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07 Natural and applied sciences
New standards
IEC TS 62607-6-12:2024
Nanomanufacturing - Key Control Characteristics - Part 6-12: Graphene - Number of layers: Raman spectroscopy, optical reflection
Scope:
IEC TS 62607-6-12:2024 establishes a standardized method to determine the key control characteristic
- number of layers
for films consisting of graphene by
- Raman spectroscopy and
- optical reflection.
Criteria for the determination of the number of layers are the G-peak integrated intensity and the optical contrast. Both methods enable to distinguish between graphene and multilayer graphene. However, neither method on its own nor the combination of the two enable a determination of the number of layers in all possible cases (especially regarding all possible stacking angles). But the comparison of the values deduced by each method allows to discriminate whether the determined number of layers is correct and can be specified or not.
- The method is applicable to exfoliated graphene and graphene grown on or transferred to a substrate with a small defect density, low surface contamination (e.g. transfer residue) and number of layers up to 5.
- The method is suitable for the following substrates:
a) glass (soda lime glass or similar with a refractive index between 1,45 and 1,55 at 532 nm);
b) oxidized silicon (SiO2 on silicon, with a SiO2 thickness of 90 nm ± 5 nm).
- The spatial resolution is in the order of 1 µm given by the spot size of the exciting laser.
- number of layers
for films consisting of graphene by
- Raman spectroscopy and
- optical reflection.
Criteria for the determination of the number of layers are the G-peak integrated intensity and the optical contrast. Both methods enable to distinguish between graphene and multilayer graphene. However, neither method on its own nor the combination of the two enable a determination of the number of layers in all possible cases (especially regarding all possible stacking angles). But the comparison of the values deduced by each method allows to discriminate whether the determined number of layers is correct and can be specified or not.
- The method is applicable to exfoliated graphene and graphene grown on or transferred to a substrate with a small defect density, low surface contamination (e.g. transfer residue) and number of layers up to 5.
- The method is suitable for the following substrates:
a) glass (soda lime glass or similar with a refractive index between 1,45 and 1,55 at 532 nm);
b) oxidized silicon (SiO2 on silicon, with a SiO2 thickness of 90 nm ± 5 nm).
- The spatial resolution is in the order of 1 µm given by the spot size of the exciting laser.
Base documents:
ISO 7383-2:2024
Fine bubble technology — Evaluation method for determining gas content in fine bubble dispersions in water — Part 2: Hydrogen content
Scope:
This document specifies the evaluation methods for hydrogen content in ultrafine bubble (UFB) dispersions.
The titration (oxidimetry) method can be used as a quick method to estimate the hydrogen content in hydrogen UFB dispersions. The lower limit of detection is 0,1 mg/l, and the range with acceptable accuracy is between 0,2 mg/l and 1,6 mg/l. The existence of oxidizing or reducing substances in dispersions influences measurement accuracy.
The gas chromatographic method features a considerably high accuracy range and lower limit of detection. The existence of UFBs in water does not influence the measurement results. The existence of oxidizing or reducing substances in water does not affect the measurement accuracy either. However, the measurement procedure is time consuming.
NOTE This document only provides a method for determining hydrogen contents in UFB dispersions and does not involve the specific effects of hydrogen UFB dispersion application.
The titration (oxidimetry) method can be used as a quick method to estimate the hydrogen content in hydrogen UFB dispersions. The lower limit of detection is 0,1 mg/l, and the range with acceptable accuracy is between 0,2 mg/l and 1,6 mg/l. The existence of oxidizing or reducing substances in dispersions influences measurement accuracy.
The gas chromatographic method features a considerably high accuracy range and lower limit of detection. The existence of UFBs in water does not influence the measurement results. The existence of oxidizing or reducing substances in water does not affect the measurement accuracy either. However, the measurement procedure is time consuming.
NOTE This document only provides a method for determining hydrogen contents in UFB dispersions and does not involve the specific effects of hydrogen UFB dispersion application.
Base documents:
ISO 7218:2024
Microbiology of the food chain — General requirements and guidance for microbiological examinations
Scope:
This document specifies general requirements and gives guidance on microbiological examinations.
It is applicable to:
— the implementation of specific horizontal or vertical International Standards developed by ISO/TC 34/SC 9 or ISO/TC 34/SC 5 for detection or enumeration of microorganisms, named hereafter “specific standards”;
— good laboratory practices for microbiology laboratories testing samples from the food chain;
— guidance for microbiological laboratories testing samples from the food chain on the technical requirements for conforming to ISO/IEC 17025.
The requirements of this general standard supersede corresponding ones in existing specific standards.
Additional instructions for examinations using the polymerase chain reaction (PCR) are specified in ISO 22174.
This document is applicable to examinations for bacteria, yeasts and moulds and can be used, if supplemented with specific guidance, for parasites and viruses. It does not apply to examinations for toxins or other metabolites (e.g. amines) from microorganisms.
This document is applicable to microbiology of the food chain, from primary production stage to food and animal feed products, including the premises where the food or feed production and handling takes place. It is also applicable to the microbiological examination of water where water is used in food production or is regarded as a food in national legislation.
It is applicable to:
— the implementation of specific horizontal or vertical International Standards developed by ISO/TC 34/SC 9 or ISO/TC 34/SC 5 for detection or enumeration of microorganisms, named hereafter “specific standards”;
— good laboratory practices for microbiology laboratories testing samples from the food chain;
— guidance for microbiological laboratories testing samples from the food chain on the technical requirements for conforming to ISO/IEC 17025.
The requirements of this general standard supersede corresponding ones in existing specific standards.
Additional instructions for examinations using the polymerase chain reaction (PCR) are specified in ISO 22174.
This document is applicable to examinations for bacteria, yeasts and moulds and can be used, if supplemented with specific guidance, for parasites and viruses. It does not apply to examinations for toxins or other metabolites (e.g. amines) from microorganisms.
This document is applicable to microbiology of the food chain, from primary production stage to food and animal feed products, including the premises where the food or feed production and handling takes place. It is also applicable to the microbiological examination of water where water is used in food production or is regarded as a food in national legislation.
Base documents:
Replaced standards
ISO 7218:2007
Microbiology of food and animal feeding stuffs -- General requirements and guidance for microbiological examinations
Scope:
ISO 7218:2007 gives general requirements and guidance/options intended for three main uses:
implementation of ISO TC34/SC9 or TC34/SC5 standards for detection or enumeration of microorganisms;good laboratory practices for food microbiological laboratories (the purpose is not to detail them in this International Standard, manuals are available for that purpose);guidance for accreditation of food microbiological laboratories (this International Standard describes the technical requirements according to Appendix B of ISO/IEC 17025:2005 for the accreditation of a microbiological laboratory by national organizations).
ISO 7218:2007 covers examination for bacteria, yeasts and moulds and can be used if supplemented with specific guidance for prions, parasites and viruses. It does not cover the examination for toxins or other metabolites (e.g. amines) from microorganisms.
It applies to the microbiology of food, animal feeding stuffs, the food production environment and the primary production environment.
The purpose of ISO 7218:2007 is to help to ensure the validity of food microbiology examinations, to assist in ensuring that the general techniques used for conducting these examinations are the same in all laboratories, to help achieve homogeneous results in different laboratories, and to contribute towards the safety of the laboratory personnel by preventing risks of infection.
implementation of ISO TC34/SC9 or TC34/SC5 standards for detection or enumeration of microorganisms;good laboratory practices for food microbiological laboratories (the purpose is not to detail them in this International Standard, manuals are available for that purpose);guidance for accreditation of food microbiological laboratories (this International Standard describes the technical requirements according to Appendix B of ISO/IEC 17025:2005 for the accreditation of a microbiological laboratory by national organizations).
ISO 7218:2007 covers examination for bacteria, yeasts and moulds and can be used if supplemented with specific guidance for prions, parasites and viruses. It does not cover the examination for toxins or other metabolites (e.g. amines) from microorganisms.
It applies to the microbiology of food, animal feeding stuffs, the food production environment and the primary production environment.
The purpose of ISO 7218:2007 is to help to ensure the validity of food microbiology examinations, to assist in ensuring that the general techniques used for conducting these examinations are the same in all laboratories, to help achieve homogeneous results in different laboratories, and to contribute towards the safety of the laboratory personnel by preventing risks of infection.
Base documents:
Replaced:
ISO 7218:2024
Drafts
prEN 12469-5
Biological safety cabinets - Part 5: Installation, commissioning and routine testing
Scope:
This document gives requirements and recommendations for installation, commissioning and routine testing of BSC.
Base documents:
prEN 12469-5
prEN 12469-2
Biological safety cabinets - Part 2: BSC class II
Scope:
This document specifies the specific requirements for class II BSC with respect to design, construction, safety and hygiene.
It sets the specific performance criteria for class II BSC for work with biological agents and specifies test procedures with respect to protection of the worker, the environment and product protection including cross-contamination.
It sets the specific performance criteria for class II BSC for work with biological agents and specifies test procedures with respect to protection of the worker, the environment and product protection including cross-contamination.
Base documents:
prEN 12469-2
prEN 12469-1
Biological safety cabinets - Part 1: Classes and basic requirements
Scope:
This document specifies the minimum requirements for BSC with respect to design, construction, safety and hygiene and gives general test methods for their verification.
The requirements for the different classes are given in the respective parts of prEN 12469.
The requirements for the different classes are given in the respective parts of prEN 12469.
Base documents:
prEN 12469-1