kSIST FprEN ISO 16890-4:2022

Air filters for general ventilation - Part 4: Conditioning method to determine the minimum fractional test efficiency (ISO/FDIS 16890-4:2022)

This document establishes a conditioning method to determine the minimum fractional test efficiency.
It is intended to be used in conjunction with ISO 16890‑1, ISO 16890‑2 and ISO 16890‑3, and provides the related test requirements for the test device and conditioning cabinet as well as the conditioning procedure to follow.
The conditioning method described in this document is referring to a test device with a nominal face area of 610 mm × 610 mm (24 inches × 24 inches).
This document refers to particulate air filter elements for general ventilation having an ePM1 efficiency less than or equal to 99 % and an ePM10 efficiency greater than 20 % when tested according to the procedures defined within the ISO 16890 series.
NOTE      The lower limit for this test procedure is set at a minimum ePM10 efficiency of 20 % since it will be very difficult for a test filter element below this level to meet the statistical validity requirements of this procedure.
Filter elements used in portable room-air cleaners are excluded from the scope of this document.

Luftfilter für die allgemeine Raumlufttechnik - Teil 4: Konditionierungsverfahren für die Ermittlung des Fraktionsabscheidegradminimums (ISO/FDIS 16890-4:2022)

Filtres à air de ventilation générale -— Partie 4: Méthode de conditionnement afin de déterminer l'efficacité spectrale minimum d'essai (ISO/FDIS 16890-4:2022)

Le présent document établit une méthode de conditionnement pour déterminer l'efficacité spectrale minimum d'essai.
Il est destiné à être utilisé conjointement avec l'ISO 16890‑1, l'ISO 16890‑2 et l'ISO 16890‑3, et fournit les exigences d'essai associées pour le dispositif d'essai et l’enceinte de conditionnement ainsi que le mode opératoire de conditionnement à suivre.
La méthode de conditionnement décrite dans le présent document se réfère à un banc d’essai ayant une surface frontale nominale de 610 mm × 610 mm (24 inches × 24 inches).
Le présent document concerne les éléments filtrant de ventilation générale ayant une efficacité ePM1 inférieure ou égale à 99 % et une efficacité ePM10 supérieure à 20 %, lorsqu'ils sont soumis à essai selon les modes opératoires définis dans la série ISO 16890.
NOTE         La limite inférieure pour ce mode opératoire d’essai est fixée à une efficacité minimale ePM10 de 20 % étant donné qu’il est très difficile pour un élément filtrant d’essai en dessous de ce niveau de respecter les exigences de validité statistique de ce mode opératoire.
Les éléments filtrants utilisés dans les épurateurs d'air ambiant portatifs sont exclus du domaine d'application du présent document.

Zračni filtri pri splošnem prezračevanju - 4. del: Metoda kondicioniranja za ugotavljanje minimalne frakcijske učinkovitosti (ISO/FDIS 16890-4:2022)

General Information

• Status: Not Published
• Public Enquiry End Date: 30-Jun-2020
• ICS: 91.140.30 - Ventilation and air-conditioning systems
• Technical Committee: I13 - Imaginarni 13
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 07-Sep-2022
• Due Date: 12-Nov-2022
• Ref Project: EN ISO 16890-4:2022 - Air filters for general ventilation - Part 4: Conditioning method to determine the minimum fractional test efficiency (ISO 16890-4:2022)

RELATIONS

• Replaces: SIST EN ISO 16890-4:2017 - Air filters for general ventilation - Part 4: Conditioning method to determine the minimum fractional test efficiency (ISO 16890-4:2016)
• Effective Date: 07-Sep-2022

Standards Content (sample)

SLOVENSKI STANDARD
oSIST prEN ISO 16890-4:2020
01-junij-2020
Zračni filtri pri splošnem prezračevanju - 4. del: Metoda kondicioniranja za
ugotavljanje minimalne frakcijske učinkovitosti (ISO/DIS 16890-4:2020)

Air filters for general ventilation - Part 4: Conditioning method to determine the minimum

fractional test efficiency (ISO/DIS 16890-4:2020)

Luftfilter für die allgemeine Raumlufttechnik - Teil 4: Konditionierungsverfahren für die

Ermittlung des Fraktionsabscheidegradminimums (ISO/DIS 16890-4:2020)

Filtres à air de ventilation générale Partie 4: Méthode de conditionnement afin de

déterminer l'efficacité spectrale minimum d'essai (ISO/DIS 16890-4:2020)
Ta slovenski standard je istoveten z: prEN ISO 16890-4
ICS:
91.140.30 Prezračevalni in klimatski Ventilation and air-
sistemi conditioning systems
oSIST prEN ISO 16890-4:2020 en,fr,de

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

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oSIST prEN ISO 16890-4:2020
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oSIST prEN ISO 16890-4:2020
DRAFT INTERNATIONAL STANDARD
ISO/DIS 16890-4
ISO/TC 142 Secretariat: UNI
Voting begins on: Voting terminates on:
2020-04-14 2020-07-07
Air filters for general ventilation —
Part 4:
Conditioning method to determine the minimum fractional
test efficiency
Filtres à air de ventilation générale —

Partie 4: Méthode de conditionnement afin de déterminer l'efficacité spectrale minimum d'essai

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 16890-4:2020(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 2020
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oSIST prEN ISO 16890-4:2020
ISO/DIS 16890-4:2020(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2020

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

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

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

below or ISO’s member body in the country of the requester.
ISO copyright office
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Published in Switzerland
ii © ISO 2020 – All rights reserved
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oSIST prEN ISO 16890-4:2020
ISO/DIS 16890-4:2020(E)
Contents Page

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

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

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

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

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

4 Symbols and abbreviated terms ........................................................................................................................................................... 2

5 General conditioning test requirements ..................................................................................................................................... 2

5.1 General ........................................................................................................................................................................................................... 2

5.2 Test device requirements ............................................................................................................................................................... 2

5.3 Test device selection .......................................................................................................................................................................... 3

5.4 Conditioning cabinet requirements ...................................................................................................................................... 3

6 Conditioning materials .................................................................................................................................................................................. 3

7 Conditioning cabinet ........................................................................................................................................................................................ 4

7.1 General ........................................................................................................................................................................................................... 4

7.2 Conditioning cabinet dimensions and construction materials ..................................................................... 4

7.3 Environment, temperature and relative humidity ................................................................................................... 5

8 Safety issues .............................................................................................................................................................................................................. 6

9 Test method ............................................................................................................................................................................................................... 6

9.1 General ........................................................................................................................................................................................................... 6

9.2 Conditioning procedure .................................................................................................................................................................. 7

10 Qualification .............................................................................................................................................................................................................. 7

11 Reporting results ................................................................................................................................................................................................. 8

Annex A (informative) Hints for health and safety aspects for the use of IPA ...........................................................9

Bibliography .............................................................................................................................................................................................................................11

© ISO 2020 – All rights reserved iii
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oSIST prEN ISO 16890-4:2020
ISO/DIS 16890-4:2020(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 on 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 the following URL: www .iso .org/ iso/ foreword .html.

This document was prepared by Technical Committee ISO/TC 142, Cleaning equipment for air and

other gases.

This second edition cancels and replaces the first edition (ISO 16890-4:2016), which has been

technically revised.
The main changes compared to the previous edition are as follows:

— in 7.2 the dimensions of the conditioning cabinet are indicated in a more flexible way. This change

does not affect the test, however, it does make the procedure more reasonable for the users.

— in 9.2 a sentence has been added to make the proper procedure clear to the users.

A list of all parts in the ISO 16890 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 2020 – All rights reserved
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oSIST prEN ISO 16890-4:2020
ISO/DIS 16890-4:2020(E)
Introduction

The effects of particulate matter (PM) on human health have been extensively studied in the past

decades. The results are that fine dust can be a serious health hazard, contributing to or even causing

respiratory and cardiovascular diseases. Different classes of particulate matter can be defined according

to the particle size range. The most important ones are PM , PM and PM . The U.S. Environmental

10 2,5 1

Protection Agency (EPA), the World Health Organization (WHO) and the European Union define

PM as particulate matter which passes through a size-selective inlet with a 50 % efficiency cut-off

at 10 µm aerodynamic diameter. PM and PM are similarly defined. However, this definition is not

2,5 1

precise if there is no further characterization of the sampling method and the sampling inlet with a

clearly defined separation curve. In Europe, the reference method for the sampling and measurement

of PM is described in EN 12341. The measurement principle is based on the collection on a filter of the

PM fraction of ambient particulate matter and the gravimetric mass determination (see EU Council

Directive 1999/30/EC of 22 April 1999).

As the precise definition of PM , PM and PM is quite complex and not simple to measure, public

10 2,5 1

authorities, like the U.S. EPA or the German Federal Environmental Agency (Umweltbundesamt),

increasingly use in their publications the more simple denotation of PM as being the particle size

fraction less or equal to 10 µm. Since this deviation to the above mentioned complex “official” definition

does not have a significant impact on a filter element’s particle removal efficiency, the ISO 16890 series

refers to this simplified definition of PM , PM and PM .
10 2,5 1

Particulate matter in the context of the ISO 16890 series describes a size fraction of the natural aerosol

(liquid and solid particles) suspended in ambient air. The symbol ePM describes the efficiency of an air

cleaning device to particles with an optical diameter between 0,3 µm and x µm. The following particle

size ranges are used in the ISO 16890 series for the listed efficiency values.

Table 1 — Optical particle diameter size ranges for the definition of the efficiencies, ePM

Efficiency Size range, µm
ePM 0,3 ≤ × ≤10
ePM 0,3 ≤ × ≤2,5
2,5
ePM 0,3 ≤ × ≤1

Air filters for general ventilation are widely used in heating, ventilation and air-conditioning applications

of buildings. In this application, air filters significantly influence the indoor air quality and, hence, the

health of people, by reducing the concentration of particulate matter. To enable design engineers and

maintenance personnel to choose the correct filter types, there is an interest from international trade

and manufacturing for a well-defined, common method of testing and classifying air filters according

to their particle efficiencies, especially with respect to the removal of particulate matter. Current

regional standards are applying totally different testing and classification methods, which do not allow

any comparison with each other, and thus hinder global trade with common products. Additionally,

the current industry standards have known limitations by generating results which often are far away

from filter performance in service, i.e. overstating the particle removal efficiency of many products.

With this new ISO 16890 series, a completely new approach for a classification system is adopted, which

gives better and more meaningful results compared to the existing standards.

The ISO 16890 series describes the equipment, materials, technical specifications, requirements,

qualifications and procedures to produce the laboratory performance data and efficiency classification

based upon the measured fractional efficiency converted into a particulate matter efficiency (ePM)

reporting system.

Air filter elements according to the ISO 16890 series are evaluated in the laboratory by their ability

to remove aerosol particulate expressed as the efficiency values ePM , ePM and ePM The air filter

1 2,5 10.

elements can then be classified according to the procedures defined in ISO 16890-1. The particulate

removal efficiency of the filter element is measured as a function of the particle size in the range of

0,3 μm to 10 µm of the unloaded and unconditioned filter element as per the procedures defined in

ISO 16890-2. After the initial particulate removal efficiency testing, the air filter element is conditioned

© ISO 2020 – All rights reserved v
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oSIST prEN ISO 16890-4:2020
ISO/DIS 16890-4:2020(E)

according to the procedures defined in this part of ISO 16890 and the particulate removal efficiency is

repeated on the conditioned filter element. This is done to provide information about the intensity of

any electrostatic removal mechanism which may or may not be present with the filter element for test.

The average efficiency of the filter is determined by calculating the mean between the initial efficiency

and the conditioned efficiency for each size range. The average efficiency is used to calculate the ePM

efficiencies by weighting these values to the standardized and normalized particle size distribution of

the related ambient aerosol fraction. When comparing filters tested in accordance with the ISO 16890

series, the fractional efficiency values shall always be compared among the same ePM class (ex. ePM

x 1

of filter A with ePM of filter B). The test dust capacity and the initial arrestance of a filter element are

determined as per the test procedures defined in ISO 16890-3.
vi © ISO 2020 – All rights reserved
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oSIST prEN ISO 16890-4:2020
DRAFT INTERNATIONAL STANDARD ISO/DIS 16890-4:2020(E)
Air filters for general ventilation —
Part 4:
Conditioning method to determine the minimum fractional
test efficiency
1 Scope

This part of ISO 16890 establishes a conditioning method to determine the minimum fractional test

efficiency.

It is intended for use in conjunction with ISO 16890-1, ISO 16890-2 and ISO 16890-3, and provides

the related test requirements for the test device and conditioning cabinet as well as the conditioning

procedure to follow.

The conditioning method described in this part of ISO 16890 is referring to a test device with a nominal

face area of 610 mm × 610 mm (24 inch × 24 inch).

ISO 16890 (all parts) refers to particulate air filter elements for general ventilation having an ePM

efficiency less than or equal to 99 % and an ePM efficiency greater than 20 % when tested according

to the procedures defined within ISO 16890 (all parts).

NOTE The lower limit for this test procedure is set at a minimum ePM efficiency of 20 % since it will be very

difficult for a test filter element below this level to meet the statistical validity requirements of this procedure.

Air filter elements outside of this aerosol fraction are evaluated by other applicable test methods. See

ISO 29463 (all parts).

Filter elements used in portable room-air cleaners are excluded from the scope of this part of ISO 16890.

The performance results obtained in accordance with ISO 16890 (all parts) cannot by themselves be

quantitatively applied to predict performance in service with regard to efficiency and lifetime.

The results from this part of ISO 16890 may also be used by other standards that define or classify the

fractional efficiency in the size range of 0,3 μm to 10 μm when electrostatic removal mechanism is an

important factor to consider, for example ISO 29461.
2 Normative references

The following documents, in whole or in part, are normatively referenced in this document and are

indispensable for its application. For dated references, only the edition cited applies. For undated

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

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

classification system based upon particulate matter efficiency (ePM)

ISO 16890-2, Air filters for general ventilation — Part 2: Measurement of fractional efficiency and air flow

resistance

ISO 16890-3, Air filters for general ventilation — Part 3: Determination of the gravimetric efficiency and

the air flow resistance versus the mass of test dust captured
ISO 29464, Cleaning of air and other gases — Terminology
© ISO 2020 – All rights reserved 1
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oSIST prEN ISO 16890-4:2020
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3 Terms and definitions

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

3.1
minimum fractional test efficiency

fractional efficiency after applying the conditioning method defined in this part of ISO 16890

Note 1 to entry: Also named as “minimum filter efficiency” or “minimum test efficiency”.

Note 2 to entry: Minimum fractional test efficiency shall be measured according to ISO 16890-2.

[SOURCE: ISO 29464:2017, 3.2.108, modified]
4 Symbols and abbreviated terms
IPA isopropyl alcohol (isopropanol)
MSDS material safety data sheet
5 General conditioning test requirements
5.1 General

This procedure is used to determine the minimum test efficiency and to test whether the filter fractional

efficiency is dependent on the electrostatic removal mechanism. This is accomplished by measuring the

removal efficiency of an untreated filter and the corresponding efficiency after conditioning.

Many types of air filters rely to different extents on the effects of passive electrostatic charges on the

fibres to achieve higher particle removal efficiencies, particularly in the initial stages of their working

life, at low resistance to airflow.

Exposure to some types of challenge, such as combustion particles, fine particles or oil mist in service

may affect the action of these electric charges so that the initial efficiency may drop substantially after

an initial period of service. This drop in the fractional efficiency can be reduced by a slight increase in

mechanical efficiency from the collection of particles in the filtration media. The amount of the drop

and the amount of the increase can vary by filter type, service location and atmospheric air conditions.

The procedure described here indirectly but quantitatively shows the extent of the electrostatic charge

effect on the initial performance on a full size filter (measured according to ISO 16890-2). It indicates the

level of efficiency obtainable with the charge effect removed (or minimized by IPA vapour conditioning)

and with no increase in mechanical efficiency. It should not be assumed that the measured conditioned

(“discharged”) efficiency always represents real life behaviour. The treatment of a filter as described

in this part of ISO 16890 may affect the structure of the fibre matrix or chemically affect the fibres or

even fully destroy the filter medium. Hence, this procedure may not be applicable to all types of filters.

If degradation shows a visual, physical change or a resistance to airflow change of more than 10 % but

minimum 10 Pa, this part of ISO 16890 is not applicable and the filter cannot be classified according to

ISO 16890-1.
5.2 Test device requirements

The test device shall be designed or marked so as to prevent incorrect mounting. The complete test

device (filter and frame) shall be made of material suitable to withstand normal usage and exposure

to the range of temperature, humidity and corrosive environments likely to be encountered in service.

2 © ISO 2020 – All rights reserved
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oSIST prEN ISO 16890-4:2020
ISO/DIS 16890-4:2020(E)
5.3 Test device selection

The test device shall be mounted in accordance with the manufacturer’s recommendations and,

after equilibration to standard climatic conditions, weighed to the nearest gram. Before starting the

conditioning, the initial resistance to airflow and initial fractional efficiency shall be determined

according to the measurement procedure described in ISO 16890-2.

The test device shall be a full size filter element with a nominal face dimension of 610 mm × 610 mm

(24 inch × 24 inch) with a maximum length (depth) of 760 mm (30 inch). If for any reason dimensions do

not allow conditioning of a test device under standard test conditions, assembly of two or more smaller

devices of the same type or model is permitted, provided no leaks occur in the resulting assembly. For

filters with a higher length or depth, the conditioning cabinet described in 7.1 can be scaled accordingly.

The operating conditions of such accessory equipment shall be recorded.
5.4 Conditioning cabinet requirements

Critical dimensions and arrangements of the conditioning cabinet are shown in the figures of this

part of ISO 16890 and are intended as guides to help construct a conditioning cabinet to meet the

performance requirements of this part of ISO 16890. All dimensions shown are mandatory unless

otherwise indicated. Units shown are in mm (inch) unless otherwise indicated.

The design of equipment not specified (including but not limited to the holding frame, IPA trays,

conditioning cabinet surroundings and auxiliaries) is discretionary, but the equipment shall have

adequate capacity to meet the performance and health and safety requirements described in Clause 8.

6 Conditioning materials

The liquid for the conditioning step to discharge filter media and equalize electrostatic surface charges

on the filter fibres is isopropyl alcohol (IPA, commonly known as isopropanol or 2-propanol). IPA is

placed inside the conditioning cabinet to evaporate until the equilibrium of IPA vapour in ambient air is

reached. So liquid IPA will not be in contact with the filter media.

This part of ISO 16890 does not claim to treat all possible related health and safety issues. It is the

responsibility of the user of this part of ISO 16890 to take suitable measures for the health and safety

protection of the staff before applying this method. Additionally, the responsible user shall take care

that official and legal regulations are fully respected.
Isopropanol (IPA) – formula: C H O
3 8
HCCH CH
Isopropanol properties:
Density 0,785 5 kg/m
Molecular weight 60,09 g/mol
Melting point 185 K
Boiling point 355 K
Flash point 285 K
Ignition temperature 698 K

Vapour pressure 0,059 7 bar (at 298 K)/0,043 2 bar (at 293 K)/0,081 4 bar (at 303 K)

To be calculated as follows:
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oSIST prEN ISO 16890-4:2020
ISO/DIS 16890-4:2020(E)
log PA=−
TC+
where
P = pressure (bar) T = temperature (K)
A = 4,577 95 B = 1 221,423
C = −87,474
NOTE 1 bar = 100 kPa.

Explosion limits (in air) Lower concentration limit 2 % (vol.), Upper concentration limit 12 % (vol.)

both at 293 K
CAS-number 67-63-0
For the conditioning test, IPA shall have a purity of minimum 99,5 %.
7 Conditioning cabinet
7.1 General

The conditioning cabinet shall consist of a filter holding chamber and one or two IPA tray holding

chambers. Each chamber may have separate doors for service. The filter holding chamber shall allow

the installation of a full size filter (the test device) in a way that the filter does not touch the conditioning

cabinet walls and allows air/vapour to pass around freely by diffusion. There shall be an open air

passage between the IPA tray holding chamber and the filter holding chamber to guarantee that the

mixture of air and IPA vapour can equilibrate in the whole conditioning cabinet volume as easily as

possible. To make sure that test devices with non-rigid, self-supporting structures, like bag filters, are

installed in the proper way and offer the full media surface to the air/vapour mixture, the filter holding

frame is in a horizontal position and the test device is hanging vertically (dust air side of the filter to the

top, clean air side to the bottom of the chamber).
7.2 Conditioning cabinet dimensions and construction materials

The conditioning cabinet shall be made of stainless or galvanized steel. IPA vapour is denser than

air and can stratify within the chamber, possibly causing all areas of the filter not to be subjected to

the concentration of IPA vapour. Therefore, the positioning of several IPA trays inside the IPA holding

chamber of the cabinet is adjacent to the filter holding chamber, so that an equal distribution of IPA

vapour within the cabinet is achieved quickly.

The conditioning cabinet shall be capable of containing a full size filter with face dimensions of

610 mm × 610 mm (24 inch × 24 inch). The maximum length/depth of the test device shall be 760 mm

(30 inch). To allow the air to pass freely around the test device by diffusion, the outer filter holding

3 3 3 3

chamber volume shall be between 0,45 m (15,9 ft ) and 0,65 m (23,0 ft ). The filter holding chamber

recommended dimensions are 750 mm × 750 mm × 850 mm (29,5 inch × 29,5 inch × 33,5 inch). Figure 1

shows the recommended size and dimensions of the conditioning cabinet.
4 © ISO 2020 – All rights reserved
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oSIST prEN ISO 16890-4:2020
ISO/DIS 16890-4:2020(E)
Dimensions in mm
Figure 1 — Conditioning cabinet schematic drawing

To make sure that the air inside the conditioning cabinet will be saturated with IPA very quickly, a total

of at least 1 dm (= 786 g, 34 fl oz or 0,028 oz) liquid IPA shall be filled into the trays before starting the

2 2

conditioning. The trays shall offer at least 1,0 m (10,8 ft ) free surface area for IPA evaporation. Each

tray shall be filled with liquid IPA and covered before starting the conditioning procedure. The mixture

of ambient air and IPA in the conditioning cabinet shall not interact with the ambient air (proper seal).

The container with IPA shall not come into direct contact with sunlight or any other heat radiation

that may alter the vapour characteristics significantly. Through respecting this and controlling the

temperature and humidity within the specified ranges, there is no need for instrumentation to verify

the IPA vapour concentration surrounding the test device as the air in the chamber is almost saturated

with IPA vapour.

The trays with liquid IPA shall be uncovered and placed inside the filter housing. After closing the

cabinet door, wait for 30 min. Then open the filter door and place the test device inside (upstream side

towards IPA – vertical/horizontal).

Close the door tightly. Once the conditioning time is reached, open the door and immediately remove

the test device. Finally, pull
...