Cleanrooms and associated controlled environments - Part 9: Assessment of surface cleanliness for particle concentration (ISO 14644-9:2022)

2020-11-18 (data): Minor revision.

Reinräume und zugehörige Reinraumbereiche - Teil 9: Klassifizierung der partikulären Oberflächenreinheit (ISO 14644-9:2022)

Dieses Dokument beschreibt ein Verfahren für die Bewertung der partikulären Reinheitsgrade auf festen Oberflächen für Anwendungen in Reinräumen und zugehörigen Reinraumbereichen. Empfehlungen zu Prüf- und Messverfahren sowie Angaben zu Oberflächenkenngrößen sind in Anhang A bis Anhang D enthalten.
Dieses Dokument gilt für alle festen Oberflächen in Reinräumen und zugehörigen Reinraumbereichen, wie z. B. Wände, Decken, Fußböden, Arbeitsbereiche, Werkzeuge, Ausrüstungsgegenstände und Produkte. Das Verfahren für die Bewertung der partikulären Oberflächenreinheit (en: surface cleanliness by particle concentration, SCP) ist auf Partikel mit einer Größe zwischen 0,05 µm und 500 µm begrenzt.
Die folgenden Punkte werden in diesem Dokument nicht behandelt:
- Anforderungen an die Reinheit und Eignung von Oberflächen für bestimmte Prozesse;
- Verfahrensweisen für die Reinigung von Oberflächen;
- Materialkenngrößen;
- Bezüge auf die wechselseitigen Bindungskräfte oder Entstehungsprozesse, die üblicherweise zeitabhängig und prozessabhängig sind;
- Auswahl und Anwendung statistischer Bewertungs- und Prüfverfahren;
- weitere Kenngrößen von Partikeln, wie z. B. elektrostatische Ladung, Ionenladungen und mikrobiologischer Zustand.

Salles propres et environnements maîtrisés apparentés - Partie 9: Évaluation de la propreté des surfaces en fonction de la concentration de particules (ISO 14644-9:2022)

Le présent document établit un mode opératoire pour l’évaluation des niveaux de propreté particulaire des surfaces solides, applicables aux salles propres et aux environnements maîtrisés apparentés. Les Annexes A à D fournissent des recommandations relatives aux essais et aux méthodes de mesurage, ainsi que des informations sur les caractéristiques des surfaces.
Le présent document s’applique à toutes les surfaces solides dans les salles propres et environnements maîtrisés apparentés telles que les murs, les plafonds, les sols, les environnements de travail, les outils, les équipements et les produits. Le mode opératoire d’évaluation de la propreté des surfaces par la concentration de particules (SCP) se limite à des tailles de particules comprises entre 0,05 µm et 500 µm.
Le présent document n’aborde pas les points suivants:
—    les exigences pour la propreté et l’adéquation des surfaces à des processus spécifiques;
—    les modes opératoires de nettoyage des surfaces;
—    les caractéristiques des matériaux;
—    les références aux forces de liaison ou aux processus de génération qui sont généralement fonction du temps et qui dépendent du procédé;
—    le choix et l’utilisation de méthodes statistiques pour l’évaluation et les essais;
—    d’autres caractéristiques des particules, telles que la charge électrostatique, les charges ioniques et l’état microbiologique.

Čiste sobe in podobna nadzorovana okolja - 9. del: Ocenjevanje čistosti površine na osnovi koncentracije delcev (ISO 14644-9:2022)

General Information

Status
Published
Public Enquiry End Date
06-Mar-2022
Publication Date
19-Jun-2022
Technical Committee
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
01-Jun-2022
Due Date
06-Aug-2022
Completion Date
20-Jun-2022

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SLOVENSKI STANDARD
SIST EN ISO 14644-9:2022
01-julij-2022
Nadomešča:
SIST EN ISO 14644-9:2012
Čiste sobe in podobna nadzorovana okolja - 9. del: Ocenjevanje čistosti površine
na osnovi koncentracije delcev (ISO 14644-9:2022)

Cleanrooms and associated controlled environments - Part 9: Assessment of surface

cleanliness for particle concentration (ISO 14644-9:2022)

Reinräume und zugehörige Reinraumbereiche - Teil 9: Klassifizierung der partikulären

Oberflächenreinheit (ISO 14644-9:2022)

Salles propres et environnements maîtrisés apparentés - Partie 9: Évaluation de la

propreté des surfaces en fonction de la concentration de particules (ISO 14644-9:2022)

Ta slovenski standard je istoveten z: EN ISO 14644-9:2022
ICS:
13.040.35 Brezprašni prostori in Cleanrooms and associated
povezana nadzorovana controlled environments
okolja
SIST EN ISO 14644-9:2022 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 14644-9:2022
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SIST EN ISO 14644-9:2022
EN ISO 14644-9
EUROPEAN STANDARD
NORME EUROPÉENNE
May 2022
EUROPÄISCHE NORM
ICS 13.040.35 Supersedes EN ISO 14644-9:2012
English Version
Cleanrooms and associated controlled environments - Part
9: Assessment of surface cleanliness for particle
concentration (ISO 14644-9:2022)

Salles propres et environnements maîtrisés apparentés Reinräume und zugehörige Reinraumbereiche - Teil 9:

- Partie 9: Évaluation de la propreté des surfaces en Klassifizierung der partikulären Oberflächenreinheit

fonction de la concentration de particules (ISO 14644- (ISO 14644-9:2022)
9:2022)
This European Standard was approved by CEN on 18 April 2022.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this

European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references

concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN

member.

This European Standard exists in three official versions (English, French, German). A version in any other language made by

translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management

Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,

Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,

Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and

United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels

© 2022 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 14644-9:2022 E

worldwide for CEN national Members.
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SIST EN ISO 14644-9:2022
EN ISO 14644-9:2022 (E)
Contents Page

European foreword ....................................................................................................................................................... 3

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SIST EN ISO 14644-9:2022
EN ISO 14644-9:2022 (E)
European foreword

This document (EN ISO 14644-9:2022) has been prepared by Technical Committee ISO/TC 209

"Cleanrooms and associated controlled environments" in collaboration with Technical Committee

CEN/TC 243 “Cleanroom technology” the secretariat of which is held by BSI.

This European Standard shall be given the status of a national standard, either by publication of an

identical text or by endorsement, at the latest by November 2022, and conflicting national standards

shall be withdrawn at the latest by November 2022.

Attention is drawn to the possibility that some of the elements of this document may be the subject of

patent rights. CEN shall not be held responsible for identifying any or all such patent rights.

This document supersedes EN ISO 14644-9:2012.

Any feedback and questions on this document should be directed to the users’ national standards

body/national committee. A complete listing of these bodies can be found on the CEN website.

According to the CEN-CENELEC Internal Regulations, the national standards organizations of the

following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,

Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,

Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of

North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the

United Kingdom.
Endorsement notice

The text of ISO 14644-9:2022 has been approved by CEN as EN ISO 14644-9:2022 without any

modification.
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SIST EN ISO 14644-9:2022
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SIST EN ISO 14644-9:2022
INTERNATIONAL ISO
STANDARD 14644-9
Second edition
2022-05
Cleanrooms and associated controlled
environments —
Part 9:
Assessment of surface cleanliness for
particle concentration
Salles propres et environnements maîtrisés apparentés —
Partie 9: Évaluation de la propreté des surfaces en fonction de la
concentration de particules
Reference number
ISO 14644-9:2022(E)
© ISO 2022
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SIST EN ISO 14644-9:2022
ISO 14644-9:2022(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2022

All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may

be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on

the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below

or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
© ISO 2022 – All rights reserved
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SIST EN ISO 14644-9:2022
ISO 14644-9:2022(E)
Contents Page

Foreword ........................................................................................................................................................................................................................................iv

Introduction .................................................................................................................................................................................................................................v

1 Scope ................................................................................................................................................................................................................................. 1

2 Normative references ..................................................................................................................................................................................... 1

3 Terms and definitions .................................................................................................................................................................................... 1

4 Abbreviated terms ............................................................................................................................................................................................. 2

5 The surface cleanliness level assessment system ............................................................................................................ 3

5.1 ISO-SCP grading level format ..................................................................................................................................................... 3

5.2 Designation ................................................................................................................................................................................................ 6

5.3 General information on surface cleanliness levels of particle concentration ................................ 6

6 Demonstration of conformity ................................................................................................................................................................6

6.1 Principle ....................................................................................................................................................................................................... 6

6.2 Testing ............................................................................................................................................................................................................ 6

6.3 Test report .................................................................................................................................................................................................. 7

Annex A (informative) Surface characteristics ........................................................................................................................................ 9

Annex B (informative) Descriptor for specific particle size ranges ................................................................................12

Annex C (informative) Parameters influencing the SCP grading level assessments.....................................15

Annex D (informative) Measurement methods for determining surface cleanliness by

particle concentration ................................................................................................................................................................................17

Bibliography .............................................................................................................................................................................................................................26

iii
© ISO 2022 – All rights reserved
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SIST EN ISO 14644-9:2022
ISO 14644-9:2022(E)
Foreword

ISO (the International Organization for Standardization) is a worldwide federation of national standards

bodies (ISO member bodies). The work of preparing International Standards is normally carried out

through ISO technical committees. Each member body interested in a subject for which a technical

committee has been established has the right to be represented on that committee. International

organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.

ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of

electrotechnical standardization.

The procedures used to develop this document and those intended for its further maintenance are

described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the

different types of ISO documents should be noted. This document was drafted in accordance with the

editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).

Attention is drawn to the possibility that some of the elements of this document may be the subject of

patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of

any patent rights identified during the development of the document will be in the Introduction and/or

on the ISO list of patent declarations received (see www.iso.org/patents).

Any trade name used in this document is information given for the convenience of users and does not

constitute an endorsement.

For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and

expressions related to conformity assessment, as well as information about ISO's adherence to

the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see

www.iso.org/iso/foreword.html.

This document was prepared by Technical Committee ISO/TC 209, Cleanrooms and associated controlled

environments, in collaboration with the European Committee for Standardization (CEN) Technical

Committee CEN/TC 243, Cleanroom technology, in accordance with the Agreement on technical

cooperation between ISO and CEN (Vienna Agreement).

This second edition cancels and replaces the first edition (ISO 14644-9:2012), of which it constitutes a

minor revision. The changes are as follows:

— "Class" (classification, classified) has been changed to grade or assessment where appropriate;

— ISO 14644-6 has been removed from the opening text of Clause 3 and, as a result, Clause 2;

— entry 3.8 removed from Clause 3;
— ISO 4287 and ISO 4288 replaced by ISO 21920-2 and ISO 21920-3, respectively;
— ISO 16232-2, ISO 16232-3, ISO 16232-4 and ISO 16232-5 replaced by ISO 16232;
— minor editorial changes.
A list of all parts in the ISO 14644 series can be found on the ISO website.

Any feedback or questions on this document should be directed to the user’s national standards body. A

complete listing of these bodies can be found at www.iso.org/members.html.
© ISO 2022 – All rights reserved
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SIST EN ISO 14644-9:2022
ISO 14644-9:2022(E)
Introduction

Cleanrooms and associated controlled environments provide for the control of contamination to levels

appropriate for accomplishing contamination-sensitive activities. Products and processes that benefit

from the control of contamination include those in such industries as aerospace, microelectronics,

optics, nuclear and life sciences (pharmaceuticals, medical devices, food, healthcare).

ISO 14644-1 to ISO 14644-8, ISO 14698-1 and ISO 14698-2 deal exclusively with airborne particle

and chemical contamination. Many factors, besides the assessment of surface cleanliness, should

be considered in the design, specification, operation and control of cleanrooms and other controlled

environments. These factors are covered in some detail in other parts of ISO 14644 and ISO 14698.

This document provides an analytical process for the determination and designation of surface

cleanliness levels based on particle concentration. This document also lists some methods of testing, as

well as procedure(s) for determining the concentration of particles on surfaces.

Where regulatory agencies impose supplementary guidelines or restrictions, appropriate adaptations

of the testing procedures might be required.

NOTE When assessment of surface cleanliness by particle concentration (SCP) at critical control point(s) is

used as an additional cleanliness attribute to classification of air cleanliness by airborne particle concentration

in accordance with ISO 14644-1, then the space can be described as a cleanroom or clean-zone. If SCP is used

alone, then the space is described as a controlled zone.
© ISO 2022 – All rights reserved
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SIST EN ISO 14644-9:2022
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SIST EN ISO 14644-9:2022
INTERNATIONAL STANDARD ISO 14644-9:2022(E)
Cleanrooms and associated controlled environments —
Part 9:
Assessment of surface cleanliness for particle
concentration
1 Scope

This document establishes a procedure for the assessment of particle cleanliness levels on solid surfaces

in cleanrooms and associated controlled environment applications. Recommendations on testing and

measuring methods, as well as information about surface characteristics, are given in Annexes A to D.

This document applies to all solid surfaces in cleanrooms and associated controlled environments, such

as walls, ceilings, floors, working environments, tools, equipment and products. The procedure for the

assessment of surface cleanliness by particle concentration (SCP) is limited to particles of between

0,05 µm and 500 µm.
The following issues are not considered in this document:

— requirements for the cleanliness and suitability of surfaces for specific processes;

— procedures for the cleaning of surfaces;
— material characteristics;

— references to interactive bonding forces or generation processes that are usually time-dependent

and process-dependent;
— selection and use of statistical methods for assessment and testing;

— other characteristics of particles, such as electrostatic charge, ionic charges and microbiological

state.
2 Normative references
There are no normative references in this document.
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.

ISO and IEC maintain terminology databases for use in standardization at the following addresses:

— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
© ISO 2022 – All rights reserved
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SIST EN ISO 14644-9:2022
ISO 14644-9:2022(E)
3.1
descriptor for specific particle size ranges

differential descriptor that expresses surface cleanliness by particle concentration (SCP) level within

specific particle size ranges

Note 1 to entry: The descriptor may be applied to particle size ranges of special interest or those particle size

ranges that are outside the range of the grading system and specified independently or as a supplement to the

SCP levels.
3.2
direct measurement method
assessment of the contamination without any intermediate steps
3.3
indirect measurement method
assessment of the contamination with intermediate steps
3.4
solid surface
boundary between the solid and a second phase
3.5
surface particle

solid and/or liquid matter adhered and discretely distributed on a surface of interest, excluding film-

like matter that covers the whole surface

Note 1 to entry: Surface particles are adhered via chemical and/or physical interactions.

3.6
surface cleanliness by particle concentration
SCP
condition of a surface with respect to its particle concentration

Note 1 to entry: The surface cleanliness depends upon material and design characteristics, stress loads

(complexity of loads acting on a surface) and prevailing environmental conditions, along with other factors.

3.7
surface cleanliness by particle concentration level
SCP rating

grading number stating the maximum allowable surface concentration, in particles per square metre,

for a considered size of particles [surface cleanliness by particle concentration (SCP) grades 1 to 8],

where level 1 represents the cleanest level
3.8
surface particle concentration
number of individual particles per unit of surface area under consideration
4 Abbreviated terms
For the purposes of this document, the following abbreviated terms apply.
AFM atomic force microscopy
CNC condensation nucleus counter
EDX energy dispersive X-ray spectroscopy
ESCA electron spectroscopy for chemical analysis
ESD electrostatic discharge
© ISO 2022 – All rights reserved
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SIST EN ISO 14644-9:2022
ISO 14644-9:2022(E)
IR infrared (absorption spectroscopy)
OPC optical particle counter
PET polyethylene terephthalate
SCP surface cleanliness by particle concentration
SEM scanning electron microscopy
UV ultraviolet (spectroscopy)
WDX wavelength-dispersive X-ray spectroscopy
5 The surface cleanliness level assessment system
5.1 ISO-SCP grading level format

The degree of SCP in a cleanroom or associated controlled environment shall be designated by a

cleanliness level grading number, N, specifying the maximum total particle concentration on surfaces

permitted for a considered particle size. N shall be determined from Formula (1) with the maximum

permitted total particle concentration on the surface, C , in particles per square metre of surface,

SCP;D
for each considered particle size, D:
Ck= (1)
SCP;D
where

C is the maximum permitted total surface concentration, in particles per square metre of

SCP;D

surface, of particles that are equal to or larger than the considered particle size; C is

SCP;D

rounded to the nearest whole number, using no more than three significant figures;

N is the SCP cleanliness level grading number, which is limited to SCP grade level 1 to SCP

grade level 8; the SCP grade level number N is qualified by the measured particle diameter

D, in micrometres;

NOTE N refers to the exponent base 10 for the concentration of particles at the reference

particle size of 1 µm.
D is the considered particle size, in micrometres;
k is a constant 1, in micrometres.

NOTE 1 The SCP grade level based on the particle concentration can be a time- and process-dependent value

due to the dynamic characteristics of particle generation and transportation.

NOTE 2 Due to the complexity of statistical evaluations and readily available additional references, the

selection and use of statistical methods for testing are not described in this document.

The concentration C , as derived from Formula (1), shall serve as the definitive value. Table 1

SCP;D

presents selected SCP grading levels and corresponding maximum cumulative permitted total surface

concentrations for considered particle sizes.

Figure 1 provides a representation of the selected surface particle grade levels in graphical form.

© ISO 2022 – All rights reserved
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SIST EN ISO 14644-9:2022
ISO 14644-9:2022(E)

Table 1 — Selected SCP grading levels for cleanrooms and associated controlled environments

Units in particles per square metre
Particle size
SCP level
≥ 0,05 µm ≥ 0,1 µm ≥ 0,5 µm ≥ 1 µm ≥ 5 µm ≥ 10 µm ≥ 50 µm ≥ 100 µm ≥ 500 µm
SCP level 1 (200) 100 20 (10)
SCP level 2 (2 000) 1 000 200 100 (20) (10)
SCP level 3 (20 000) 10 000 2 000 1 000 (200) (100)
SCP level 4 (200 000) 100 000 20 000 10 000 2 000 1 000 (200) (100)
SCP level 5 1 000 000 200 000 100 000 20 000 10 000 2 000 1 000 (200)
SCP level 6 (10 000 000) 2 000 000 1 000 000 200 000 100 000 20 000 10 000 2 000
SCP level 7 10 000 000 2 000 000 1 000 000 200 000 100 000 20 000
SCP level 8 10 000 000 2 000 000 1 000 000 200 000

The values in Table 1 are concentrations of particles of the related particle size and SCP level per surface area of one square metre

(1 m ) equal to or larger than the considered particle size (C ).
SCP;D

For figures in parentheses, the corresponding particle sizes should not be used for level determination purposes; select another

particle size for more accurate determination.

The minimum area for testing should be statistically representative of the surface under consideration.

NOTE Assessment of the lower SCP levels requires numerous measurements to establish a significant value.

© ISO 2022 – All rights reserved
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SIST EN ISO 14644-9:2022
ISO 14644-9:2022(E)
Key
X considered particle size, D (µm)
Y particle concentration on a surface ≥ D, C (particles/m )
SCP;D
1 SCP grade level 1
2 SCP grade level 2
3 SCP grade level 3
4 SCP grade level 4
5 SCP grade level 5
6 SCP grade level 6
7 SCP grade level 7
8 SCP grade level 8

The solid lines shown on the graph shall be used for level assessment purposes. The dashed lines should not be used

for level assessment purposes.

NOTE Particle distribution on surfaces typically is not a normal distribution, but is affected by different

factors, such as roughness, porosity, electrostatic charge and deposition mechanisms (see Annex A).

2 5

EXAMPLE SCP grade level 5 (1 µm) signifies that 1 m of surface may carry a maximum of 10 particles with

a considered particle size ≥ 1 µm (D = 1). SCP grade level 5 (10 µm) signifies that 1 m of surface may carry a

maximum of 10 particles per square metre with a considered particle size ≥ 10 µm (D = 10). Any other measured

particle size (D = x) which leads to a concentration that lies below the relevant SCP line is within the specification

of SCP grade level 5 (x µm).
Figure 1 — SCP grade levels

For particle sizes outside the limits of the level numbering system and in cases where only a narrow

particle range or individual particle sizes are of interest, a descriptor can be used (see Annex B).

© ISO 2022 – All rights reserved
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SIST EN ISO 14644-9:2022
ISO 14644-9:2022(E)
5.2 Designation

The SCP grade level number shall be formatted as follows: SCP grade level N (D µm).

The designation of the SCP grade for cleanrooms and associated controlled environments shall also

include the following:
a) the surface type measured;
b) the surface area measured;
c) the measurement method applied.

Details of measurement methods applied, including sampling techniques and measurement devices,

should be retrieved from test reports.

The considered particle size should be determined by agreement between the customer and supplier.

The SCP grade level shall be stated in relation to the measured particle size diameter.

EXAMPLE 1 SCP grade level 2 (0,1 µm); wafer or glass substrate, surface area: 310 cm ; surface particle

counter.

EXAMPLE 2 SCP grade level 5 (0,5 μm); inner wall of a bottle, surface area: 200 cm ; liquid dispersion — liquid

particle counter.
5.3 General information on surface cleanliness levels of particle concentration

Airborne particle concentration and surface particle concentration are generally related. The

relationship is dependent on many factors, such as airflow turbulence, rate of deposition, time of

deposition, deposition velocity, concentration within the air and surface characteristics such as

electrostatic charge (see A.2.4).

To determine SCP, various parameters (see Annex C) and surface characteristics (see Annex A) that

influence testing should be taken into account.
6 Demonstration of conformity
6.1 Principle

Conformity with SCP grade cleanliness level requirements, as specified by the customer, is verified by

performing tests and by providing documentation of the results and conditions of the testing.

Details for demonstrating conformity (see 6.3) shall be agreed upon between the customer and supplier

in advance of testing.
6.2 Testing

Tests performed to demonstrate conformity shall be conducted in a controlled environment using

suitable test methods and calibrated instruments, whenever possible.

Direct and indirect test methods can be used for demonstrating conformity and are given in Annex D.

The list of typical methods described is not exhaustive. Alternative methods of comparable accuracy

may be specified by agreement.

NOTE Measurement by different methods, even when correctly applied, can produce different results of

equal validity.
Repeated measurements are recommended.

The test method and environment shall be agreed upon between the customer and supplier.

© ISO 2022 – All rights reserved
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SIST EN ISO 14644-9:2022
ISO 14644-9:2022(E)

Precautions should be taken to reduce electrostatic charge around the test zone, since electrostatic

charge enhances particle deposition onto surfaces. If the surface is neither conductive, nor grounded

or charge-neutralized, electrostatic charges can occur (see Annex A). Therefore, test results can vary.

6.3 Test report

The results from testing each surface shall be recorded and submitted as a comprehensive report, along

with a statement of conformity or non-conformity with the specified SCP grade levels.

The test report shall include as a minimum the following:
a) basic data:
— date and time of testing;
— name and address of the testing organization;
— name of testing personnel;
b) references consulted:
— standards;
— guidelines;
— regulations;
— number and year of publication of this document, i.e. ISO 14644-9:2022;
c) environmental data:

— environmental conditions for sampling (i.e. temperature, humidity, cleanliness);

— environmental conditions for measurement (i.e. temperature, humidity, cleanliness) (not

essential for use with direct methods);
— location (e.g. room) used for the measurements;
d) specimen:
— clear identification of the test object;
— description of the test object;
— graph and/or sketch of the test specimen;
e) test setup:
— photo and/or sketch of the test setup;
— description of operating parameters;
— description of measurement points;
— description of hardware used in the test setup;
f) measurement devices:

— identification of the instrument(s) and measuring devices used and current calibration

certificate(s);
— measurement range of measuring devices used;
— reference of calibration certificates;
© ISO 2022 – All rights reserved
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SIST EN ISO 14644-9:2022
ISO 14644-9:2022(E)
g) performing the test:

— relevant details of the test procedure used, with any available data describing deviations from

the test procedure (if agreed);

— surface condition before sampling (e.g. after cleaning, after packaging, under atmospheric or

vacuum conditions);
— specified test and measurement procedure or method;
— occupancy state(s) during sampling and measurement;
— specified test method(s);

— all agreed documentation (e.g. raw data, background particle concentrations, pictures, graphs,

cleaning and packaging);

— duration, location and position of sampling (not essential for use with direct methods);

— duration, location
...

SLOVENSKI STANDARD
oSIST prEN ISO 14644-9:2022
01-februar-2022
Čiste sobe in podobna nadzorovana okolja - 9. del: Ocenjevanje čistosti površine
na osnovi koncentracije delcev (ISO/FDIS 14644-9:2021)

Cleanrooms and associated controlled environments - Part 9: Assessment of surface

cleanliness for particle concentration (ISO/FDIS 14644-9:2021)

Reinräume und zugehörige Reinraumbereiche - Teil 9: Klassifizierung der partikulären

Oberflächenreinheit (ISO/FDIS 14644-9:2021)

Salles propres et environnements maîtrisés apparentés - Partie 9: Évaluation de la

propreté des surfaces en fonction de la concentration de particules (ISO/FDIS 14644-

9:2021)
Ta slovenski standard je istoveten z: prEN ISO 14644-9
ICS:
13.040.35 Brezprašni prostori in Cleanrooms and associated
povezana nadzorovana controlled environments
okolja
oSIST prEN ISO 14644-9:2022 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN ISO 14644-9:2022
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oSIST prEN ISO 14644-9:2022
FINAL
INTERNATIONAL ISO/FDIS
DRAFT
STANDARD 14644-9
ISO/TC 209
Cleanrooms and associated controlled
Secretariat: ANSI
environments —
Voting begins on:
2021-12-14
Part 9:
Voting terminates on:
Assessment of surface cleanliness for
2022-03-08
particle concentration
ISO/CEN PARALLEL PROCESSING
RECIPIENTS OF THIS DRAFT ARE INVITED TO
SUBMIT, WITH THEIR COMMENTS, NOTIFICATION
OF ANY RELEVANT PATENT RIGHTS OF WHICH
THEY ARE AWARE AND TO PROVIDE SUPPOR TING
DOCUMENTATION.
IN ADDITION TO THEIR EVALUATION AS
Reference number
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO-
ISO/FDIS 14644-9:2021(E)
LOGICAL, COMMERCIAL AND USER PURPOSES,
DRAFT INTERNATIONAL STANDARDS MAY ON
OCCASION HAVE TO BE CONSIDERED IN THE
LIGHT OF THEIR POTENTIAL TO BECOME STAN-
DARDS TO WHICH REFERENCE MAY BE MADE IN
NATIONAL REGULATIONS. © ISO 2021
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oSIST prEN ISO 14644-9:2022
ISO/FDIS 14644-9:2021(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2021

All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may

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Published in Switzerland
© ISO 2021 – All rights reserved
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oSIST prEN ISO 14644-9:2022
ISO/FDIS 14644-9:2021(E)
Contents Page

Foreword ........................................................................................................................................................................................................................................iv

Introduction .................................................................................................................................................................................................................................v

1 Scope ................................................................................................................................................................................................................................. 1

2 Normative references ..................................................................................................................................................................................... 1

3 Terms and definitions .................................................................................................................................................................................... 1

4 Abbreviated terms ............................................................................................................................................................................................. 2

5 The surface cleanliness level assessment system ............................................................................................................ 3

5.1 ISO-SCP grading level format ..................................................................................................................................................... 3

5.2 Designation ................................................................................................................................................................................................ 6

5.3 General information on surface cleanliness levels of particle concentration ................................ 6

6 Demonstration of conformity ................................................................................................................................................................6

6.1 Principle ....................................................................................................................................................................................................... 6

6.2 Testing ............................................................................................................................................................................................................ 6

6.3 Test report .................................................................................................................................................................................................. 7

Annex A (informative) Surface characteristics ........................................................................................................................................ 9

Annex B (informative) Descriptor for specific particle size ranges ................................................................................12

Annex C (informative) Parameters influencing the SCP grading level assessments.....................................15

Annex D (informative) Measurement methods for determining surface cleanliness by

particle concentration ................................................................................................................................................................................17

Bibliography .............................................................................................................................................................................................................................26

iii
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oSIST prEN ISO 14644-9:2022
ISO/FDIS 14644-9:2021(E)
Foreword

ISO (the International Organization for Standardization) is a worldwide federation of national standards

bodies (ISO member bodies). The work of preparing International Standards is normally carried out

through ISO technical committees. Each member body interested in a subject for which a technical

committee has been established has the right to be represented on that committee. International

organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.

ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of

electrotechnical standardization.

The procedures used to develop this document and those intended for its further maintenance are

described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the

different types of ISO documents should be noted. This document was drafted in accordance with the

editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).

Attention is drawn to the possibility that some of the elements of this document may be the subject of

patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of

any patent rights identified during the development of the document will be in the Introduction and/or

on the ISO list of patent declarations received (see www.iso.org/patents).

Any trade name used in this document is information given for the convenience of users and does not

constitute an endorsement.

For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and

expressions related to conformity assessment, as well as information about ISO's adherence to

the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see

www.iso.org/iso/foreword.html.

This document was prepared by Technical Committee ISO/TC 209, Cleanrooms and associated controlled

environments, in collaboration with the European Committee for Standardization (CEN) Technical

Committee CEN/TC 243, Cleanroom technology, in accordance with the Agreement on technical

cooperation between ISO and CEN (Vienna Agreement).

This second edition cancels and replaces the first edition (ISO 14644-9:2012), of which it constitutes a

minor revision. The changes are as follows:

— "Class" (classification, classified) has been changed to grade or assessment where appropriate;

— ISO 14644-6 has been removed from the opening text of Clause 3 and, as a result, Clause 2;

— entry 3.8 removed from Clause 3;
— minor editorial changes.
A list of all parts in the ISO 14644 series can be found on the ISO website.

Any feedback or questions on this document should be directed to the user’s national standards body. A

complete listing of these bodies can be found at www.iso.org/members.html.
© ISO 2021 – All rights reserved
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oSIST prEN ISO 14644-9:2022
ISO/FDIS 14644-9:2021(E)
Introduction

Cleanrooms and associated controlled environments provide for the control of contamination to levels

appropriate for accomplishing contamination-sensitive activities. Products and processes that benefit

from the control of contamination include those in such industries as aerospace, microelectronics,

optics, nuclear and life sciences (pharmaceuticals, medical devices, food, healthcare).

ISO 14644-1 to ISO 14644-8, ISO 14698-1 and ISO 14698-2 deal exclusively with airborne particle

and chemical contamination. Many factors, besides the assessment of surface cleanliness, should

be considered in the design, specification, operation and control of cleanrooms and other controlled

environments. These factors are covered in some detail in other parts of ISO 14644 and ISO 14698.

This document provides an analytical process for the determination and designation of surface

cleanliness levels based on particle concentration. This document also lists some methods of testing, as

well as procedure(s) for determining the concentration of particles on surfaces.

Where regulatory agencies impose supplementary guidelines or restrictions, appropriate adaptations

of the testing procedures might be required.

NOTE When assessment of surface cleanliness by particle concentration (SCP) at critical control point(s) is

used as an additional cleanliness attribute to classification of air cleanliness by airborne particle concentration

in accordance with ISO 14644-1, then the space can be described as a cleanroom or clean-zone. If SCP is used

alone, then the space is described as a controlled zone.
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oSIST prEN ISO 14644-9:2022
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oSIST prEN ISO 14644-9:2022
FINAL DRAFT INTERNATIONAL STANDARD ISO/FDIS 14644-9:2021(E)
Cleanrooms and associated controlled environments —
Part 9:
Assessment of surface cleanliness for particle
concentration
1 Scope

This document establishes a procedure for the assessment of particle cleanliness levels on solid surfaces

in cleanrooms and associated controlled environment applications. Recommendations on testing and

measuring methods, as well as information about surface characteristics, are given in Annexes A to D.

This document applies to all solid surfaces in cleanrooms and associated controlled environments, such

as walls, ceilings, floors, working environments, tools, equipment and products. The procedure for the

assessment of surface cleanliness by particle concentration (SCP) is limited to particles of between

0,05 µm and 500 µm.
The following issues are not considered in this document:

— requirements for the cleanliness and suitability of surfaces for specific processes;

— procedures for the cleaning of surfaces;
— material characteristics;

— references to interactive bonding forces or generation processes that are usually time-dependent

and process-dependent;
— selection and use of statistical methods for assessment and testing;

— other characteristics of particles, such as electrostatic charge, ionic charges and microbiological

state.
2 Normative references
There are no normative references in this document.
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.

ISO and IEC maintain terminology databases for use in standardization at the following addresses:

— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
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ISO/FDIS 14644-9:2021(E)
3.1
descriptor for specific particle size ranges

differential descriptor that expresses surface cleanliness by particle concentration (SCP) level within

specific particle size ranges

Note 1 to entry: The descriptor may be applied to particle size ranges of special interest or those particle size

ranges that are outside the range of the grading system and specified independently or as a supplement to the

SCP levels.
3.2
direct measurement method
assessment of the contamination without any intermediate steps
3.3
indirect measurement method
assessment of the contamination with intermediate steps
3.4
solid surface
boundary between the solid and a second phase
3.5
surface particle

solid and/or liquid matter adhered and discretely distributed on a surface of interest, excluding film-

like matter that covers the whole surface

Note 1 to entry: Surface particles are adhered via chemical and/or physical interactions.

3.6
surface cleanliness by particle concentration
SCP
condition of a surface with respect to its particle concentration

Note 1 to entry: The surface cleanliness depends upon material and design characteristics, stress loads

(complexity of loads acting on a surface) and prevailing environmental conditions, along with other factors.

3.7
surface cleanliness by particle concentration level
SCP rating

grading number stating the maximum allowable surface concentration, in particles per square metre,

for a considered size of particles [surface cleanliness by particle concentration (SCP) grades 1 to 8],

where level 1 represents the cleanest level
3.8
surface particle concentration
number of individual particles per unit of surface area under consideration
4 Abbreviated terms
For the purposes of this document, the following abbreviated terms apply.
AFM atomic force microscopy
CNC condensation nucleus counter
EDX energy dispersive X-ray spectroscopy
ESCA electron spectroscopy for chemical analysis
ESD electrostatic discharge
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oSIST prEN ISO 14644-9:2022
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IR infrared (absorption spectroscopy)
OPC optical particle counter
PET polyethylene terephthalate
SCP surface cleanliness by particle concentration
SEM scanning electron microscopy
UV ultraviolet (spectroscopy)
WDX wavelength-dispersive X-ray spectroscopy
5 The surface cleanliness level assessment system
5.1 ISO-SCP grading level format

The degree of SCP in a cleanroom or associated controlled environment shall be designated by a

cleanliness level grading number, N, specifying the maximum total particle concentration on surfaces

permitted for a considered particle size. N shall be determined from Formula (1) with the maximum

permitted total particle concentration on the surface, C , in particles per square metre of surface,

SCP;D
for each considered particle size, D:
Ck= (1)
SCP;D
where

C is the maximum permitted total surface concentration, in particles per square metre of

SCP;D

surface, of particles that are equal to or larger than the considered particle size; C is

SCP;D

rounded to the nearest whole number, using no more than three significant figures;

N is the SCP cleanliness level grading number, which is limited to SCP grade level 1 to SCP

grade level 8; the SCP grade level number N is qualified by the measured particle diameter

D, in micrometres;

NOTE N refers to the exponent base 10 for the concentration of particles at the reference

particle size of 1 µm.
D is the considered particle size, in micrometres;
k is a constant 1, in micrometres.

NOTE 1 The SCP grade level based on the particle concentration can be a time- and process-dependent value

due to the dynamic characteristics of particle generation and transportation.

NOTE 2 Due to the complexity of statistical evaluations and readily available additional references, the

selection and use of statistical methods for testing are not described in this document.

The concentration C , as derived from Formula (1), shall serve as the definitive value. Table 1

SCP;D

presents selected SCP grading levels and corresponding maximum cumulative permitted total surface

concentrations for considered particle sizes.

Figure 1 provides a representation of the selected surface particle grade levels in graphical form.

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oSIST prEN ISO 14644-9:2022
ISO/FDIS 14644-9:2021(E)

Table 1 — Selected SCP grading levels for cleanrooms and associated controlled environments

Units in particles per square metre
Particle size
SCP level
≥ 0,05 µm ≥ 0,1 µm ≥ 0,5 µm ≥ 1 µm ≥ 5 µm ≥ 10 µm ≥ 50 µm ≥ 100 µm ≥ 500 µm
SCP level 1 (200) 100 20 (10)
SCP level 2 (2 000) 1 000 200 100 (20) (10)
SCP level 3 (20 000) 10 000 2 000 1 000 (200) (100)
SCP level 4 (200 000) 100 000 20 000 10 000 2 000 1 000 (200) (100)
SCP level 5 1 000 000 200 000 100 000 20 000 10 000 2 000 1 000 (200)
SCP level6 (10 000 000) 2 000 000 1 000 000 200 000 100 000 20 000 10 000 2 000
SCP level 7 10 000 000 2 000 000 1 000 000 200 000 100 000 20 000
SCP level 8 10 000 000 2 000 000 1 000 000 200 000

The values in Table 1 are concentrations of particles of the related particle size and SCP level per surface area of one square metre

(1 m ) equal to or larger than the considered particle size (C ).
SCP;D

For figures in parentheses, the corresponding particle sizes should not be used for level determination purposes; select another

particle size for more accurate determination.

The minimum area for testing should be statistically representative of the surface under consideration.

NOTE Assessment of the lower SCP levels requires numerous measurements to establish a significant value.

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oSIST prEN ISO 14644-9:2022
ISO/FDIS 14644-9:2021(E)
Key
X considered particle size, D (µm)
Y particle concentration on a surface ≥ D, C (particles/m )
SCP;D
1 SCP grade level 1
2 SCP grade level 2
3 SCP grade level 3
4 SCP grade level 4
5 SCP grade level 5
6 SCP grade level 6
7 SCP grade level 7
8 SCP grade level 8

The solid lines shown on the graph shall be used for level assessment purposes. The dashed lines should not be used

for level assessment purposes.

NOTE Particle distribution on surfaces typically is not a normal distribution, but is affected by different

factors, such as roughness, porosity, electrostatic charge and deposition mechanisms (see Annex A).

2 5

EXAMPLE SCP grade level 5 (1 µm) signifies that 1 m of surface may carry a maximum of 10 particles with

a considered particle size ≥ 1 µm (D = 1). SCP grade level 5 (10 µm) signifies that 1 m of surface may carry a

maximum of 10 particles per square metre with a considered particle size ≥ 10 µm (D = 10). Any other measured

particle size (D = x) which leads to a concentration that lies below the relevant SCP line is within the specification

of SCP grade level 5 (x µm).
Figure 1 — SCP grade levels

For particle sizes outside the limits of the level numbering system and in cases where only a narrow

particle range or individual particle sizes are of interest, a descriptor can be used (see Annex B).

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5.2 Designation

The SCP grade level number shall be formatted as follows: SCP grade level N (D µm).

The designation of the SCP grade for cleanrooms and associated controlled environments shall also

include the following:
a) the surface type measured;
b) the surface area measured;
c) the measurement method applied.

Details of measurement methods applied, including sampling techniques and measurement devices,

should be retrieved from test reports.

The considered particle size should be determined by agreement between the customer and supplier.

The SCP grade level shall be stated in relation to the measured particle size diameter.

EXAMPLE 1 SCP grade level 2 (0,1 µm); wafer or glass substrate, surface area: 310 cm ; surface particle

counter.

EXAMPLE 2 SCP grade level 5 (0,5 μm); inner wall of a bottle, surface area: 200 cm ; liquid dispersion — liquid

particle counter.
5.3 General information on surface cleanliness levels of particle concentration

Airborne particle concentration and surface particle concentration are generally related. The

relationship is dependent on many factors, such as airflow turbulence, rate of deposition, time of

deposition, deposition velocity, concentration within the air and surface characteristics such as

electrostatic charge (see A.2.4).

To determine SCP, various parameters (see Annex C) and surface characteristics (see Annex A) that

influence testing should be taken into account.
6 Demonstration of conformity
6.1 Principle

Conformity with SCP grade cleanliness level requirements, as specified by the customer, is verified by

performing tests and by providing documentation of the results and conditions of the testing.

Details for demonstrating conformity (see 6.3) shall be agreed upon between the customer and supplier

in advance of testing.
6.2 Testing

Tests performed to demonstrate conformity shall be conducted in a controlled environment using

suitable test methods and calibrated instruments, whenever possible.

Direct and indirect test methods can be used for demonstrating conformity and are given in Annex D.

The list of typical methods described is not exhaustive. Alternative methods of comparable accuracy

may be specified by agreement.

NOTE Measurement by different methods, even when correctly applied, can produce different results of

equal validity.
Repeated measurements are recommended.

The test method and environment shall be agreed upon between the customer and supplier.

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oSIST prEN ISO 14644-9:2022
ISO/FDIS 14644-9:2021(E)

Precautions should be taken to reduce electrostatic charge around the test zone, since electrostatic

charge enhances particle deposition onto surfaces. If the surface is neither conductive, nor grounded

or charge-neutralized, electrostatic charges can occur (see Annex A). Therefore, test results can vary.

6.3 Test report

The results from testing each surface shall be recorded and submitted as a comprehensive report, along

with a statement of conformity or non-conformity with the specified SCP grade levels.

The test report shall include as a minimum the following:
a) basic data:
— date and time of testing;
— name and address of the testing organization;
— name of testing personnel;
b) references consulted:
— standards;
— guidelines;
— regulations;
— number and year of publication of this document, i.e. ISO 14644-9:—;
c) environmental data:

— environmental conditions for sampling (i.e. temperature, humidity, cleanliness);

— environmental conditions for measurement (i.e. temperature, humidity, cleanliness) (not

essential for use with direct methods);
— location (e.g. room) used for the measurements;
d) specimen:
— clear identification of the test object;
— description of the test object;
— graph and/or sketch of the test specimen;
e) test setup:
— photo and/or sketch of the test setup;
— description of operating parameters;
— description of measurement points;
— description of hardware used in the test setup;
f) measurement devices:

— identification of the instrument(s) and measuring devices used and current calibration

certificate(s);
— measurement range of measuring devices used;
— reference of calibration certificates;
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g) performing the test:

— relevant details of the test procedure used, with any available data describing deviations from

the test procedure (if agreed);

— surface condition before sampling (e.g. after cleaning, after packaging, under atmospheric or

vacuum conditions);
— specified test and measurement procedure or method;
— occupancy state(s) during sampling and measurement;
— specified test method(s);

— all agreed documentation (e.g. raw data, background particle concentrations, pictures, graphs,

cleaning and packaging);

— duration, location and position of sampling (not essential for use with direct methods);

— duration, location and position of measurement (not essential for use with direct methods);

— noticeable observations made during sampling or measurement, where applicable;
— number of measurements performed;

— clear identification of the position and the area of the surface measured and specific designations

for coordinates of the surface, if applicable;
h) results and analysis:

— visual inspection of the test surface before and after measurement, where applicable;

— measurement values and/or their analysis;
— statement of data quality;
— particle size ranges considered;

— test results, including particle concentration data for given particle sizes, for all tests performed;

— SCP grading level with designation expressed as SCP cleanliness grade level N;

— acceptance criteria for the clean surface, if agreed between the customer and the supplier.

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oSIST prEN ISO 14644-9:2022
ISO/FDIS 14644-9:2021(E)
Annex A
(informative)
Surface characteristics
A.1 Surface description

A surface is commonly characterized by its texture (such as roughness, porosity), its mechanical

properties (such as hardness) and its physicochemical properties (such as electrostatic surface charge

and surface tension). Each of these properties should be considered before selecting a test method for

the surface cleanliness assessment, or as an aid for the interpretation of the test results.

A.2 Surface characteristics
A.2.1 Roughness
A.2.1.1 Description

As the roughness of a surface affects many of its physical properties, surface roughness is not easily

described by one single parameter, nor is it an intrinsic property of the surface. Roughness exists in

two principal planes: at right angles to the surface, where it may be characterized by height, and in the

plane of the surface, identified as “texture” and characterized by waviness. The roughness of a surface

can be determined by mechanical or optical methods.
A.2.1.2 Testing

A frequently used mechanical method for the determination of roughness is the stylus instrument (see,

for example, ISO 4287 or ISO 4288).

Frequently used optical methods for the determination of roughness and porous texture are

microscopes (optical, confocal, interferometry, with or without tunnel effect, taper sectioning).

A.2.2 Porosity
A.2.2.1 Definition and description

Porosity is a measure of the void spaces in a material and is expressed as a decimal between 0 and 1, or

as a percentage between 0 % and 100 %.

— Effective porosity (also called open porosity) refers to the fraction of the total volume in which

fluid flow is effectively taking place (this excludes dead-end pores or non-connected cavities).

— Macroporosity refers to pores equal to or greater than 50 nm in diameter. Fluid flow through

macropores is described by bulk diffusion.

— Mesoporosity refers to pores equal to or greater than 2 nm but less than 50 nm in diameter.

— Microporosity refers to pores smaller than 2 nm in diameter. Movement in micropores is by

activated diffusion.
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A.2.2.2 Testing

There are several ways to estimate the porosity of a given material or mixture of materials, which is

called material matrix.

The volume/density method is fast and highly accurate (normally within ± 2 % of the actual porosity).

The volume and the weight of the material are measured. The weight of the material divided by the

density of the material gives the volume that the material takes up, minus the pore volume. Therefore,

the pore volume is simply equal to the total volume minus the material volume, i.e. (pore volume) = (total

volume) − (material volume).
The water saturation method is slightly more difficult but is
...

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