FprEN ISO 10121-3

Test methods for assessing the performance of gas-phase air cleaning media and devices for general ventilation - Part 3: Classification system for GPACDs applied to treatment of outdoor air (ISO/FDIS 10121-3:2022)

This part of ISO 10121 establishes a classification system for GPACD’s supplying make-up air to
general ventilation systems using outdoor air polluted by local urban sources and/or long-distance
pollution. The classification system is intended to aid in assessing molecular pollution besides the
particulate pollution dealt with by ISO 16890-1.

Methode zur Leistungsermittlung von Medien und Vorrichtungen zur Reinigung der Gasphase für die allgemeine Lüftung - Teil 3: Klassifizierungssystem für die Behandlung von Außenluft (ISO/FDIS 10121-3:2022)

Dieser Teil von ISO 10121 erstellt ein Klassifizierungssystem für GPACD, die Außenluft in einem Durchgang an allgemeine Belüftungssysteme unter Verwendung von durch lokale urbane Quellen und/oder Verschmutzung aus großer Entfernung verschmutzte Außenluft liefern. Zweck des Klassifizierungssystems ist es, die Beurteilung der molekularen Verschmutzung zusätzlich zu der in ISO 16890 1 behandelten Partikelverschmutzung zu unterstützen.
Die gewählten normativen Schmutzstoffe sind Ozon, Schwefeldioxid, Stickstoffdioxid und Toluol aufgrund ihrer Relevanz für den bestimmungsgemäßen Gebrauch. Jedem Schmutzstoff werden drei Beanspruchungsgrade zugewiesen, die den üblichen Leistungsbereich der für die Anwendung vorgesehenen Vorrichtungen wiedergeben. Die Beanspruchungsgrade sind mit der benötigten Leistung verbunden, aber die Verbindung einer spezifischen Beanspruchungsgradanforderung mit einer bestimmten Orts- oder Stadtgröße liegt außerhalb des Anwendungsbereichs dieser Klassifizierung. Der zu behandelnde Luftströmungstyp ist Außenluft zu Gebäuden, d. h. eine Filtration von einem riesigen Außenluftempfänger mit gekannten, relativ stabilen Konzentrationen, auch wenn die Konzentration täglich und jährlich variieren kann, und/oder lokal erhöhten Konzentrationen aufgrund von Hauptverkehrsstraßen. Die Prüfung erfolgt nach Abschnitt 5, Abschnitt 6 und ISO 10121 2.
Die Klassifizierung wird als integrierte Reinigungsleistung für den höchsten Beanspruchungsgrad, der der Vorrichtung zugewiesen werden kann, ausgedrückt. Jedem der vier normativen Schmutzstoffe wird eine separate Klasse zugewiesen. Da die Auswahl der normativen Schmutzstoffe und der Beanspruchungsgrade spezifisch ist und nur für den bestimmungsgemäßen Gebrauch gilt, sind alle anderen Anwendungen ausgeschlossen. Insbesondere sind GPACD in Rezirkulationsanwendungen und/oder die Verschmutzung aus Innenraumschmutzstoffen handhaben sowie pharmazeutische, mikroelektronische, nukleare, Heimatschutz- und militärische Anwendungen ausdrücklich ausgeschlossen.

Méthodes d’essai pour l’évaluation de la performance des médias et des dispositifs de filtration moléculaire pour la ventilation générale - Partie 3: Système de classification pour les GPACD appliqués au traitement de l’air extérieur (ISO/FDIS 10121-3:2022)

Preskusna metoda za ocenjevanje zmogljivosti sredstev in naprav za čiščenje plinske faze za splošno prezračevanje - 3. del: Sistem klasifikacije za GPACD, ki se uporablja za obdelavo zraka na prostem (ISO/FDIS 10121-3:2022)

General Information

• Status: Not Published
• ICS: 91.140.30 - Ventilation and air-conditioning systems
• Technical Committee: CEN/TC 195 - Air filters for general air cleaning
• Drafting Committee: CEN/TC 195 - Air filters for general air cleaning
• Ref Project: kSIST FprEN ISO 10121-3:2022 - Test methods for assessing the performance of gas-phase air cleaning media and devices for general ventilation - Part 3: Classification system for GPACDs applied to treatment of outdoor air (ISO/FDIS 10121-3:2022)

Standards Content (sample)

SLOVENSKI STANDARD
oSIST prEN ISO 10121-3:2021
01-julij-2021
Preskusna metoda za ocenjevanje zmogljivosti sredstev in naprav za čiščenje

plinske faze za splošno prezračevanje - 3. del: Sistem klasifikacije za GPACD, ki se

uporablja za obdelavo zraka na prostem (ISO/DIS 10121-3:2021)
Test methods for assessing the performance of gas-phase air cleaning media and

devices for general ventilation - Part 3: Classification system for GPACDs applied to

treatment of outdoor air (ISO/DIS 10121-3:2021)
Methode zur Leistungsermittlung von Medien und Vorrichtungen zur Reinigung der

Gasphase für die allgemeine Lüftung - Teil 3: Klassifizierungssystem für die Behandlung

von Außenluft (ISO/DIS 10121-3:2021)

Méthodes d’essai pour l’évaluation de la performance des médias et des dispositifs de

filtration moléculaire pour la ventilation générale - Partie 3: Système de classification

pour les GPACD appliqués au traitement de l’air extérieur (ISO/DIS 10121-3:2021)
Ta slovenski standard je istoveten z: prEN ISO 10121-3
ICS:
91.140.30 Prezračevalni in klimatski Ventilation and air-
sistemi conditioning systems
oSIST prEN ISO 10121-3:2021 en,fr,de

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

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oSIST prEN ISO 10121-3:2021
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oSIST prEN ISO 10121-3:2021
DRAFT INTERNATIONAL STANDARD
ISO/DIS 10121-3
ISO/TC 142 Secretariat: UNI
Voting begins on: Voting terminates on:
2021-05-05 2021-07-28
Test methods for assessing the performance of gas-phase
air cleaning media and devices for general ventilation —
Part 3:
Classification system for GPACDs applied to treatment of
outdoor air
ICS: 91.140.30
THIS DOCUMENT IS A DRAFT CIRCULATED
This document is circulated as received from the committee secretariat.
FOR COMMENT AND APPROVAL. IT IS
THEREFORE SUBJECT TO CHANGE AND MAY
NOT BE REFERRED TO AS AN INTERNATIONAL
STANDARD UNTIL PUBLISHED AS SUCH.
IN ADDITION TO THEIR EVALUATION AS
ISO/CEN PARALLEL PROCESSING
BEING ACCEPTABLE FOR INDUSTRIAL,
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
STANDARDS MAY ON OCCASION HAVE TO
BE CONSIDERED IN THE LIGHT OF THEIR
POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
Reference number
NATIONAL REGULATIONS.
ISO/DIS 10121-3:2021(E)
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 SUPPORTING DOCUMENTATION. ISO 2021
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oSIST prEN ISO 10121-3:2021
ISO/DIS 10121-3:2021(E)
ISO/DIS 10121-3:2021(E)
Contents

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

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

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

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

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

4 Symbols and abbreviated terms ............................................................................................................. 6

4.1 Symbols............................................................................................................................................................ 6

4.2 Abbreviated terms ....................................................................................................................................... 7

5 Classification system for outdoor air .................................................................................................... 7

5.1 General ............................................................................................................................................................. 7

5.2 Test setup and normative test parameters ........................................................................................ 7

5.3 Initial removal efficiency .......................................................................................................................... 8

5.4 Dose concept .................................................................................................................................................. 8

5.5 Classes, duty levels & dose ........................................................................................................................ 9

5.6 Normative pollutants and concentrations .......................................................................................... 9

5.7 Integrated removal efficiency .............................................................................................................. 10

5.8 Classification example graph ................................................................................................................ 10

5.9 Desorption and retentivity .................................................................................................................... 12

6 Classification test sequence .................................................................................................................. 12

6.1 General .......................................................................................................................................................... 12

6.2 Conditioning ............................................................................................................................................... 12

6.3 Initial removal efficiency ....................................................................................................................... 12

6.4 Capacity determination expressed as E [%] vs D [g/m ] ......................................................... 13

C N

6.4.1 Zero to LD .............................................................................................................................................. 13

6.4.2 Check E at LD ....................................................................................................................................... 13

6.4.3 LD to MD ................................................................................................................................................. 13

6.4.4 MD to HD and HD ................................................................................................................................ 13

6.5 Retentivity ................................................................................................................................................... 13

6.6 Premature Stop .......................................................................................................................................... 13

7 Classification system ............................................................................................................................... 14

7.1 General .......................................................................................................................................................... 14

7.2 Reporting of the LD, MD and HD dose values .................................................................................. 14

7.3 Classification example ............................................................................................................................ 14

8 Report ........................................................................................................................................................... 16

8.1 General .......................................................................................................................................................... 16

8.2 Test report layout ..................................................................................................................................... 16

Annex A (informative) Information about environment pollutant concentration .................. 21

COPYRIGHT PROTECTED DOCUMENT

A.1 Pollutant concentration in outdoor air ............................................................................................. 21

© ISO 2021

Bibliography ....................................................................................................................................................... 23

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.
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ii © ISO 2021 – All rights reserved
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oSIST prEN ISO 10121-3:2021
ISO/DIS 10121-3:2021(E)
Contents

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

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

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

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

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

4 Symbols and abbreviated terms ............................................................................................................. 6

4.1 Symbols............................................................................................................................................................ 6

4.2 Abbreviated terms ....................................................................................................................................... 7

5 Classification system for outdoor air .................................................................................................... 7

5.1 General ............................................................................................................................................................. 7

5.2 Test setup and normative test parameters ........................................................................................ 7

5.3 Initial removal efficiency .......................................................................................................................... 8

5.4 Dose concept .................................................................................................................................................. 8

5.5 Classes, duty levels & dose ........................................................................................................................ 9

5.6 Normative pollutants and concentrations .......................................................................................... 9

5.7 Integrated removal efficiency .............................................................................................................. 10

5.8 Classification example graph ................................................................................................................ 10

5.9 Desorption and retentivity .................................................................................................................... 12

6 Classification test sequence .................................................................................................................. 12

6.1 General .......................................................................................................................................................... 12

6.2 Conditioning ............................................................................................................................................... 12

6.3 Initial removal efficiency ....................................................................................................................... 12

6.4 Capacity determination expressed as E [%] vs D [g/m ] ......................................................... 13

C N

6.4.1 Zero to LD .............................................................................................................................................. 13

6.4.2 Check E at LD ....................................................................................................................................... 13

6.4.3 LD to MD ................................................................................................................................................. 13

6.4.4 MD to HD and HD ................................................................................................................................ 13

6.5 Retentivity ................................................................................................................................................... 13

6.6 Premature Stop .......................................................................................................................................... 13

7 Classification system ............................................................................................................................... 14

7.1 General .......................................................................................................................................................... 14

7.2 Reporting of the LD, MD and HD dose values .................................................................................. 14

7.3 Classification example ............................................................................................................................ 14

8 Report ........................................................................................................................................................... 16

8.1 General .......................................................................................................................................................... 16

8.2 Test report layout ..................................................................................................................................... 16

Annex A (informative) Information about environment pollutant concentration .................. 21

A.1 Pollutant concentration in outdoor air ............................................................................................. 21

Bibliography ....................................................................................................................................................... 23

© ISO 2021 – All rights reserved iii
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oSIST prEN ISO 10121-3:2021
ISO/DIS 10121-3:2021(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 142, Cleaning equipment for air and other

gases.
A list of all parts in the ISO 10121 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.
iv © ISO 2021 – All rights reserved
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oSIST prEN ISO 10121-3:2021
ISO/DIS 10121-3:2021(E)
Introduction

There is an increasing use and need for gas-phase filtration in general filtration applications. This demand

can be expected to increase rapidly due to the increasing gaseous pollution problems in the world

together with an increasing awareness that solutions to the problems are available in the form of

filtration devices or, phrased more technically, gas-phase air cleaning devices (GPACD). The performance

of devices relies to a large extent on the performance of a gas-phase air cleaning media (GPACM)

incorporated in the device. Still applications and device performance are often poorly understood by the

users and suppliers of such media and devices. Media tests may also be adequate to offer data for real

applications if actual low concentrations (< 100 ppb) and longer exposure times (>weeks) can be used in

the test, provided that the geometrical configuration, packing density and flow conditions of the small-

scale test specimen are equal to those used in the real applications. Such tests are however not included

in the scope of ISO 10121.

ISO 10121 parts 1 and 2 aim to provide laboratory test methods for GPACM and GPACD respectively.

From the tests and reports produced a person skilled in the field of molecular filtration can evaluate the

performance of different products as well as comparing performance by benchmark tests for specific

applications. However, to make these evaluations a basic knowledge in chemistry, molecular filtration

and the application at hand are necessary.

Today, not only persons skilled in molecular filtration face challenges with increasing pollution. Annex A

shows annual average concentration of selected outdoor pollutants, the concentration differences of

different urban and industrial settings as well as an example of ambient air quality guidelines. The air

quality guideline is from Malaysia, but most countries have similar national threshold values. Due to this

increasing pollution in urban areas any building owner, facility management engineer, design engineers

or maintenance personnel needs to be able to evaluate GPACD’s for general ventilation in buildings.

Different standards classifying air filters for particle filtration e.g. ASHRAE 52.2, and ISO 16890 have

together with many national standards made a vast difference in assisting selection of air filters for

particle filtration for general ventilation in buildings. Such standards classifying molecular filtration

devices i.e. GPACD’s have to this date not been available. Part three of this series addresses the specific

case of outdoor air to buildings in cities and aim to be used in parallel with ISO 16890-1.

ISO 10121 consists of three parts:

— ISO 10121-1 covers three different media configurations and is targeted towards giving a standardized

interface between media suppliers and producers of air cleaning devices. It may also be used between

media suppliers and end customers with regards to loose fill media properties.

— ISO 10121-2 aims to give a standardized interface between suppliers of air cleaning devices and end

customers seeking the most cost-efficient way to employ gas-phase filtration.

—ISO 10121-3 provides a classification system for the specific application of GPACD’s to general

ventilation of outdoor air polluted by local urban sources and/or long-distance pollution.

© ISO 2021 – All rights reserved v
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oSIST prEN ISO 10121-3:2021
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oSIST prEN ISO 10121-3:2021
ISO/DIS 10121-3:2021(E)
Test methods for assessing the performance of gas-phase air
cleaning media and devices for general ventilation — Part 3:
Classification system for GPACD’s applied to treatment of make-up
air
1 Scope

This part of ISO 10121 establishes a classification system for GPACDs supplying single pass outdoor air

to general ventilation systems using outdoor air polluted by local urban sources and/or long-distance

pollution. The classification system is intended to aid in assessing molecular pollution in addition to the

particulate pollution dealt with by ISO 16890-1.

The selected normative pollutants are ozone, sulphur dioxide, nitrogen dioxide and toluene due to their

relevance to the intended application. Three duty levels are assigned for each pollutant reflecting the

typical performance range of devices intended for the application. The duty levels are related to the

performance needed, but it is not in the scope of this classification to relate a specific duty level need to a

certain place or city size. The air flow type to be covered is outdoor air to buildings i.e. a one pass filtration

from a vast outdoor recipient of known fairly stable concentrations even if the concentration may have

daily and yearly variations and/or local increased concentrations due to main traffic routes. The testing

is performed according to clause 5, clause 6 and ISO 10121-2.

The classification is expressed as an integrated removal efficiency for the highest duty level that the

device may be awarded. A separate class is given for each of the four normative pollutants. Since selection

of normative pollutants and duty levels are specific and unique to the intended application, all other

applications are excluded. In particular, GPACDs in recirculation applications and/or dealing with

pollution from indoor sources as well as pharmaceutical, microelectronic, nuclear, homeland security and

military applications are specifically excluded.
2 Normative references

The following documents are referred to in the text in such a way that some or all of their content

constitutes requirements of this document. For dated references, only the edition cited applies. For

undated references, the latest edition of the referenced document (including any amendments) applies.

ISO 10121-2, Test methods for assessing the performance of gas-phase air cleaning media and devices for

general ventilation — Part 2: Gas-phase air cleaning devices (GPACD)

ISO 16890-1, Air filters for general ventilation - Part 1: Technical specifications, requirements and

classification system based upon particulate matter efficiency (ePM)
3 Terms and definitions

For the purposes of this document, the terms and definitions given in ISO 29464 and the following apply.

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

— ISO Online browsing platform: available at https://www.iso.org/obp
© ISO 2021 – All rights reserved 1
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oSIST prEN ISO 10121-3:2021
ISO/DIS 10121-3:2021(E)
— IEC Electropedia: available at http://www.electropedia.org/
3.1
adsorption

process in which the molecules of a gas or vapour adhere by physical or chemical processes to the

exposed surface of solid substances, both the outer surface and inner pore surface, with which they come

into contact
[Source: ISO 29464:2017; 3.5.7]
3.2
adsorbate

molecular compound in gaseous or vapour phase that may be retained by an adsorbent (3.3) medium

[Source: ISO 29464:2017; 3.5.3]3.3
adsorbent

material having the ability to retain gaseous or vapour contaminants on its surface by physical or

chemical processes
[Source: ISO 29464:2017; 3.5.3]
3.4
ambient pressure
absolute barometric pressure immediately outside the test rig
[Source: ISO 29464:2017; 3.5.50, modified]
3.5
adsorbate capacity

maximum amount (mass or moles) of a selected adsorbate (3.2) that can be contained in GAPC medium

or device under given test conditions, and a specific end point (termination time)

Note 1 to entry: Capacity can also be negative during desorption (3.11).
[Source: ISO 29464:2017; 3.5.12]
3.6
challenge air stream

test contaminant(s) (3.10) of interest diluted to the specified concentration(s) of the test prior to

filtration
[Source: ISO 29464:2017; 3.5.13]
3.7
challenge concentration

concentration of the test contaminant(s) (3.10) of interest in the air stream prior to filtration (challenge

air stream (3.6))
[Source: ISO 29464:2017; 3.5.14]
3.8
challenge compound

chemical compound that is being used as the contaminant (3.10) of interest for any given test

2 © ISO 2021 – All rights reserved
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oSIST prEN ISO 10121-3:2021
ISO/DIS 10121-3:2021(E)
[Source: ISO 29464:2017; 3.5.15]
3.9
concentration
quantity of one substance dispersed in a defined amount of another
Note 1 to entry: Indices “n” denote location.

[Source: ISO 29464:2017; 3.1.7, modified - Cn and note 1 to entry have been added]

3.10
contaminant

substance (solid, liquid or gas) that negatively affects the intended use of a fluid

[Source: ISO 29464:2017; 3.1.8]
3.11
desorption

process in which adsorbate (3.2) molecules leave the surface of the adsorbent and re-enter the air stream

Note 1 to entry: Desorption is the opposite of adsorption.
[Source: ISO 29464:2017; 3.5.21]
3.12
downstream
area or region into which fluid flows on leaving the GPACD

[Source: ISO 29464:2017; 3.1.11, modified – GPACD is used instead of test device]

3.13
Normative Dose

dose [mass/GPACD face area] that reaches a GPACD calculated from air flow in [volume/time], time,

pollution concentration [mass /volume] and GPACD face area
3.14
efficiency vs. capacity curve

plot of the GPACD removal efficiency (3.30) against the integrated capacity over the duration of a

challenge test for a particular challenge concentration (3.7) and airflow
[Source: ISO 29464:2017; 3.5.22]
3.15
efficiency vs. time curve

plot of the GPACD removal efficiency (3.30) against time over the duration of a challenge test for a

particular challenge concentration (3.7) and airflow
[Source: ISO 29464:2017; 3.5.23]
3.16
face velocity
volumetric air flow rate divided by the nominal GPACD face area
© ISO 2021 – All rights reserved 3
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oSIST prEN ISO 10121-3:2021
ISO/DIS 10121-3:2021(E)
Note 1 to entry: GPACD face velocity is expressed in m/s.

[Source: ISO 29464:2017; 3.1.15, modified – GPACD face area is used instead of filter face area]

3.17
gas

substance whose vapour pressure is greater than the ambient pressure (3.4) at ambient temperature

[Source: ISO 29464:2017; 3.1.28]
3.18
gas-phase air cleaning device
GPACD

assembly of a fixed size enabling the removal of specific gas- or vapour-phase contaminants

Note 1 to entry: It is normally box shaped or fits into a box of dimensions between 290 × 290 × 290 mm

up to approximately 610 × 610 × 610 mm or 2 × 2 × 2 feet.
[Source: ISO 29464:2017; 3.5.32, modified – Note has been modified.]
3.19
GPACD face area
nominal cross-sectional area of the GPACD

Note 1 to entry: For the purpose of standardizing measurements, the nominal area is calculated using

610 x 610 mm for a full size filter, 610 x 305 mm for a half size filter and 305 x 305 mm for a quarter size

filter.
3.20
heavy-duty

corresponds to a removal efficiency versus dose performance for a GPACD that is used in challenging

environments e.g. heavily polluted environments.
3.21
initial efficiency

removal efficiency of an unexposed filter or GPACD calculated as soon as possible after the start of a test

Note 1 to entry: For gas-phase, this should be calculated as soon as a steady reading can be obtained.

3.22
integrated removal efficiency

the numerically integrated fraction or percentage of a challenge contaminant that is removed by a GPACD

over a specified time or dose
...