Air intake filter systems for rotary machinery - Test methods - Part 1: Static filter elements (ISO 29461-1:2013)

This International Standard describes a procedure of measuring the performance of general ventilation air cleaning devices in their end use installed configuration. The performance measurements include removal efficiency by particle size and the resistance to airflow. The procedures for test include the definition and reporting of the system airflow. The procedure describes a method of counting ambient air particles of 0,3 μm to 5,0 μm upstream and downstream of the in-place air cleaner(s) in a functioning air handling system. The procedure describes the reduction of particle counter data to calculate removal efficiency by particle size. Since filter installations vary dramatically in design and shape, a protocol for evaluating the suitability of a site for filter evaluation and for system evaluation is included. When the evaluated site conditions meet the minimum criteria established for system evaluation, the performance evaluation of the system can also be performed according to this procedure. This international standard for testing also describes performance specifications for the testing equipment and defines procedures for calculating and reporting the results. This standard is not intended for measuring performance of portable or movable room air cleaners or for evaluation of filter installations with and expected filtration efficiency at or above 99% or at or below 30% when measured at 0,4 μm.

Prüfmethoden für Luftfiltereinlasssysteme von Rotationsmaschinen und stationäre Verbrennungsmaschinen - Teil 1: Testmethoden und Klassifizierung von statischen Filterelementen (ISO 29461-1:2013)

In ISO 29461 werden Prüfverfahren für die Ermittlung der Leistung von Partikelluftfiltern und
-filtereinlasssysteme festgelegt, die Rotationsmaschinen, z. B. stationäre Gasturbinen, Kompressoren und andere stationäre Verbrennungskraftmaschinen. Die Norm gilt für Luftfilter mit einem Anfangswirkungsgrad bis 99,9 % bei Partikelgrößen von 0,4 µm. Filter mit höheren Wirkungsgraden werden nach anderen Normen (z. B. EN 1822) geprüft und klassifiziert.  Diese Verfahren sind vorgesehen für Filter, die bei Volumenströmen im Bereich von 0,25 m3/s (900 m3/h) bis zu 1,67 m3/s (6000 m3/h) betrieben werden.
Der vorliegende Teil der ISO 29461 bezieht sich auf statische Filtersysteme (Sperrfilter), kann aber, wenn zutreffend, unter bestimmten Umständen auch auf andere Filterarten und  systeme angewendet werden.
In diesem Normteil der ISO 29461 werden zwei Verfahren zur Bestimmung des Wirkungsgrades angewendet:
   Messung des Partikelwirkungsgrads (unter Bezug auf Partikelanzahl und  größe);
   Messung des gravimetrischen Wirkungs  oder Abscheidegrads (gewichteter Massenanteil des abgeschiedenen Beladungsstaubes).
Um Aussagen über die Wirksamkeit des Abbaus elektrostatischer Ladungen zu ermöglichen, muss eine Probe aus einem planen Filtermedium oder aus einem Filtermedienpaket eines identischen Filters konditio¬niert (elektrostatisch entladen) werden.
Nach Bestimmung des Anfangswirkungsgrads des unbehandelten Filters wird bis zum Erreichen der Enddruckdifferenz stufenweise Staub auf das Filter aufgegeben. Daraus sind dann Angaben über einen bestaubten Filter zu bestimmen.
Die nach diesem Teil der ISO 29461 Norm für die Leistung ermittelten Ergebnisse können nicht unmittelbar zur quantitativen Vorhersage der Leistung bezogen auf Wirkungsgrad und Lebensdauer für den jeweiligen Anwendungsfall des Filters verwendet werden. Andere Faktoren, die sich auf die Leistung auswirken und berücksichtigt werden müssen, werden in den Anhängen beschrieben.

Systèmes de filtration d'air d'admission pour machines tournantes - Méthodes d'essai - Partie 1: Éléments filtrants pour filtres statiques (ISO 29461-1:2013)

L'ISO 29461 spécifie les méthodes et modes opératoires pour la détermination de la performance des filtres à air utilisés dans les systèmes de filtration d'air d'admission pour machines tournantes, telles que les turbines à gaz, les compresseurs et les moteurs fixes à combustion interne. Elle s'applique aux filtres à air dont l'efficacité initiale va jusqu'à 99,9 % pour les particules de 0,4 µm. Les filtres avec une efficacité initiale supérieure sont soumis à essai et classés conformément à d'autres normes (par exemple l'EN 1822). Ce mode opératoire est prévu pour les filtres fonctionnant à des débits compris dans la plage de 0,25 m3/s (900 m3/h) à 1,67 m3/s (6 000 m3/h).
L'ISO 29461-1:2013 concerne les systèmes de filtration (barrières filtrantes) statiques, mais peut aussi s'appliquer à d'autres types de filtres et systèmes de filtration, le cas échéant.
Deux méthodes de détermination de l'efficacité sont utilisées dans l'ISO 29461-1:2013:
l'efficacité particulaire (efficacité mesurée par rapport au nombre et à la taille des particules);
l'efficacité gravimétrique (élimination en masse pondérée de la poussière de chargement).
De plus, un échantillon de média plan ou un bloc d'échantillon de média, prélevé sur un filtre identique, doit être conditionné (déchargé) afin d'obtenir des informations sur l'intensité du mécanisme d'élimination électrostatique.
Après détermination de son efficacité initiale, le filtre non traité est progressivement chargé de poussière jusqu'à atteindre sa perte de charge finale d'essai. Des informations sur les performances du filtre chargé sont ainsi obtenues.
Les données de performance obtenues conformément à l'ISO 29461-1:2013 ne peuvent être utilisées quantitativement (par elles-mêmes) pour prédire les performances en service en termes d'efficacité et de durée de vie. Les autres facteurs ayant une incidence sur les performances à prendre en compte sont décrits dans les annexes.

Zračni filtrski sistemi rotacijskih strojev - Preskusne metode - 1. del: Statični filtrski elementi (ISO 29461-1:2013)

ISO 29461 določa metode in postopke za ugotavljanje delovanja zračnih filtrov za delce, ki se uporabljajo v filtrirnih sistemih z dovodom zraka za rotacijske stroje, kot so nepremične plinske turbine, kompresorji in drugi nepremični motorji z notranjim izgorevanjem. Velja za zračne filtre, katerih začetna učinkovitost v zvezi z delci velikosti 0,4 μm je do 99,9 %. Filtri z višjimi začetnimi učinkovitostmi se preskusijo in razvrstijo v skladu z drugimi standardi (npr. EN 1822). Ti postopki so namenjeni za filtre, ki delujejo na pretokih znotraj razpona od 0,25 m3/s (900 m3/h) do 1,67 m3/s (6000 m3/h). Ta del standarda ISO 29461 se nanaša na statične (pregradne) filtrirne sisteme, vendar ga je v ustreznih okoliščinah mogoče uporabiti za druge tipe filtrov in filtrirne sisteme. V tem delu standarda ISO 29461 se uporabljata dve metodi za ugotavljanje učinkovitosti: – učinkovitost delcev (izmerjena glede na število in velikost delcev); – gravimetrična učinkovitost (odstotek ovrednotene odstranitve mase prahu). Poleg tega se obdela (izprazni) vzorec medija traku ali vzorec paketa medija iz identičnega filtra, s čimer se zagotovijo informacije o intenzivnosti mehanizma elektrostatičnega odstranjevanja. V neobdelan filter se po ugotovitvi začetne učinkovitosti v zvezi z delci postopoma nalaga prah, dokler se ne doseže končni padec tlaka v preskusu. Pridobijo se informacije o učinkovitosti filtra pod obremenitvijo. Rezultatov glede zmogljivosti, pridobljenih v skladu s tem delom standarda ISO 29461, ni mogoče samih po sebi kvantitativno uporabiti za predvidevanje zmogljivosti med obratovanjem, v zvezi z učinkovitostjo in življenjsko dobo. Drugi dejavniki, ki vplivajo na zmogljivost in ki jih je treba upoštevati, so opisani v dodatkih.

General Information

Status
Withdrawn
Public Enquiry End Date
24-Dec-2010
Publication Date
25-Jul-2013
Withdrawal Date
13-Oct-2021
Technical Committee
Current Stage
9900 - Withdrawal (Adopted Project)
Start Date
14-Oct-2021
Due Date
06-Nov-2021
Completion Date
14-Oct-2021

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SLOVENSKI STANDARD
SIST EN ISO 29461-1:2013
01-september-2013

=UDþQLILOWUVNLVLVWHPLURWDFLMVNLKVWURMHY3UHVNXVQHPHWRGHGHO6WDWLþQL

ILOWUVNLHOHPHQWL ,62

Air intake filter systems for rotary machinery - Test methods - Part 1: Static filter

elements (ISO 29461-1:2013)
Prüfmethoden für Luftfiltereinlasssysteme von Rotationsmaschinen und stationäre
Verbrennungsmaschinen - Teil 1: Testmethoden und Klassifizierung von statischen
Filterelementen (ISO 29461-1:2013)

Systèmes de filtration d'air d'admission pour machines tournantes - Méthodes d'essai -

Partie 1: Éléments filtrants pour filtres statiques (ISO 29461-1:2013)
Ta slovenski standard je istoveten z: EN ISO 29461-1:2013
ICS:
29.160.99 Drugi standardi v zvezi z Other standards related to
rotacijskimi stroji rotating machinery
SIST EN ISO 29461-1:2013 en,fr

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

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SIST EN ISO 29461-1:2013
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SIST EN ISO 29461-1:2013
EUROPEAN STANDARD
EN ISO 29461-1
NORME EUROPÉENNE
EUROPÄISCHE NORM
April 2013
ICS 29.160.99
English Version
Air intake filter systems for rotary machinery - Test methods -
Part 1: Static filter elements (ISO 29461-1:2013)

Systèmes de filtration d'air d'admission pour machines Luftfiltereinlasssysteme von Rotationsmaschinen -

tournantes - Méthodes d'essai - Partie 1: Éléments filtrants Prüfverfahren - Teil 1: Statische Filterelemente (ISO 29461-

pour filtres statiques (ISO 29461-1:2013) 1:2013)
This European Standard was approved by CEN on 1 March 2013.

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, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,

Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United

Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: Avenue Marnix 17, B-1000 Brussels

© 2013 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 29461-1:2013: E

worldwide for CEN national Members.
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SIST EN ISO 29461-1:2013
EN ISO 29461-1:2013 (E)
Contents Page

Foreword ..............................................................................................................................................................3

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SIST EN ISO 29461-1:2013
EN ISO 29461-1:2013 (E)
Foreword

This document (EN ISO 29461-1:2012) has been prepared by Technical Committee ISO/TC 142 "Cleaning

equipment for air and other gases" in collaboration with Technical Committee CEN/TC 195 “Air filters for

general air cleaning” the secretariat of which is held by UNI.

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 October 2013, and conflicting national standards shall be withdrawn at

the latest by October 2013.

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

rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.

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, Former Yugoslav Republic of Macedonia, France, Germany, Greece,

Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,

Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom.

Endorsement notice

The text of ISO 29461-1:2013 has been approved by CEN as EN ISO 29461-1:2013 without any modification.

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SIST EN ISO 29461-1:2013
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SIST EN ISO 29461-1:2013
INTERNATIONAL ISO
STANDARD 29461-1
First edition
2013-04-01
Air intake filter systems for rotary
machinery — Test methods —
Part 1:
Static filter elements
Systèmes de filtration d’air d’admission pour machines tournantes —
Méthodes d’essai —
Partie 1: Éléments filtrants pour filtres statiques
Reference number
ISO 29461-1:2013(E)
ISO 2013
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SIST EN ISO 29461-1:2013
ISO 29461-1:2013(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2013

All rights reserved. Unless otherwise specified, 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
Case postale 56 • CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail copyright@iso.org
Web www.iso.org
Published in Switzerland
ii © ISO 2013 – All rights reserved
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SIST EN ISO 29461-1:2013
ISO 29461-1:2013(E)
Contents Page

Foreword ..........................................................................................................................................................................................................................................v

0 Introduction .............................................................................................................................................................................................................vi

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

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

3 Terms and definitions ..................................................................................................................................................................................... 2

3.2 Velocity........................................................................................................................................................................................................... 2

3.3 Efficiency ...................................................................................................................................................................................................... 2

3.5 Pressure drop (differential pressure) ................................................................................................................................. 3

3.6 Filter area .................................................................................................................................................................................................... 3

3.7 Filters .............................................................................................................................................................................................................. 3

3.8 Test aerosol ................................................................................................................................................................................................ 4

3.9 Test dust ........................................................................................................................................................................................................ 5

3.10 Particle sampling ................................................................................................................................................................................... 5

3.11 Particle shedding ................................................................................................................................................................................... 5

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

5 General requirements ..................................................................................................................................................................................... 8

6 Test rig and equipment .................................................................................................................................................................................. 8

6.1 Test condition ........................................................................................................................................................................................... 8

6.2 Test rig ............................................................................................................................................................................................................ 8

6.3 DEHS test aerosol generation ..................................................................................................................................................12

6.4 Aerosol sampling system ............................................................................................................................................................13

6.5 Flow measurement ...........................................................................................................................................................................14

6.6 Particle counter ...................................................................................................................................................................................14

6.7 Differential pressure measuring equipment ..............................................................................................................15

6.8 Dust feeder ..............................................................................................................................................................................................15

6.9 Diluter equipment .............................................................................................................................................................................17

7 Qualification of test rig and apparatus .......................................................................................................................................18

7.1 General ........................................................................................................................................................................................................18

7.2 Air velocity uniformity in the test duct ...........................................................................................................................18

7.3 Aerosol uniformity in the test duct.....................................................................................................................................19

7.4 Particle counter sizing accuracy ...........................................................................................................................................20

7.5 Particle counter zero test ............................................................................................................................................................20

7.6 Particle counter overload test .................................................................................................................................................20

7.7 100 % efficiency test .......................................................................................................................................................................21

7.8 Zero % efficiency test .....................................................................................................................................................................21

7.9 Aerosol generator response time .........................................................................................................................................21

7.10 Dilution ratio ..........................................................................................................................................................................................22

7.11 Correlation ratio .................................................................................................................................................................................22

7.12 Pressure drop checking ................................................................................................................................................................23

7.13 Dust feeder airflow rate ...............................................................................................................................................................23

7.14 Reference filter check .....................................................................................................................................................................24

7.15 Summary of qualification requirements ........................................................................................................................25

7.16 Apparatus maintenance ...............................................................................................................................................................25

8 Test materials .......................................................................................................................................................................................................26

8.1 Test air .........................................................................................................................................................................................................26

8.2 Test aerosol .............................................................................................................................................................................................26

8.3 Loading dust ...........................................................................................................................................................................................27

8.4 Final filter .................................................................................................................................................................................................27

9 Test procedure .....................................................................................................................................................................................................27

9.1 Preparation of filter to be tested...........................................................................................................................................28

9.2 Initial pressure drop .......................................................................................................................................................................28

© ISO 2013 – All rights reserved iii
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SIST EN ISO 29461-1:2013
ISO 29461-1:2013(E)

9.3 Initial particulate efficiency measurement..................................................................................................................28

9.4 Conditioning test ................................................................................................................................................................................32

9.5 Dust loading ............................................................................................................................................................................................32

10 Uncertainty calculation of the test results ..............................................................................................................................33

10.1 Particulate efficiency for medium efficiency filters (initial particulate efficiency:

35 ≤ E ≤ 85 % at 0,4 μm)..............................................................................................................................................................33

10.2 Particulate efficiency for high efficiency filters (initial particulate efficiency >85 % at

0,4 μm) ........................................................................................................................................................................................................34

10.3 Gravimetric efficiency ....................................................................................................................................................................36

11 Reporting ...................................................................................................................................................................................................................36

11.1 General ........................................................................................................................................................................................................36

11.2 Interpretation of test reports ..................................................................................................................................................37

11.3 Summary ...................................................................................................................................................................................................38

11.4 Efficiency ...................................................................................................................................................................................................40

11.5 Pressure drop and airflow rate ..............................................................................................................................................40

11.6 Marking ......................................................................................................................................................................................................40

Annex A (normative) Conditioning test procedure ............................................................................................................................47

Annex B (informative) Shedding from filter elements ....................................................................................................................51

Annex C (informative) Commentary ..................................................................................................................................................................53

Annex D (normative) Pressure drop calculation ..................................................................................................................................57

Annex E (normative) Net Area Calculation .................................................................................................................................................59

Bibliography .............................................................................................................................................................................................................................66

iv © ISO 2013 – All rights reserved
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SIST EN ISO 29461-1:2013
ISO 29461-1:2013(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.

International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.

The main task of technical committees is to prepare International Standards. Draft International

Standards adopted by the technical committees are circulated to the member bodies for voting.

Publication as an International Standard requires approval by at least 75 % of the member bodies

casting a vote.

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.

ISO 29461-1 was prepared by Technical Committee ISO/TC 142, Cleaning equipment for air and other gases.

ISO 29461 consists of the following parts, under the general title Air intake filter systems for rotary

machinery — Test methods:
— Part 1: Static filter elements

Cleanable (pulse jet) and surface loading filters, mechanical integrity of filter elements, in situ testing,

marine and offshore environment filter systems, and cleanable (pulse Jet) filter elements will form the

subjects of future parts.
© ISO 2013 – All rights reserved v
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SIST EN ISO 29461-1:2013
ISO 29461-1:2013(E)
0 Introduction
0.1 Filters in power generating/compressor applications

In rotating machinery applications, the filtering system, typically a set of filter elements arranged in

a suitable manner, are an important part of the whole turbine/compressor system. The development

of turbine machinery used for energy production or others has led to more sophisticated equipment

and therefore the importance of good protection of these systems has become more important in the

recent years. It is known that particulate contamination can deteriorate a turbine power system quite

substantially if not taken care of.

This event is often described as “erosion”, “fouling” and “hot corrosion” where salt and other corrosive

particles are known as potential problems. Other particulate matters may also cause significant

reduction of efficiency of the systems. It is important to understand that air filter devices in such systems

are located in various environmental conditions. The range of climate and particulate contamination is

very wide, ranging from deserts to humid rain forests to arctic environments. The requirements on

these filter systems are obviously different depending on where they will be operating.

ISO 29461 has based the performance of the air intake filter systems not only upon heavy dust collection

but also particulate efficiency in a size range that is considered to be the problematic area for these

applications. Both ultra-fine and fine particles, as well as larger particles, should be considered

when evaluating turbine fouling. In typical outdoor air, ultra-fine and fine particles in the size range

from 0,01 μm to 1 μm contribute to >99 % of the number concentration and to >90 % of the surface

contamination. The majority of the mass normally comes from larger particles (>1,0 μm).

Turbo-machinery filters comprise a wide range of products from filters for very coarse particles to

filters for very fine, sub-micron particles. The range of products varies from self-cleaning to depth and

surface loading systems. The filters and the systems have to withstand a wide temperature and humidity

range, very low to very high dust concentration and mechanical stress. The shape of products existing

today can be of many different types and have different functions such as droplet separators, coalescing

products, filter pads, metal filters, inertial filters, filter cells, bag filters, panel-type, self-cleanable and

depth loading filter cartridges and pleated media surface filter elements.

ISO 29461 will provide a way to compare these products in a similar way and define what criteria are

important for air filter intake systems for rotary machinery performance protection. The performance

of products in this broad range must be compared in a good manner. Comparing different filters and

filter types must be done with respect to the operating conditions they finally will be used in.

For instance, if a filter or a filter system is meant to operate in an extreme, very dusty environment, the

real particulate efficiency of such a filter cannot be predicted because the dust loading of the filter plays

an important role. ISO 29461-2 will address the performance of cleanable and surface loading filters.

0.2 Filtration characteristics

Initiatives to address the potential problems of particle re-entrainment, shedding and the in-service

charge neutralization characteristics of certain types of media have been included in Annexes A and B.

Certain types of filter media rely on electrostatic effects to achieve high efficiencies at low resistance

to airflow. Exposure to some types of challenge, such as combustion particles or other fine particles,

may inhibit such charges with the result that filter performance suffers. The normative test procedure,

described in Annex A, provides techniques for identifying this type of behaviour. This procedure is used to

determine whether the filter particulate efficiency is dependent on the electrostatic removal mechanism

and to provide quantitative information about the importance of the electrostatic removal. The procedure

was selected because it is well established, reproducible, relatively fast and easy to perform.

In an ideal filtration process, each particle would be permanently arrested at the first contact with a

filter fibre, but incoming particles may impact on a captured particle and dislodge it into the air stream.

Fibres or particles from the filter itself could also be released, due to mechanical forces. From the user’s

point of view it might be important to know this, see Annex B.
vi © ISO 2013 – All rights reserved
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SIST EN ISO 29461-1:2013
ISO 29461-1:2013(E)

Filters with a low initial or conditioned particulate efficiency (<35 %) for sub-micron particles (0,4 μm)

that do not increase their efficiency during the operation will typically not provide any major protection

for the operating machinery when challenged with typical atmospheric aerosols where the majority of

particles are smaller than 1,0 μm. However, in some cases with aerosols having a dominant fraction of

coarse particles, filters with low efficiencies at sub-micron particles can serve as a protection for later

filter stages and can also have a higher average particulate efficiency (e.g. surface loading filters) at

0,4 μm due to the dust loading. Therefore a gravimetric test can provide some information about capacity

and gravimetric efficiency for those aerosols. In general, a lower total filtration level than 35 % at 0,4 μm

should not be recommended for an air intake filter system for rotary machinery when the aerosol loading

of the filters are not contributing to a significant increase of the efficiency during the operation.

0.3 Organization of ISO 29461

The methods and procedures for determining particulate efficiency, pressure drop and the corresponding

reporting formats are the same for all types of static filter element.

The test methods concerning particulate efficiency, pressure drop and reported values are the same for all

filters, except for loading characteristics and cleaning procedure, which are different for cleanable surface

loading filters. These filters incorporate cleaning procedures and have different loading characteristics;

therefore, they require appropriately modified test methods, which will be defined in Part 2.

Part 3 will provide methods for determining the mechanical integrity of filters under conditions that

may be encountered in abnormal operating environments.

Part 4 will describe methods of testing installed filters under in-service operating conditions (in situ testing).

Part 5 will cover test methods for the specific requirement of offshore and marine application, and

specify methods for determining the sea salt removal efficiency of individual filters and/or complete

filter systems.

Part 6 will cover test methods for cleanable filter elements, and will not cover the system testing

(e.g. cleaning device) as in Part 2.
This part of ISO 29461 describes the test methods for st
...

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