CHAPTER 5

International standards
in nanotechnologies
Charles A. Clifforda, Michael Stinzb, Vasile-Dan Hodoroabac,
Wolfgang
a
E.S. Ungerc, Toshiyuki Fujimotod
National Physical Laboratory, Teddington, United Kingdom
b
Technische Universit€at Dresden, Dresden, Germany
c
€r Materialforschung und -pr€
Bundesanstalt f u ufung (BAM), Berlin, Germany
d
National Metrology Institute of Japan (NMIJ), National Institute of Advanced Industrial Science and Technology (AIST),
Tsukuba, Japan

Introduction
There has been much written about the so-called reproducibility crisis [1] with failure to
reproduce the results of an experiment reported by more than half of the physicists and
chemists surveyed. Some of the factors that increase reproducibility and reliability include
metrology [2] and documentary standards. Measurement and characterization documen-
tary standards enable scientists to follow a method or procedure to arrive at a measure-
ment result. This chapter provides an overview of international standardization activities
in nanotechnologies with a focus on measurement standards.

What is a standard?
There are two types of standards: documentary standards and reference materials. The
former is the subject of this chapter. Concerning the later, a reference material is a mate-
rial that has a known specified property that is provided, for example, in the form of a
certificate or data sheet. The material should also be sufficiently homogenous and stable
for that property over a specified time. Reference materials are typically used to calibrate a
measurement method. This could be done in combination with a documentary standard,
which provides the method to undertake the calibration. Reference materials can also be
used to validate results and measurement procedures. Reference materials are of primary
importance in validating measurement results and are covered, as necessary, in other
chapters of the book, but are not the subject of this chapter.
A standard is defined by ISO as a ‘document, established by consensus and approved
by a recognized body, that provides, for common and repeated use, rules, guidelines or
characteristics for activities or their results, aimed at the achievement of the optimum
degree of order in a given context’ [3]. A standard is developed by a committee in a

Characterization of Nanoparticles © 2020 Elsevier Inc.

https://doi.org/10.1016/B978-0-12-814182-3.00026-2 All rights reserved. 511
512 Characterization of nanoparticles

recognized body such as ISO or ASTM. It is developed not only by one person but also
by a group of people, who are experts in their field who come to agreement on the text of
the standard.

Why standardize?
Standards represent the current best practice in a particular application or field as they are
made by experts in the field who work together to achieve consensus from all stake-
holders. Standards allow results to be compared. Hence, by following a standard, results
taken on one day are comparable with those taken on subsequent days. In addition, results
taken on different instruments, in different laboratories, or by different people around the
world should be comparable. Therefore, while there may be an initial cost to comply
with standards, organizations save significant time and money in the long run by com-
piling with standards. There can also be a cost, sometimes hidden, of not complying with
standards with the loss of market, market share, and opportunities. Standards are volun-
tary; they do not have to be used, but often, they can form the basis of regulations or be
referred to in regulations.
For the ongoing commercialization and sales of nano-objects, there are two para-
digms forming. These are (i) high volume and low cost and (ii) highly specialized
(and hence likely lower volume and higher cost).
For high-volume manufacture, production volume can often outstrip application
need, and a clear application may not be established. This leads to a race amongst man-
ufacturers to provide the lowest price, which leads to lower quality. Here, standards are
needed for quality and assurance within the supply chain.
For highly specialized nano-objects, the properties of the nano-objects are tailored to
an application. Hence, the particles will have one or more of the following properties:
highly specific size and/or shape, specific chemistry or surface chemistry, and charge.
Here, standards are needed to verify these properties and make sure they are within
the tolerances necessary for the performance of the nano-objects.

Route to standardization
Fig. 1 shows the typical development of standard in measurement and characterization.
The first step is method development, or research into solving a particular problem. This
is likely to lead to a publication that has been peer-reviewed or a patent application if the
solution has significant commercial value. The method should then be verified further to
investigate repeatability. Does the method produce the same result on difference days
using the same equipment and same samples? What about different operators?
The method should then be checked to see whether it is reproducible. For example,
following the same methods and using similar or the same samples, is it possible for
 International standards in nanotechnologies 513

Fig. 1 Step-by-step process on the typical development of a measurement standard.

different laboratories using different operators and different equipment to produce the
same or comparable results? The best way to test this is via an interlaboratory study.
In such a study, each lab is provided with a sample and a procedure to follow, and
the results from multiple laboratories are compared. If the comparability in results is
acceptable, this procedure could then be turned into a draft ISO standard. It is useful
to conduct interlaboratory studies through organizations dedicated to such activities
and follow the guidance that they can provide. A prime example of this is the Versailles
Project on Advanced Materials and Standards (VAMAS).
VAMAS was established in 1982 and now has 15 member countries including the
United Kingdom, the United States, China, Japan, and India. The main objective of
VAMAS is to promote world trade by innovation and adoption of advanced materials.
It enables this through international collaborations that provide the technical basis for the
harmonization of measurement methods, leading to best practices and international
standards.
VAMAS consists of a number of technical working areas (TWAs) that undertake
interlaboratory studies in different application areas or techniques. There are a number
of TWAs relevant to nanotechnologies, and these along with example interlaboratory
studies that have been completed or are currently underway are shown in Table 1.
As shown in Fig. 1, after research and validation via an international interlaboratory
study and a good draft standard, the next step in the standardization process is for a mem-
ber country to submit a new work item proposal consisting of a form explaining the pur-
pose and relevance of the standard and a draft ISO standard. Prior to this submission, in
ISO/TC 229/JWG2 (Nanotechnologies: measurement and characterization), project
leaders are invited to submit a metrology checklist along with the documentation. This
checklist is designed to aid the project leader in the preparation of a new work item.
514 Characterization of nanoparticles

Table 1 VAMAS technical working areas (TWA) and example current projects in these TWAs
of relevance to nanotechnologies standardization
VAMAS TWA Example current projects
TWA 2 Surface chemical Guidelines for shape and size analysis of nanoparticles by
analysis atomic force microscopy
XPS intensity calibration with poly(ethylene)
TWA 34 Nanoparticle Interlaboratory study of the measurement of number
populations concentration of colloidal nanoparticles
Assessment of methods for particle size distribution evaluation
via field-flow fractionation (FFF) techniques
TWA 41 Graphene and Elemental analysis and oxygen content of a graphene powder
related 2D materials (XPS)
Thickness measurements of graphene oxide flakes (AFM)
TWA 42 Raman spectroscopy Raman spectroscopy for TiO2 nanoparticle mixtures
and microscopy Measurement of lateral and axial resolution of a Raman
microscope

It contains nine questions concerning amongst other things validation, availability of

equipment, measurands, and measurement uncertainty.
A new work item proposal in ISO is balloted by experts from member countries
inviting their initial comments and the appointment of named experts to assist in the
development of the standard. If the draft is approved in the ballot, it becomes a ‘new work
item’, and will then progress through a series of discussions, commenting stages, and offi-
cial votes to obtain a consensus amongst the experts on the text and contents of a draft
standard.
There are three main types of ISO outputs: full international standards, technical spec-
ifications, and technical reports. A technical specification (TS) is a short-term type of
standard that addresses work still under technical development. Many of the outputs
in nanotechnology standardization are currently technical specifications. A technical
report (TR) contains information of a different kind from that of standards or specifica-
tions. It may include an informative report, or information of the perceived state of the art
in an area of importance to the technical committee.

Nanotechnologies standards committees

At the beginning of this century, an increase in the deliberate application of nanotech-
nology to commercial products was starting. Alongside this activity, there was a growing
demand for the standardization of nanotechnologies. To meet this demand, ISO estab-
lished a new technical committee for nanotechnology, TC229, in 2005. About the same
time, ASTM, IEC, and CEN also formed nanotechnology standardization committees.
Table 2 provides information on these committees.
 International standards in nanotechnologies 515

Table 2 Summary of standardization committees focused on nanotechnologies

Standards
Published under
Committee Founded Membership standards development
ISO/TC 229 2005 37 Participating 72 40
Nanotechnologies countries
14 Observing
countries
CEN/TC 352 2005 34 Countries 21 9
Nanotechnologies

IEC TC 113 2006 15 Participating 27 35

Nanotechnology countries
for 19 Observer
electrotechnical countries
products and
systems
ASTM 2005 Over 180 18 8
International TC members
E56
Nanotechnology

The scope of the ISO/TC 229 is as follows:

Standardization in the field of nanotechnologies that includes either or both of the following: 1)
Understanding and control of matter and processes at the nanoscale, typically, but not exclusively,
below 100 nanometres in one or more dimensions where the onset of size-dependent phenomena
usually enables novel applications. 2) Utilizing the properties of nanoscale materials that differ
from the properties of individual atoms, molecules, and bulk matter, to create improved materials,
devices, and systems that exploit these new properties. Specific tasks include developing standards
for: terminology and nomenclature; metrology and instrumentation, including specifications for
reference materials; test methodologies; modelling and simulations; and science-based health,
safety, and environmental practices.

ISO/TC 229 consists currently of five working groups on: terminology; measurement and
characterization; health, safety and environment; material specification; and products and
applications. The standards developed by ISO/TC 229 reflects those working groups.
The scope of the JWG2 on measurement and characterization is ‘The development of
516 Characterization of nanoparticles

standards for measurement, characterization and test methods for nanotechnologies, taking
into consideration needs for metrology and reference materials’.
In 2006, IEC also established a technical committee for nanotechnology, IEC/TC
113, on electrotechnical applications. To avoid inconsistency of standards from both
committee and to save standardization global resources, ISO and IEC agreed to develop
a standard jointly in the fields of terminology and measurement and characterization.
To guide users to choose the correct technique to measure a desired physical or chem-
ical parameter, ISO/TC 229/JWG2 developed the technical report ‘Nanotechnol-
ogies—Measurement technique matrix for the characterization of nano-objects’ (ISO
TR 18196). There are many different properties or measurands that are required for char-
acterization of nano-objects, including size, shape, chemistry, and charge. It is important
to know the details of the exact measurand that the selected techniques will provide.
Hence, ‘Guidance on measurands for characterising nano-objects and materials that con-
tain them’ was developed. This was first published by CEN/TC 352 (European nano-
technologies) and is now under development internationally in ISO/TC 229/JWG2.
This contains sections on most of the techniques covered in this book.
Size and size distribution measurements of nano-objects are essential to support cur-
rent and future legislation in nanotechnologies, for example, with the introduction of a
‘nanomaterial’ definition by the European commission in 2011. For size and size distri-
bution evaluation measurement method standards including sample preparation are
essential. In 2020, standards in the measurement of nanoparticle size and shape using
TEM and SEM will be published by ISO/TC 229.
As well as terminology and measurement methods, a further important need in cur-
rent nanotechnology standardization is risk management and environment, health, and
safety standards. Standardization in exposure and hazard quantification are becoming
increasingly important. This in turn leads to the central question of the nanomaterial def-
inition for regulatory purposes and their relation to toxicological and exposure studies.
As part of these studies, detailed measurement and characterization of the nano-objects is
essential.

Terminology
Nanotechnologies involve interactions between people from different fields and different
backgrounds. For example, it involves scientists, regulators, toxicologists, industrialists,
and people from academia. Nanotechnologies are also crosscutting across many industry
and application areas so naturally involve materials scientists, biologists, chemists, and
physicists.
To avoid any mistakes or misunderstanding and to facilitate reliable exchange of
information, it is essential that all people involved in this field use the same terminology.
A common set of terms and their definitions are thus essential.
 International standards in nanotechnologies 517

Table 3 ISO terminology standards related to nanotechnologies from four ISO committees
ISO/TC 229 Nanotechnologies
ISO TS 80004-1:2015 Nanotechnologies—Vocabulary—Part 1: Core terms
ISO TS 80004-2:2015 Nanotechnologies—Vocabulary—Part 2: Nano-objects
ISO TS 80004-3:2010 Nanotechnologies—Vocabulary—Part 3: Carbon nano-objects
ISO TS 80004-4:2011 Nanotechnologies—Vocabulary—Part 4: Nanostructured materials
ISO TS 80004-5:2011 Nanotechnologies—Vocabulary—Part 5: Nano/bio interface
ISO TS 80004-6:2013 Nanotechnologies—Vocabulary—Part 6: Nano-object characterization
ISO TS 80004-7:2011 Nanotechnologies—Vocabulary—Part 7: Diagnostics and therapeutics for
healthcare
ISO TS 80004-8:2013 Nanotechnologies—Vocabulary—Part 8: Nanomanufacturing processes
IEC TS 80004-9:2017 Nanotechnologies—Vocabulary—Part 9: Nano-enabled electrotechnical
products and systems
ISO TS 80004-11:2017 Nanotechnologies—Vocabulary—Part 11: Nanolayer, nanocoating,
nanofilm, and related terms
ISO TS 80004-12:2016 Nanotechnologies—Vocabulary—Part 12: Quantum phenomena in
nanotechnology
ISO TS 80004-13:2017 Nanotechnologies—Vocabulary—Part 13: Graphene and related two-
dimensional (2D) material
ISO TR 18401:2017 Nanotechnologies—Plain language explanation of selected terms from the
ISO/IEC 80004 series
ISO/TC 201 Surface Chemical Analysis
ISO 18115-1:2013 Surface chemical analysis—Vocabulary—Part 1: General terms and terms used
in spectroscopy
ISO 18115-2:2013 Surface chemical analysis—Vocabulary—Part 2: Terms used in scanning-
probe microscopy
ISO WD 18115-3 [Under development] Surface chemical analysis—Vocabulary—Part 3: terms
used in optical interface analysis
ISO/TC 24/SC 4 Particle Characterization
ISO 26824:2013 Particle characterization of particulate systems—Vocabulary
ISO/TC 202 Microbeam Analysis
ISO 22493:2014 Microbeam analysis—Scanning electron microscopy—Vocabulary
ISO 15932:2013 Microbeam analysis—Analytical electron microscopy—Vocabulary

To meet this need, the ISO technical committees have developed terminology stan-
dards; these standards are summarized in Table 3.
In addition, ISO have made available for free all ISO developed terms and definitions.
These are available online via the ISO online browsing platform (OBP) www.iso.org/
obp. Here, users can search for specific terms and see the ISO definitions and also search
for standards and be able to browse the terms and definitions sections of any standard for
free. Hence, the standards listed in Table 3 can be viewed for free online via the ISO
OBP. Example terms and definitions are as follows:
518 Characterization of nanoparticles

Nanoscale
Length range approximately from 1 to 100 nm.
Note 1 to entry: Properties that are not extrapolations from larger sizes are predom-
inantly exhibited in this length range.
Nano-object
Discrete piece of material with one, two, or three external dimensions in the
nanoscale.
Note 1 to entry: The second and third external dimensions are orthogonal to the
first dimension and to each other.

Sample preparation standards

Sample preparation information is usually included as part of the measurement standard,
but recently, ISO/TC 201 have also published ISO 20578-4: Surface Chemical
Analysis—Sample handling, preparation and mounting—Part 4—Reporting informa-
tion related to the history, preparation, handling and mounting of nano-objects prior
to surface analysis. This is focused on surface chemical analysis but does contain informa-
tion applicable to all types of analyses. The standard identifies information to be reported
regarding the handling of nano-objects in preparation for surface chemical analysis. This
is required to assure reliability and reproducibility of analyses. It introduces the necessity
to provide provenance information as nano-objects and the environment they are in are
likely to change over time. So, the source of the material needs to be recorded along with
changes that have taken place since the sample was originated. These should become part
of the data record. Three annexes are included in ISO 20578-4. Annex A summarizes
challenges associated with nano-objects that highlight the need for increased documen-
tation and reporting. Annex B provides examples of methods commonly used to extract
particles from a solution for surface chemical analysis, and Annex C provides an example
sample information form and data.
There is also a general standard on powder preparation for electron microscopy
(ISO 20720:2018) as detailed in the next section.

Electron microscopies
Electron microscopy techniques, particularly scanning electron microscopy (SEM) and
transmission electron microscopy (TEM), offer the ability to image particle by particle
the size and shape of nanoparticle, nanotubes, and other objects. Standards in electron
microscopies are developed in various ISO technical committees covering various aspects
as shown in Table 4.
 International standards in nanotechnologies 519

Table 4 Selected electron microscopy standards relevant to nanotechnologies

Standard Committee Technique(s) Material
ISO 20720:2018 Microbeam analysis— ISO/TC 202 WDS, EDS Powders
Methods of specimen preparation for with SEM
analysis of general powders using WDS
and EDS
ISO 25498:2018 Microbeam analysis— ISO/TC 202 SAED in Crystalline
Analytical EM—Selected area electron TEM nano-objects
diffraction analysis using a TEM
ISO 16700:2016 Microbeam analysis— ISO/TC 202 SEM General
SEM—Guidelines for calibrating image
magnification
ISO TS 10798:2011 Nanotechnologies— ISO/TC 229 SEM Single-wall
Characterization of single-wall carbon carbon
nanotubes using SEM and EDS nanotubes
ISO DIS 21363 Nanotechnologies— ISO/TC 229 TEM Nanoparticles
Measurements of particle size and shape
distributions by TEM
ISO DIS 19749 Nanotechnologies— ISO/TC 229 SEM Nanoparticles
Measurements of particle size and shape
distributions by SEM
ISO TS 10797:2012 Nanotechnologies— ISO/TC 229 TEM Single-wall
Characterization of single-wall carbon carbon
nanotubes using TEM nanotubes
ISO TS 21361:2019 Nanotechnologies— ISO/TC 229 TEM with Carbon black
Method to quantify air concentrations of EDS and amorphous
nanoparticle carbon black and amorphous silica
silica in a mixed dust manufacturing
environment

Scanning probes
Like electron microscopy techniques, scanning probes offer the ability to image at the
nanoscale and to image nano-objects particle by particle. Standardization is covered
by ISO/TC 201/SC9 scanning probe microscopy and selected standards from this com-
mittee are shown in Table 5.

Suspension based size measurement methods

Standards in nano-object size measurement are developed both in an instrument-specific
committee, ISO/TC 24/SC 4 ‘Particle Characterization’, and, in liaison with that com-
mittee, in the more ‘horizontal’ material-based committees of ISO/TC 229 ‘Nanotech-
nologies’ and CEN/TC 352 ‘Nanotechnologies’. ISO/TC 24/SC 4 has published
520 Characterization of nanoparticles

Table 5 Selected scanning probe microscopy standards relevant to nanotechnologies

Standard Committee Technique(s) Material
ISO 11039:2012—SPM—Measurement of ISO/TC 201/SC9 AFM General
drift rate
ISO 11775:2015 SPM—Determination of ISO/TC 201/SC9 AFM General
cantilever normal spring constants
ISO 11952:2019 SPM—Determination of ISO/TC 201/SC9 AFM General
geometric quantities using SPM:
Calibration of measuring systems
ISO 13095:2014 AFM—Procedure for ISO/TC 201/SC9 AFM General
in situ characterization of AFM probe shank
profile used for nanostructure measurement

47 standards including standards on small-angle X-ray scattering, laser diffraction

method, and electrophoretic aerosol mobility method standards and zeta-potential deter-
mination. In CEN/TC 113 and ISO/TC 229, standards have been published on specific
particle characterization methods like field-flow fractionation in combination with cen-
trifugation (ISO TS 21362) and on a general framework for determining airborne release
of nano-objects from nanostructured powders by means of aerosol analysis (ISO
TS 12025).
The basis of particle analyses is a consistent representation of particle measurement
results. For this purpose, ISO 9276 was developed by the ISO/TC 24/SC 4. It consists
of six parts and addresses the graphical representation of size distributions, the calculation
of mean diameters, the fit to distribution models, the characterization of classification
processes, the properties of logarithmic normal distributions, and a collection of
macro- and mesoshape descriptors.
The detection of nano-objects in complex liquid matrices is challenging with mul-
tiple background components. Detection of manufactured nano-objects in such media
requires more information than just the size of the particles. For each particle, two mea-
surands must be combined: the size (for classification as a nano-object) and also the ele-
mental composition (to discriminate the target particles with an a priori known elemental
composition or morphology, from the matrix and background particles). This can also be
supported, for example, by additional morphology characterization. CEN/TS 17273
details this using the methods field-flow fractionation, single-particle inductively coupled
plasma mass spectrometry and SEM.
For health and safety reasons, airborne nanoparticulate release is important to con-
sider. ISO/TC 229 has developed as a first step the technical specification (TS) ISO
TS 12025, which is a general framework for determining airborne release of nano-objects
from nanostructured powders. For pigmented coating and plastic community, ISO/TC
 International standards in nanotechnologies 521

256 has developed ISO 21683 on ‘Nanotechnological properties of pigments and

extenders’. It describes defined scenarios for release testing with regard to sensitivity
and reproducibility of standardized particle measurement methods.
A summary of size measurement method standards and measurement of other mea-
surands is given in Tables 6 and 7.

Surface area
Standards involving the measurement of specific surface area are shown in Table 8.

Surface chemical analysis

The first international standardization activities in the field of surface chemical analysis
were launched by ASTM International. Later in 1993, ISO/TC 201 Surface chemical
analysis was founded, which develops the vast majority of the standards in this area. Stan-
dards have been published on terminology, on calibration of instruments used in surface
chemical analysis, on reporting results that are applicable in wider fields of technology and
also technical reports on applications in the emerging field of nanotechnology. More
recently, specific applications in nanotechnology are dealt with by ISO/TC 229, and
CEN/TC 352 founded to focus on requests from nanotechnologies. Examples are stan-
dards for the characterization of graphene and other 2-D nanomaterials or Au
nanoparticles.
Because of the increasing demand for more quantitative applications of surface chem-
ical analysis, there is a strong impetus to develop standards to enable comparable quan-
titative results obtained by methods of surface chemical analysis in different laboratories
worldwide.
ISO/TC 201 has instrument-specific subcommittees on electron spectroscopies
(XPS, AES), secondary ion mass spectrometry (SIMS), glow discharge spectroscopy,
scanning probe microscopy (SPM), and X-ray reflectometry (XRR) and X-ray fluores-
cence (XRF) analysis as well as general subcommittees looking at terminology, general
procedures, depth profiling, and data management, standards of which are shown in
Table 9. It has working groups looking at nanomaterial, biomaterial, and optical interface
analysis. There are currently no international standards in ion scattering methods of RBS
and LEIS.

Material specific standards

Standards can be instrument specific and material unspecific, but they can also be material
specific, and in those cases, many methods to characterize one particular material can be
covered in the same standard. When ISO/TC 229/JWG2 started, their programme had a
focus on carbon nanotubes (CNTs). CNT measurement standards were developed for
522 Characterization of nanoparticles

Table 6 Selected size measurement method standards relevant to nanotechnologies

Standard Committee Technique(s) Material
ISO/TS 21362:2018 Nanotechnologies— ISO/TC FFF and NOAA
Analysis of nano-objects using asymmetrical 229 DCS
flow and centrifugal field-flow fractionation
ISO/TS 19590:2017 Size distribution and ISO/TC Sp-ICPMS Nano-objects
concentration of inorganic nanoparticles in 229
aqueous media via single-particle ICP-MS
ISO 22412:2017 Particle size analysis— ISO/TC DLS Nano-objects
Dynamic light scattering (DLS) 24/SC4
ISO 19430:2016 Particle size analysis— ISO/TC PTA NOAA
Particle tracking analysis (PTA) method 24/SC4
ISO 17867:2015 Particle size analysis—Small- ISO/TC SAXS NOAA
angle X-ray scattering 24/SC4
ISO 13318-1:2001 Determination of particle ISO/TC CS NOAA
size distribution by centrifugal liquid 24/SC4
sedimentation methods—Part 1: General
principles
ISO 13318-2:2007 Determination of particle ISO/TC CS NOAA
size distribution by centrifugal liquid 24/SC4
sedimentation methods—Part 2:
Photocentrifuge method
ISO 20998-1:2006 Measurement and ISO/TC USS NOAA
characterization of particles by acoustic 24/SC4
methods—Part 1: Concepts and procedures in
ultrasonic attenuation spectroscopy
ISO 20998-2:2013 Measurement and ISO/TC USS NOAA
characterization of particles by acoustic 24/SC4
methods—Part 2: Guidelines for linear theory
Aerosol based size measurement methods
ISO 15900:2009 Determination of particle size ISO/TC DEMA Nano-objects
distribution—Differential electrical mobility 24/SC4
analysis for aerosol particles
ISO 27891:2015 Aerosol particle number ISO/TC CPC Nano-objects
concentration—Calibration of condensation 24/SC4
particle counters
ISO/TS 12025:2012 Nanomaterials— ISO/TC DEMA, Nano-objects
Quantification of nano-object release from 229 CPC
powders by generation of aerosols
ISO 21683:2019 Pigments and extenders— ISO/TC DEMA, Nano-objects
Determination of experimentally simulated 256 CPC
nano-object release from paints, varnishes and
pigmented plastics
NOAA, nano-objects and their agglomerates and aggregates.
 International standards in nanotechnologies 523

Table 7 Selected method standards measuring various measurands of nano-objects in suspension

as described in other chapters
Standard Committee Technique(s) Material
ISO 13099-1:2012 Methods for zeta-potential ISO/TC CVP, ELS NOAA
determination—Part 1: Electroacoustic and 24/SC4
electrokinetic phenomena
ISO 13099-2:2012 Methods for zeta-potential ISO/TC ELS NOAA
determination—Part 2: Optical methods 24/SC4
ISO 13099-3:2014 Methods for zeta-potential ISO/TC CVP NOAA
determination—Part 3: Acoustic methods 24/SC4
ISO/TS 10868:2017 Characterization of ISO/TC UV–Vis– Single-wall
single-wall CNT using ultraviolet-visible- 229 NIR carbon
near infrared (UV–Vis–NIR) absorption nanotubes
spectroscopy
CEN/TS 17273:2019 Guidance on detection CEN/TC EM, FFF, Nano-objects
and identification of nano-objects in complex 352 spICPMS
matrices

Table 8 Selected standards in specific surface area measurement relevant to nanotechnologies

Standard Committee Technique(s) Material
ISO 9277:2010 Determination of the specific ISO/TC BET Nano-
surface area of solids by gas adsorption—BET 24/SC 4 objects
method
ISO 15901-1:2016 Evaluation of pore size ISO/TC Mercury Nano-
distribution and porosity of solid materials by 24/SC 4 porosimetry, gas objects
mercury porosimetry and gas adsorption— adsorption
Part 1: Mercury porosimetry
ISO 15901-2:2006 Pore size distribution and ISO/TC Gas adsorption NOAA
porosity of solid materials by mercury 24/SC 4
porosimetry and gas adsorption—Part 2:
Analysis of mesopores and macropores by gas
adsorption
ISO 15901-3:2007 Pore size distribution and ISO/TC Gas adsorption Nano-
porosity of solid materials by mercury 24/SC 4 objects
porosimetry and gas adsorption—Part 3:
Analysis of micropores by gas adsorption

each measurement method as a technical specification; examples are TEM (ISO/TS

10797:2012), SEM and EDS (ISO/TS 10798:2011), near-infrared photoluminescence
spectroscopy (ISO/TS 10867:2010), ultraviolet-visible-near infrared (UV–Vis–NIR)
absorption spectroscopy (ISO/TS 10868:2017), evolved gas analysis/gas chromatograph–
mass spectrometry (ISO/TS 11251:2010), and thermogravimetric analysis (ISO/TS
11308:2011).
524 Characterization of nanoparticles

Table 9 Selected standards in surface chemical analysis techniques relevant to nanotechnologies

Standard Committee Technique(s) Material
Electron spectroscopies and SIMS
ISO TR 14187:2011 Surface chemical ISO/TC 201 XPS, AES, Nanostructured
analysis—Characterization of SIMS, etc. materials
nanostructured materials
ISO 10810:2010 Surface chemical ISO/TC 201 XPS General
analysis—XPS—Guidelines for analysis
ISO 20903:2019 Surface chemical ISO/TC 201 XPS, AES General
analysis—AES and XPS—Methods used
to determine peak intensities and
information required when reporting
result
ISO 13084:2018 SIMS—Calibration of ISO/TC SIMS General
the mass scale for a time-of-flight SIMS 201/SC6
ISO 17862:2013 SIMS—Linearity of ISO/TC SIMS General
intensity scale in single ion counting 201/SC6
time-of-flight mass analysers
Vibrational
ISO TS 14101:2012 Surface ISO/TC 229 FTIR Gold
characterization of gold nanoparticles for nanoparticles
nanomaterial specific toxicity screening:
FT-IR method
CEN TS 17010:2016 Guidance on CEN/TC FTIR, Nano-objects
measurands for characterizing nano- 352 Raman, etc.
objects and materials that contain them

Standards on nanocellulose have started to be developed, with standards published or

under preparation in terminology (ISO/TS 20477:2017), overview of characterization
methods (ISO/TR 19716:2016), crystallinity of cellulose by powder X-ray diffraction
(DTS 23361), characterization of individualized cellulose nanofibril samples (TS
21346), and size distribution of cellulose nanocrystals (TS 23151). A series of standards
on magnetic nanomaterials are also likely to develop following the publication of Part 1 of
TS19807 on Magnetic nanosuspensions—Characteristics and measurements of magnetic
nanomaterials. TS 19807-2 on nanostructured superparamagnetic beads for PG
14 nucleic acid extraction—Specification of characteristics and measurements is being
developed.
Standards for graphene and other two-dimensional materials are now being written
in several of the standardization bodies including ISO, IEC, and ASTM. In IEC/TC 113,
for example, there are five standards being written on measuring sheet resistance.
 International standards in nanotechnologies 525

Fig. 2 Graphene standards published or under preparation in ISO/TC 229.

In ISO/TC 229, the standards are split into larger, detailed standards for characterizing
CVD sheet graphene and for those characterizing graphene flakes in powder or liquid
dispersion form and terminology and overview measurement standards. These standards
are currently under development and are outlined in Fig. 2.

Summary
The nanotechnology community requires standards to enable valid and repeatable results
to meet industrial demands. There is an urgent need for standard analytical methods for
nanomaterials to address the stipulations of current and future regulations. Standards are
important in all areas, including a common and accessible terminology, those for specific
measurement methods, those for specific nanomaterials and measurement standards to
underpin health, safety, and environment standards. Standards exist or are in develop-
ment for many of the techniques outlined in other chapters of this book, although gaps
do still exist. Measurement standards should be validated via international interlaboratory
studies. All of these lead to valid, reproducible measurement and characterization in
nanotechnologies.

References
[1] M. Baker, Nature 533 (2016) 452, https://doi.org/10.1038/533452a.
[2] M. Sene, I. Gilmore, J.T. Janssen, Nature 547 (7664) (2017) 397–399, https://doi.org/10.1038/547397a.
[3] ISO/IEC Guide 21-1:2005, 3.1.