High-efficiency filters and filter media for removing particles in air - Part 2: Aerosol production, measuring equipment and particle-counting statistics (ISO 29463-2:2011)

ISO 29463-2:2011 specifies the aerosol production and measuring equipment used for testing high-efficiency filters and filter media in accordance with ISO 29463-3, ISO 29463-4 and ISO 29463-5, as well as the statistical basis for particle counting with a small number of counted events. It is intended to be used in conjunction with ISO 29463-1, ISO 29463-3, ISO 29463-4 and ISO 29463-5.

Schwebstofffilter und Filtermedien zur Abscheidung von Partikeln aus der Luft - Teil 2: Aerosolerzeugung, Messgeräte und Partikelzählstatistik (ISO 29463-2:2011)

Dieser Teil der ISO 29463 beschreibt die Aerosolerzeugung und Messgeräte für die Prüfung von Filtern mit hohem Abscheidegrad und Filtermedien in Übereinstimmung mit ISO 29463 3, ISO 29463 4 und ISO 29463 5 sowie die statistische Grundlage für Partikelzählung mit einer kleinen Anzahl von Zählereignissen. Er sollte in Verbindung mit ISO 29463 1, ISO 29463 3, ISO 29463 4 und ISO 29463 5 verwendet werden.

Filtres à haut rendement et filtres pour l'élimination des particules dans l'air - Partie 2: Production d'aérosol, équipement de mesure et statistique de comptage de particules (ISO 29463-2:2011)

La présente partie de l'ISO 29463 spécifie la production d'aérosol et l'équipement de mesure utilisé pour soumettre à essai des filtres à haut rendement et des médias filtrants conformément à l'ISO 29463‑3, à l'ISO 29463‑4 et à l'ISO 29463‑5, ainsi que les bases statistiques des comptages de particules sur un nombre limité d'événements dénombrés. Elle est destinée à être utilisée conjointement avec l'ISO 29463‑1, l'ISO 29463‑3, l'ISO 29463‑4 et l'ISO 29463‑5.

Zelo učinkoviti filtri in filtrirno sredstvo za odstranjevanje delcev iz zraka - 2. del: Proizvodnja aerosola, merilna oprema in statistika štetja delcev (ISO 29463-2:2011)

ISO 29463-2:2011 določa proizvodnjo aerosola in merilno opremo za preskušanje zelo učinkovitih filtrov in filtrirnega sredstva v skladu s standardi ISO 29463-3, ISO 29463-4 in ISO 29463-5 ter statistično podlago za štetje delcev z majhnim številom štetih dogodkov. Predviden je za uporabo v povezavi s standardi ISO 29463-1, ISO 29463-3, ISO 29463-4 in ISO 29463-5.

General Information

Status
Published
Publication Date
09-Oct-2018
Current Stage
6060 - Definitive text made available (DAV) - Publishing
Due Date
10-Oct-2018
Completion Date
10-Oct-2018

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SIST EN ISO 29463-2:2018
01-december-2018
1DGRPHãþD
SIST EN 1822-2:2010

=HORXþLQNRYLWLILOWULLQILOWULUQRVUHGVWYR]DRGVWUDQMHYDQMHGHOFHYL]]UDNDGHO

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High-efficiency filters and filter media for removing particles in air - Part 2: Aerosol

production, measuring equipment and particle-counting statistics (ISO 29463-2:2011)

Schwebstofffilter und Filtermedien zur Abscheidung von Partikeln aus der Luft - Teil 2:

Aerosolerzeugung, Messgeräte und Partikelzählstatistik (ISO 29463-2:2011)

Filtres à haut rendement et filtres pour l'élimination des particules dans l'air - Partie 2:

Production d'aérosol, équipement de mesure et statistique de comptage de particules

(ISO 29463-2:2011)
Ta slovenski standard je istoveten z: EN ISO 29463-2:2018
ICS:
13.040.99 Drugi standardi v zvezi s Other standards related to air
kakovostjo zraka quality
91.140.30 3UH]UDþHYDOQLLQNOLPDWVNL Ventilation and air-
VLVWHPL conditioning systems
SIST EN ISO 29463-2:2018 en,fr,de

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

---------------------- Page: 1 ----------------------
SIST EN ISO 29463-2:2018
---------------------- Page: 2 ----------------------
SIST EN ISO 29463-2:2018
EN ISO 29463-2
EUROPEAN STANDARD
NORME EUROPÉENNE
October 2018
EUROPÄISCHE NORM
ICS 91.140.30 Supersedes EN 1822-2:2009
English Version
High-efficiency filters and filter media for removing
particles in air - Part 2: Aerosol production, measuring
equipment and particle-counting statistics (ISO 29463-
2:2011)

Filtres à haut rendement et filtres pour l'élimination Schwebstofffilter und Filtermedien zur Abscheidung

des particules dans l'air - Partie 2: Production von Partikeln aus der Luft - Teil 2: Aerosolerzeugung,

d'aérosol, équipement de mesure et statistique de Messgeräte und Partikelzählstatistik (ISO 29463-

comptage de particules (ISO 29463-2:2011) 2:2011)
This European Standard was approved by CEN on 6 May 2018.

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, 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

© 2018 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 29463-2:2018 E

worldwide for CEN national Members.
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SIST EN ISO 29463-2:2018
EN ISO 29463-2:2018 (E)
Contents Page

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

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SIST EN ISO 29463-2:2018
EN ISO 29463-2:2018 (E)
European foreword

The text of ISO 29463-2:2011 has been prepared by Technical Committee ISO/TC 142 "Cleaning

equipment for air and other gases” of the International Organization for Standardization (ISO) and has

been taken over as EN ISO 29463-2:2018 by 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 April 2019, and conflicting national standards shall be

withdrawn at the latest by April 2019.

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 1822-2:2009.

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, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,

Turkey and the United Kingdom.
Endorsement notice

The text of ISO 29463-2:2011 has been approved by CEN as EN ISO 29463-2:2018 without any

modification.
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SIST EN ISO 29463-2:2018
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SIST EN ISO 29463-2:2018
INTERNATIONAL ISO
STANDARD 29463-2
First edition
2011-10-15
High-efficiency filters and filter media for
removing particles in air —
Part 2:
Aerosol production, measuring
equipment and particle-counting
statistics
Filtres à haut rendement et filtres pour l'élimination des particules dans
l'air —
Partie 2: Production d'aérosol, équipement de mesure et statistique de
comptage de particules
Reference number
ISO 29463-2:2011(E)
ISO 2011
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SIST EN ISO 29463-2:2018
ISO 29463-2:2011(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2011

All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means,

electronic or mechanical, including photocopying and microfilm, without permission in writing 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 2011 – All rights reserved
---------------------- Page: 8 ----------------------
SIST EN ISO 29463-2:2018
ISO 29463-2:2011(E)
Contents Page

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

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

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

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

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

4  Aerosol production ............................................................................................................................... 2

4.1  Aerosol substances .............................................................................................................................. 2

4.2  Producing mono-disperse aerosols .................................................................................................... 3

4.3  Generating poly-disperse aerosols ..................................................................................................... 6

4.4  Neutralization of aerosols .................................................................................................................... 8

4.5  Minimum performance parameters for aerosol generators .............................................................. 8

4.6  Sources of error ..................................................................................................................................... 8

4.7  Maintenance and inspection ................................................................................................................ 8

5  Measuring devices ................................................................................................................................ 9

5.1  Optical particle counters ...................................................................................................................... 9

5.2  Condensation particle counter .......................................................................................................... 11

5.3  Differential mobility analyser ............................................................................................................. 14

5.4  Particle size analysis system on the basis of differential mobility analysis ................................. 16

5.5  Dilution systems .................................................................................................................................. 16

5.6  Aerosol photometer ............................................................................................................................ 17

5.7  Differential pressure measuring equipment ..................................................................................... 19

5.8  Absolute pressure measuring equipment ........................................................................................ 19

5.9  Thermometers ...................................................................................................................................... 19

5.10  Hygrometer .......................................................................................................................................... 20

6  Maintenance and inspection intervals .............................................................................................. 20

7  Particle counting statistics ................................................................................................................. 21

Annex A (informative) Mean size of particle size distributions .................................................................... 22

Bibliography ...................................................................................................................................................... 24

© ISO 2011 – All rights reserved iii
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SIST EN ISO 29463-2:2018
ISO 29463-2:2011(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 29463-2 was prepared by Technical Committee ISO/TC 142, Cleaning equipment for air and other gases.

ISO 29463 consists of the following parts, under the general title High-efficiency filters and filter media for

removing particles in air:
 Part 1: Classification, performance, testing and marking
 Part 2: Aerosol production, measuring equipment, particle-counting statistics
 Part 3: Testing flat sheet filter media
 Part 4: Test method for determining leakage of filter element — Scan method
 Part 5: Test method for filter elements
iv © ISO 2011 – All rights reserved
---------------------- Page: 10 ----------------------
SIST EN ISO 29463-2:2018
ISO 29463-2:2011(E)
Introduction

ISO 29463 (all parts) is derived from EN 1822 (all parts) with extensive changes to meet the requests from

non-EU p-members. It contains requirements, fundamental principles of testing and the marking for high-

efficiency particulate air filters with efficiencies from 95 % to 99,999 995 % that can be used for classifying

filters in general or for specific use by agreement between users and suppliers.

ISO 29463 (all parts) establishes a procedure for the determination of the efficiency of all filters on the basis of

a particle counting method using a liquid (or alternatively a solid) test aerosol, and allows a standardized

classification of these filters in terms of their efficiency, both local and overall efficiency, which actually covers

most requirements of different applications. The difference between ISO 29463 (all parts) and other national

standards lies in the technique used for the determination of the overall efficiency. Instead of mass

relationships or total concentrations, this technique is based on particle counting at the most penetrating

particle size (MPPS), which, for micro-glass filter mediums, is usually in the range of 0,12 µm to 0,25 µm. This

method also allows testing ultra-low penetration air filters, which was not possible with the previous test

methods because of their inadequate sensitivity. For membrane filter media, separate rules apply, and are

described in ISO 29463-5:2011, Annex B. Although no equivalent test procedures for testing filters with

charged media is prescribed, a method for dealing with these types of filters is described in ISO 29463-5:2011,

Annex C. Specific requirements for test method, frequency, and reporting requirements can be modified by

agreement between supplier and customer. For lower efficiency filters (group H, as described below),

alternate leak test methods noted in ISO 29463-4:2011, Annex A, can be used by specific agreement between

users and suppliers, but only if the use of these other methods is clearly designated in the filter markings as

described in ISO 29463-4:2011, Annex A.

There are differences between ISO 29463 (all parts) and other normative practices common in several

countries. For example, many of these rely on total aerosol concentrations rather than individual particles. For

information, a brief summary of these methods and their reference standards are provided in

ISO 29463-5:2011, Annex A.
© ISO 2011 – All rights reserved v
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SIST EN ISO 29463-2:2018
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SIST EN ISO 29463-2:2018
INTERNATIONAL STANDARD ISO 29463-2:2011(E)
High-efficiency filters and filter media for removing particles in
air —
Part 2:
Aerosol production, measuring equipment and particle-
counting statistics
1 Scope

This part of ISO 29463 specifies the aerosol production and measuring equipment used for testing high-

efficiency filters and filter media in accordance with ISO 29463-3, ISO 29463-4 and ISO 29463-5, as well as

the statistical basis for particle counting with a small number of counted events. It is intended to be used in

conjunction with ISO 29463-1, ISO 29463-3, ISO 29463-4 and ISO 29463-5.
2 Normative references

The following referenced documents are indispensable for the application 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 29463-1, High-efficiency filters and filter media for removing particles in air — Part 1: Classification,

performance, testing and marking

ISO 29463-3, High-efficiency filters and filter media for removing particles in air — Part 3: Testing flat sheet

filter media

ISO 29463-4:2011, High-efficiency filters and filter media for removing particles in air — Part 4: Test method

for determining the leakage of filter element — Scan method

ISO 29463-5:2011, High-efficiency filters and filter media for removing particles in air — Part 5: Test method

for filter elements
ISO 29464 , Cleaning equipment for air and other gases — Terminology
1) To be published.
© ISO 2011 – All rights reserved 1
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SIST EN ISO 29463-2:2018
ISO 29463-2:2011(E)
3 Terms and definitions

For the purposes of this document, the terms and definitions given in ISO 29463-1, ISO 29464, and the

following apply.
3.1
counting efficiency

expression of that proportion of the particles of detectable size suspended in the volume flow under analysis

that make their way through the measured volume and are counted by the particle counter

EXAMPLE The ratio of the concentration measured to actual aerosol concentration.

NOTE The counting efficiency depends on the particle size, and decreases progressively in the proximity of the lower

detection limit of the particle counter.
4 Aerosol production

When testing a filter, a test aerosol with liquid particles shall be used as reference test method in accordance

with ISO 29463-1. Alternatively, a solid PSL aerosol may be used for local efficiency (leak) testing (see

ISO 29463-4:2011, Annex E).

The testing of high-performance filters (ISO 65 U and higher) requires methods of aerosol production with high

10 1 11 1

production rates (10 s to 10 s ), in order to provide statistically significant measurements downstream

of the filter.

By adjusting the operating parameters of the aerosol generator, it shall be possible to adjust the mean particle

diameter of the aerosol so that it is equal to the MPPS. The concentration and the size distribution of the

aerosol produced shall remain constant throughout the test.
4.1 Aerosol substances

A suitable aerosol substance for the reference test method is a liquid with a vapour pressure that is so low at

the ambient temperature that the size of the droplets produced does not change significantly due to

evaporation over the time scale relevant for the test procedure (in the order of a few seconds).

4.1.1 Possible substances include, but are not limited to,
 DEHS,
 PAO,
 paraffin oil (low viscosity).

4.1.2 The most critical properties of a possible aerosol substance are the following, which should not differ

significantly from the values given for the three substances suggested in Table 1:

 index of refraction;
 vapour pressure;
 density.

Standard laboratory safety regulations shall be observed when handling these substances. It shall be ensured

by means of suitable exhaust systems and air-tight aerosol ducting systems that the test aerosols are not

inhaled. In case of doubt, the safety data sheets for the appropriate substances shall be consulted.

2 © ISO 2011 – All rights reserved
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SIST EN ISO 29463-2:2018
ISO 29463-2:2011(E)
Table 1 — Important data for aerosol substances at 20 °C
Trivial name DEHS PAO Paraffin oil (low visc.)
Chemical designation Sebacic Poly-alpha-olefin Mixture
acid-bis(2-ethylhexyl) ester (e.g. CAS No. 68649-12-7) (e.g. CAS # 64742-46-7)
(e.g. CAS No. 122-62-3)
Trivial name Diethylhexylsebacate Polyalphaolefin Paraffin oil
3 c
Density, kg/m 912 800 to 820 (820 )
843
Melting point, K 225 280
259
Boiling point, K 529 650 to 780 (674 )
526
Flash point, K 473 445 to 500
453
Vapour pressure at 293 K,
1,9  0,1 kPa at 423 K 0,1 to 0,13 0,1
kPa
0,003 1 to 0,003 4 at 373 K
0,026
Dynamic viscosity, kg/ms 0,022 to 0,024
0,014 at 313 K
0,002 5 to 0,003 8 at 313 K
Kinematic viscosity, mm /s — 3,8 to 4,2 at 373 K 3,0 to 4,5 at 313 K
1,450/650
1,452/600
1,4535/550
Index of
c c
(1,455 6) (1,466 )
refraction/wavelength, nm
1,4545/500
1,4585/450
1,475/400

US Patents 5,059,349, 5,059,352, and 5,076,965 describe and restrict the use of PAO for filter testing.

Material properties of PAO are as given in Japan JACA Standard No. 37-2001 and ISO 14644-3.

CAS #, Chemical Abstract Service Registry Number, substances have been registered in Chemical Abstract, issued by American

Chemical Society.
Data for “Emery 3004” as a specific example of a PAO.

Source: Crosby, David W., Concentration produced by a Laskin nozzle generator, a comparison of substitute materials and DOP,

21st DOE/NRC Nuclear Air Cleaning Conference.
4.2 Producing mono-disperse aerosols
4.2.1 Condensation methods

Condensation methods are preferred for the creation of mono-disperse aerosols, i.e. the particles are formed

by condensation from the vapour phase. It is necessary to distinguish between heterogeneous and

homogeneous condensation.
4.2.1.1 Heterogeneous condensation

In the case of heterogeneous condensation, the vapour condenses at a relatively low level of super-saturation

onto very small particles that are already present, the so-called condensation nuclei. The size distribution of

the resultant aerosol has a geometrical standard deviation between   1,05 and   1,15.

g g

One type of aerosol generator that operates using the principle of heterogeneous condensation and that is

suitable for testing filters in accordance with this part of ISO 29463 is the Rapaport-Weinstock generator (see

Figure 1).
© ISO 2011 – All rights reserved 3
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SIST EN ISO 29463-2:2018
ISO 29463-2:2011(E)
4.2.1.1.1 Rapaport-Weinstock generator
NOTE See Figure 1.

An aerosol substance is nebulized through a nozzle, either as a pure substance or in solution, and the

resultant poly-disperse aerosol is then vaporized along the heated section of a glass tube. Residual nuclei of

the impurities in the material remain.
Key
1 liquid reservoir
2 nebulizer
3 vaporization section
4 thermostat
5 condensation section
Compressed air.
Aerosol.
Figure 1 — Structure of the Rapaport and Weinstock aerosol generator

In the subsequent condensation section, the aerosol substance then condenses on these nuclei to form a

mono-disperse aerosol (see also Reference [1]).

The particle diameter of this aerosol is determined by the mixing ratio of aerosol substance and solvent. The

final aerosol contains the solvent used (e.g. propanol) as a vapour.
9 1

Generators of this type achieve particle production rates of 10 s ; the particle diameter can be adjusted

between approximately 0,1 µm and 1,5 µm.
4 © ISO 2011 – All rights reserved
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SIST EN ISO 29463-2:2018
ISO 29463-2:2011(E)
4.2.1.2 Homogeneous condensation

At higher levels of super-saturation, clusters of vapour molecules form spontaneously without the presence of

condensation nuclei, and these then grow to particles that are some nanometres in diameter (homogeneous

condensation). Larger particles then form as a result of coagulation of these particles with one another. The

resultant size distribution has a standard deviation of   1,5 independent of the median particle size, and

can thus only be referred to as quasi-mono-disperse. On the other hand, rates of production of particles

achieved can be as much as two orders of magnitude larger than those possible using heterogeneous

11 1
condensation (more than 10 s ).

Figure 2 shows the structure of a free-jet condensation aerosol generator that makes use of this principle.

2 1
Key
1 DEHS tank
2 pump
3 flow controller
4 ultra-sonic nebulizer
5 thermostat
6 vaporization pipe with heater and insulation
7 sheath air
8 nozzle
9 sintered metal plate
10 coagulation section
Nitrogen.
Aerosol.
Figure 2 — Set-up of a free-jet condensation aerosol generator
© ISO 2011 – All rights reserved 5
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SIST EN ISO 29463-2:2018
ISO 29463-2:2011(E)

A pump delivers aerosol substance to an ultrasonic nebulizer at a defined rate. The relatively large ( 20 µm)

droplets that are produced are then vaporized in a heated pipe. The concentration of residual nuclei is so low

that they do not influence the subsequent homogeneous condensation process. The hot stream of nitrogen

carrying the vapour then passes through a nozzle into a cold, laminar flow of sheath air. The turbulent mixing

of the free jet with the cold air produces the super-saturation necessary for the homogeneous condensation.

The particle size and particle concentration can be adjusted by varying the volume flow rates of the aerosol

substance (DEHS), nitrogen and envelope air.
4.2.2 Particle size classification

Using a differential mobility analyser as described in 5.3, it is possible to separate a fraction with almost the

same electrical mobility from a poly-disperse aerosol (see also Reference [2]). Provided all these particles

carry only a single electrical charge, then this mono-mobile fraction is also mono-disperse. If necessary, larger

particles that carry a multiple charge, and that thus have the same electrical mobility as the single-charged

particles, shall be removed from the poly-disperse input aerosol by suitable means.

Since the proportion of singly charged particles in the relevant size range is less than 10 %, from which only a

narrow size band is selected, then the number concentration of the mono-disperse output aerosol is lower

than the input concentration by a factor of at least 100. As a consequence, this method of producing mono-

disperse aerosols is suitable only for the measurement of the particle size efficiency of the filter medium (see

ISO 29463-3).

The degree of mono-dispersity achieved by this method can be described by a geometrical standard deviation

of   1,1. In practise, however, the operating parameters are often amended to increase the particle

concentration at the expense of a greater standard deviation.
4.3 Generating poly-disperse aerosols

Poly-disperse liquid aerosols are usually produced by nebulizing the aerosol substance through a binary

nozzle using compressed air.

A subsequent inertial separator, in the form of baffle plates or a cyclone separator, serves to precipitate larger

particles and to reduce the range of the size distribution. The geometrical standard deviation of the distribution

generated lies between 1,6 and 2,5. The particle diameter can be influenced to a small degree by changing

the operating pressure of the nozzle. Greater influence on the particle size is usually achieved by dissolving

the aerosol in a volatile solvent (e.g. propanol) before nebulization. When the solvent evaporates, it leaves

behind particles whose size is governed by the ratio of aerosol substance to solvent that was used.

It is comparatively simple to increase the particle production rate by using a number of jets in parallel.

10 1

The maximum rate of particle production that can be achieved using one nozzle is 5  10 s .

NOTE A typical jet nebulizer is described, for example, in Reference [3].

Where higher aerosol outputs are desired (ISO 29463-5), a Laskin Nozzle aerosol generator is recommended.

4.3.1 Laskin Nozzle poly-disperse aerosol generator

The Laskin Nozzle aerosol generator system uses a nozzle to generate a poly-disperse aerosol from a liquid,

such as DOP, DEHS or PAO and employs a source of compressed gas (see also Reference [4]). The

generator creates an aerosol having a mass mean diameter of approximately 0,45 µm, a light-scattering

geometric diameter of approximately 0,72 µm, and a light-scattering mean droplet-size distribution as shown

in Figure 3 (see also Reference [4]).
6 © ISO 2011 – All rights reserved
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SIST EN ISO 29463-2:2018
ISO 29463-2:2011(E)
Key
1 brass tubing, 9,5 mm (3/8 in) OD  1,7 mm (0,065 in) wall
2 brass collar, 15,9 mm (5/8 in ) OD, silver brazed to tubing 1

3 radial holes, 1 mm (0,04 in) diameter, 1,6 rad (90°) apart; top edge of holes just touching bottom of collar (4 required)

4 brass plug – Silver braze in place (full penetration)

5 2 mm (0,08 in) diameter longitudinal holes next to tube in line with radial holes (4 required)

Approximately 12,7 mm (1/2 in) above bottom of can.
Length variable to suit installation.
Tolerances are 0,05 mm for the dimensions on the holes.
Tolerances are 0,51 mm for all other dimensions.
[4]
Figure 3 — Details of a Laskin Nozzle
© ISO 2011 – All rights reserved 7
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SIST EN ISO 29463-2:2018
ISO 29463-2:2011(E)
4.3.2 Laskin Generator — Verification of pressure-flow characteristics
Detailed procedures are found in IEST RP CC013. An additional gravimetric s
...

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