics of the species. Each specimen should be confirmed by 3 or more industry experts for its typical morphological characteristics to prove that the specimen can represent the species and that its typical morphological characteristics meet the definition requirements of the species.
For the prepared batch specimens, select a certain number of specimens for uniformity assessment, and examine whether the typical characteristics of the selected number of specimens are consistent. Experts are required to confirm that each specimen can represent the species. Typical morphological characteristics meet the definition requirements of this species. A.5 Stability assessment
For morphological specimens that have passed the uniformity assessment, the stability assessment cycle needs to be carried out at 3 months, 6 months and 12 months in the first year, and then once a year. . The main contents of the evaluation are: whether the morphological characteristics are complete, whether there are changes in color, and whether corruption or deterioration has occurred.
A.6 Fixed value
Because the specimen quality control products are mainly descriptions of morphological characteristics, most of them are qualitative results, which can be positive or negative as fixed value results. The value can also be determined by scoring according to the conformity of the morphological characteristics 8
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