SIST EN ISO 12569:2013
(Main)Thermal performance of buildings and materials - Determination of specific airflow rate in buildings - Tracer gas dilution method (ISO 12569:2012)
Thermal performance of buildings and materials - Determination of specific airflow rate in buildings - Tracer gas dilution method (ISO 12569:2012)
This International Standard establishes an engineering standard by which to obtain the ventilation rate/specific airflow rate, using a tracer gas in a building space, which is considered to be of a single zone. The measurement method is valid in spaces where the combined conditions concerning the uniformity of tracer gas concentration, measurement of the exhaust gas concentration, effective mixed zone and/or fluctuation of ventilation are satisfied. This International Standard provides three measurement methods using a tracer gas: (1) concentration decay method, (2) continuous dose method, and (3) constant concentration method.
Wärmetechnisches Verhalten von Gebäuden und Werkstoffen - Bestimmung des spezifischen Luftvolumenstroms in Gebäuden - Indikatorgasverfahren (ISO 12569:2012)
Diese Europäische Norm beschreibt die Anwendung des Indikatiorverfahrens zur Bestimmung der Luftwechselrate/des spezifischen Luftvolumenstroms in einem Raum eines Gebäudes, der als aus einer einzelnen Zone bestehend angesehen wird.
1) Das Prüfverfahren gilt für Räume, in denen die Luft gut durchmischt ist. Insbesondere sollten keine starken Luftströme wie z. B. Querlüftung vorliegen.
2) Diese Europäische Norm umfasst drei Prüfverfahren, bei denen Indikatorgas zum Einsatz kommt: (1) Prüfverfahren mit abfallender Konzentration, (2) Prüfverfahren mit konstanter Injektion und (3) Prüfverfahren mit konstanter Konzentration.
ANMERKUNG 1 In Räumen, in denen eine intensive Lüftung auftritt, beispielsweise Querlüftung, ist die Konzentration nicht gleichmäßig verteilt, und es besteht die Tendenz zum Auftreten großer Konzentrationsänderungen über die Zeit; daher werden sie hier nicht behandelt. Ist jedoch die Strömungsrichtung ersichtlich, wie dies beispielsweise bei der Strömung in einer Luftleitung der Fall ist, kann der spezifische Luftvolumenstrom unter Anwendung des Verfahrens mit konstanter Injektion beurteilt werden.
ANMERKUNG 2 Die Messgenauigkeit des sogenannten Verfahrens mit ansteigender Konzentration ist relativ schlecht, daher wird dieses Verfahren selten angewendet und wird auch hier nicht aufgeführt.
Performance thermique des bâtiments et des matériaux - Détermination du débit volumique d'air dans les bâtiments - Méthode de dilution de gaz traceurs (ISO 12569:2012)
L'ISO 12569:2012 établit un référentiel technique permettant d'obtenir le taux de ventilation/débit d'air spécifique à l'aide d'un gaz traceur, dans un espace intérieur d'un bâtiment, considéré comme ne comprenant qu'une seule zone.
La méthode de mesurage est valide dans les espaces où les conditions combinées relatives à l'uniformité de la concentration du gaz traceur, la mesure de la concentration du gaz, la zone de mélange réelle et/ou la fluctuation de la ventilation sont satisfaites.
L'ISO 12569:2012 propose trois méthodes de mesurage faisant appel à un gaz traceur: (1) la méthode par décroissance de la concentration, (2) la méthode par dose continue et (3) la méthode par concentration constante.
Toplotna izolacija v stavbah - Ugotavljanje števila izmenjav zraka v stavbah - Metoda redčenja indikatorskega plina (ISO 12569:2012)
Ta mednarodni standard določa inženirski standard, s katerim se določi stopnja ventilacije/število izmenjav zraka z indikatorskim plinom v prostoru stavb, ki se šteje za posamezno cono. Merilna metoda je veljavna v prostorih, v katerih so izpolnjeni kombinirani pogoji v zvezi z enotnostjo koncentracije indikatorskega plina, merjenjem koncentracije izpušnega plina, učinkovito mešano cono in/ali pretokom ventilacije. Ta mednarodni standard določa tri merilne metode z indikatorskim plinom: (1) metoda razgradnje koncentracije, (2) metoda nepretrganega odmerka in (3) metoda stalne koncentracije.
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN ISO 12569:2013
01-marec-2013
1DGRPHãþD
SIST EN ISO 12569:2001
7RSORWQDL]RODFLMDYVWDYEDK8JRWDYOMDQMHãWHYLODL]PHQMDY]UDNDYVWDYEDK
0HWRGDUHGþHQMDLQGLNDWRUVNHJDSOLQD ,62
Thermal performance of buildings and materials - Determination of specific airflow rate in
buildings - Tracer gas dilution method (ISO 12569:2012)
Wärmetechnisches Verhalten von Gebäuden und Werkstoffen - Bestimmung des
spezifischen Luftvolumenstroms in Gebäuden - Indikatorgasverfahren (ISO 12569:2012)
Performance thermique des bâtiments et des matériaux - Détermination du débit
volumique d'air dans les bâtiments - Méthode de dilution de gaz traceurs (ISO
12569:2012)
Ta slovenski standard je istoveten z: EN ISO 12569:2012
ICS:
91.120.10 Toplotna izolacija stavb Thermal insulation
SIST EN ISO 12569:2013 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN ISO 12569:2013
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SIST EN ISO 12569:2013
EUROPEAN STANDARD
EN ISO 12569
NORME EUROPÉENNE
EUROPÄISCHE NORM
December 2012
ICS 91.120.10 Supersedes EN ISO 12569:2000
English Version
Thermal performance of buildings and materials - Determination
of specific airflow rate in buildings - Tracer gas dilution method
(ISO 12569:2012)
Performance thermique des bâtiments et des matériaux - Wärmetechnisches Verhalten von Gebäuden und
Détermination du débit d'air spécifique dans les bâtiments - Werkstoffen - Bestimmung des spezifischen
Méthode de dilution de gaz traceurs (ISO 12569:2012) Luftvolumenstroms in Gebäuden - Indikatorgasverfahren
(ISO 12569:2012)
This European Standard was approved by CEN on 17 November 2012.
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
© 2012 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 12569:2012: E
worldwide for CEN national Members.
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SIST EN ISO 12569:2013
EN ISO 12569:2012 (E)
Contents Page
Foreword .3
2
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SIST EN ISO 12569:2013
EN ISO 12569:2012 (E)
Foreword
This document (EN ISO 12569:2012) has been prepared by Technical Committee ISO/TC 163 "Thermal
performance and energy use in the built environment" in collaboration with Technical Committee CEN/TC 89
“Thermal performance of buildings and building components” the secretariat of which is held by SIS.
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 June 2013, and conflicting national standards shall be withdrawn at
the latest by June 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.
This document supersedes EN ISO 12569:2000.
According to the CEN/CENELEC Internal Regulations, the national standards organisations 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 12569:2012 has been approved by CEN as a EN ISO 12569:2012 without any modification.
3
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SIST EN ISO 12569:2013
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SIST EN ISO 12569:2013
INTERNATIONAL ISO
STANDARD 12569
Second edition
2012-12-01
Thermal performance of buildings and
materials — Determination of specific
airflow rate in buildings — Tracer gas
dilution method
Performance thermique des bâtiments et des matériaux —
Détermination du débit d’air spécifique dans les bâtiments —
Méthode de dilution de gaz traceurs
Reference number
ISO 12569:2012(E)
©
ISO 2012
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SIST EN ISO 12569:2013
ISO 12569:2012(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2012
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
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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 2012 – All rights reserved
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SIST EN ISO 12569:2013
ISO 12569:2012(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Terms and definitions . 1
3 Measurement method and its selection . 2
3.1 General . 2
3.2 Concentration decay method . 4
3.3 Continuous dose method . 7
3.4 Constant concentration method . 9
3.5 Type of tracer gas.10
3.6 Measurement apparatus .11
4 Procedure.13
4.1 Building preparations .13
4.2 Ancillary measurements .13
4.3 Concentration decay method .13
4.4 Continuous dose methods .20
4.5 Constant concentration method .25
5 Accuracy .27
5.1 Tracer gas dose procedure and room concentration distribution .28
5.2 Tracer gas sampling and storage method .28
5.3 Tracer gas concentration measuring instruments .28
5.4 Changes in outside wind and outside air temperature and schedule of air
conditioning system .29
6 Test report .29
6.1 General .29
6.2 All details necessary to identify the simulation tested.29
6.3 Details of heating and ventilation systems .29
6.4 Test conditions and apparatus .30
6.5 Collected data and results .30
6.6 Date of the test .30
Annex A (normative) Confidence intervals .31
Annex B (normative) Method to estimate ventilation rate Q and effective mixed zone volume V
V emz
[3,4]
simultaneously .34
Annex C (informative) Considerations when measuring the ventilation rate of large spaces .39
Annex D (informative) Effects of internal and external temperature difference, temperature
change, and outside air concentration change during the measurement period .40
Annex E (informative) Estimation error minimizing method in 2-point and multi-point
decay method .44
Annex F (informative) Propagation of error analysis .49
Bibliography .51
© ISO 2012 – All rights reserved iii
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SIST EN ISO 12569:2013
ISO 12569:2012(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 12569 was prepared by Technical Committee ISO/TC 163, Thermal performance and energy use in the
built environment, Subcommittee SC 1, Test and measurement methods.
This second edition cancels and replaces the first edition (ISO 12569:2000), which has been
technically revised.
iv © ISO 2012 – All rights reserved
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SIST EN ISO 12569:2013
ISO 12569:2012(E)
Introduction
The aim of ventilation is to maintain a proper hygienic status of the room by introducing outdoor air into
a room, diluting contaminants, heat, moisture or odour generated in the room, and evacuating them.
In terms of energy savings, it is also important to keep the ventilation at the required rate, in order to
reduce heat loss and heat gain under air conditioning as much as possible. Measurement of airflow rates
is often necessary, for example to check if the performance of a ventilation system is as intended, to
assess the source strength of contaminants, to ensure that contaminants are properly eliminated, etc.
The methods described here can be used to measure the ventilation rate or the specific airflow rate.
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SIST EN ISO 12569:2013
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SIST EN ISO 12569:2013
INTERNATIONAL STANDARD ISO 12569:2012(E)
Thermal performance of buildings and materials —
Determination of specific airflow rate in buildings —
Tracer gas dilution method
1 Scope
This International Standard establishes an engineering standard by which to obtain the ventilation
rate/specific airflow rate, using a tracer gas in a building space, which is considered to be of a single zone.
The measurement method is valid in spaces where the combined conditions concerning the uniformity
of tracer gas concentration, measurement of the exhaust gas concentration, effective mixed zone and/or
fluctuation of ventilation are satisfied.
This International Standard provides three measurement methods using a tracer gas: (1) concentration
decay method, (2) continuous dose method, and (3) constant concentration method.
NOTE Specific measurement conditions are given in Table 1.
2 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
2.1
single zone
V
space where the ventilation rate/specific airflow rate is measured and which only exchanges air
with the outside
NOTE 1 Measured in cubic metres.
NOTE 2 Conditions needed for measurement are different for each measurement method, and details are
given in Clause 4.
2.2
effective mixed zone
V
emz
space within a single zone, excluding sealed furniture or storage space, in which tracer gas supplied to
the zone is regarded as uniformly distributed
NOTE 1 Measured in cubic metres.
NOTE 2 Forced mixing of air in the zone is often needed to keep uniform tracer gas concentration.
2.3
ventilation rate
Q
v
total volume of air passing through the zone to the outdoor air per unit of time
3 3
NOTE Measured in m /s or m /h.
2.4
specific airflow rate
N
ratio of the Qv to the volume of the effective mixed zone, per second or per hour
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SIST EN ISO 12569:2013
ISO 12569:2012(E)
2.5
building envelope
boundary or barrier separating the interior volume of a building from the outside environment
2.6
tracer gas
gas that can be mixed with air and measured in very small concentration in order to study airflow rate
NOTE The tracer gas volume is defined as the value of exhaust temperature converted into density. When the
room air is mixed well, the room temperature approximately matches the exhaust temperature.
2.7
concentration decay method
method by which the specific airflow rate is obtained from the decaying curve of concentration observed
after the end of the injection of tracer gas.
2.8
continuous dose method
method by which the ventilation rate is obtained from the concentration resulting from continuous
generation or injection of the tracer gas
2.9
constant concentration method
method by which the ventilation rate is obtained from the injection rate of tracer gas dosed for constant
concentration in the space
3 Measurement method and its selection
3.1 General
One of the three measurement methods concentration decay method, continuous dose method and
constant concentration method, is used to measure the ventilation rate/specific airflow rate. Selection
of a measurement method and data processing depends on a building structure, ventilation system and
measurement instrument employed. The concentration decay method has a limited measurement time
of up to several hours while the continuous dose and constant concentration methods can provide a
longer measurement time up to several weeks. The guideline of selection of the method and what is
measured by the method is listed in Table 1.
In order to improve the accuracy of measuring the ventilation rate/specific airflow rate, it is sometimes
necessary to devise measures that approximate prerequisite conditions demanded of measurement
methods. In particular, if a measurement method were used that requires uniformity of concentration
in the effective mixed zone, it would be preferable to forcibly mix the internal air. In general, forced
mixing of internal air has little effect on ventilation rate/specific airflow rate, but there is a risk that
forced mixing affects the measured ventilation rate if natural ventilation due to temperature differences
predominates and the temperature within the room is distributed significantly, or if airflow emitted
from a fan for the purpose of mixing air directly impinges on the leakage areas in buildings. In such
instances, a mixing system needs to be improved or it would be recommended to select a measurement
method that could ensure uniformity of concentration without mixing.
In Table 1, specifications for the various applications are described as follows:
— “Room concentration can be maintained uniform at initial stage only” means making the
concentration in the effective mixed zone uniform by a method such as forced mixing when
supplying a tracer gas into the zone, but allowing the concentration to be distributed in principle
with the measurement.
— If it is specified that “room concentration can be maintained uniform at all times”, continuous forced
mixing of air in the effective mixed zone is preferable. However, if the constant concentration method
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SIST EN ISO 12569:2013
ISO 12569:2012(E)
is used, and if concentration is controlled by injecting the tracer gas at several places and air is
sampled at several locations, it is possible to assume that concentration is uniform without mixing.
— “Average exhaust concentration can be measured” may either mean instances in which concentration in
an effective mixed zone is made uniform using mixing, or instances whereby the pressure inside a zone is
kept lower than the outside when using the exhaust ventilation system, or the leakage area is extremely
low so the exfiltration rate may be ignored, and exhaust pathways may be specified beforehand.
— When using measurement methods that require the “known volume of an effective mixed zone”,
the volume of the effective mixed zone can be estimated using room dimensions. However, when
using the corresponding average inverse concentration method and average concentration method,
if a sufficiently long time is taken to evaluate the ventilation rate, high accuracy for estimating the
volume of an effective mixed zone is not needed.
— Measurement methods that can be applied in instances where “fluctuation in ventilation rate can
be ignored”, are designed on the assumption that the ventilation rate/specific airflow rate over time
does not change.
Table 1 — Method, application and measured quantities
Application and measured quantities
Application What is measured
Room Room Average Known Fluctuation Ventilation Flexibility
concentra- concen-tra- exhaust volume of in ventila- rate or spe- to transient
Method
tion can be tion can be concen-tra- effective tion rate can cific airflow ventilation
maintained maintained tion can be mixed zone be ignored rate rate
uniform at uniform at measured
initial stage all times
only
Concentra- 2-point
Specific air-
tion decay decay ○ Δ
flow rate
method method
Multi-
point Specific air-
○ ○
decay flow rate
method
Step-
down
exhaust Specific air-
○ ○ ○
concen- flow rate
tration
method
Pulse Ventilation
○ ○
method rate
NOTE In addition to the measurement methods above, there is an intermittent dose method that allows the measurement
the volume of an effective mixed zone and ventilation rate at the same time. For measurement of ventilation rate among the
other measurements, if volume of an effective mixed zone is known, the ventilation rate can be obtained by multiplying the
volume of the effective mixed zone by the specific airflow rate, and then converting to ventilation rate. The measurement
methods marked with “Δ” in the “flexibility to transient ventilation rate” column can apply, in principle, to the case where
changes in ventilation rate/specific airflow rate cannot be ignored, however, because the measurement is based on time-
mean ventilation rate/specific airflow rate, it indicates that it does not meet the measurement of transient ventilation
rate/specific airflow rate. The constant concentration methods marked with “○” indicate it meets measurement of transient
ventilation rate if the dose of the tracer gas responds accurately to the transient ventilation rate with internal concentration
maintained at a constant level.
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SIST EN ISO 12569:2013
ISO 12569:2012(E)
Table 1 (continued)
Application and measured quantities
Application What is measured
Room Room Average Known Fluctuation Ventilation Flexibility
concentra- concen-tra- exhaust volume of in ventila- rate or spe- to transient
Method
tion can be tion can be concen-tra- effective tion rate can cific airflow ventilation
maintained maintained tion can be mixed zone be ignored rate rate
uniform at uniform at measured
initial stage all times
only
Continu- Aver-
ous dose age of
method inverse Ventilation
○ ○ Δ
concen- rate
tration
method
Average
concen- Ventilation
○ ○ ○
tration rate
method
Station-
ary
Ventilation
concen- ○ ○
rate
tration
method
Constant concentra- Ventilation
○ ○
tion method rate
NOTE In addition to the measurement methods above, there is an intermittent dose method that allows the measurement
the volume of an effective mixed zone and ventilation rate at the same time. For measurement of ventilation rate among the
other measurements, if volume of an effective mixed zone is known, the ventilation rate can be obtained by multiplying the
volume of the effective mixed zone by the specific airflow rate, and then converting to ventilation rate. The measurement
methods marked with “Δ” in the “flexibility to transient ventilation rate” column can apply, in principle, to the case where
changes in ventilation rate/specific airflow rate cannot be ignored, however, because the measurement is based on time-
mean ventilation rate/specific airflow rate, it indicates that it does not meet the measurement of transient ventilation
rate/specific airflow rate. The constant concentration methods marked with “○” indicate it meets measurement of transient
ventilation rate if the dose of the tracer gas responds accurately to the transient ventilation rate with internal concentration
maintained at a constant level.
3.2 Concentration decay method
3.2.1 General
At the start of measurement, the tracer gas is supplied in the zone to be measured, and ventilation
rate/specific airflow rate is evaluated based on the concentration decay data obtained. In case of
the forced mixing for uniform distribution or if the average exhaust concentration can be measured,
the measurement point can be limited to one. The amount of tracer gas needed is very small for one
measurement, and it is not required to accurately measure the amount of injected gas except for the
pulse method.
The basic equation that can be commonly applied to the methods is as follows:
dV ()t
gas
3 3
=−Ct()Qv()t (m /h or m /s)
E
dt
(1)
where
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SIST EN ISO 12569:2013
ISO 12569:2012(E)
t is time, hours or seconds;
V (t)
gas
is total volume of tracer gas in a zone at time “t” ( = Cx,tdV ) (m³);
∫∫∫ ()
V
x is location in a zone;
3 3
C(x, t) is concentration at “t”, “x” in a zone (m /m );
3
Qv(t) is ventilation rate at “t” (m /h);
3 3
C (t) is average exhaust concentration at “t” (m /m ).
E
NOTE Formula (1) assumes that indoor-outdoor air density difference, mostly resulting from temperature
difference can be neglected.
3.2.2 2-point decay method
With the concentration in an effective mixed zone continuously made uniform, the time-mean air charge
rate is calculated from the measurement start point to the end point. It is not necessary for the specific
airflow rate to be constant during measuring.
The following equation is established from the above conditions.
Vt() =⋅VC(t)
gasemz
Ct()= Ct() (2)
E
where
3 3
C(t) is concentration in an effective mixed zone (uniform distribution) at t (m /m );
V
emz
is volume of an effective mixed zone (no time changes are assumed) [,= ∫∫∫ Cx tdV /]t
() ()
V C
E
3
(m ).
Formula (1) and Formula (2) provide Formula (3) to give Formula (4).
Qt
dC ()
t t
2 2
=− dt (3)
∫ ∫
t t
1 1
Ct
()
V
emz
C
1 ()
t
1
N = (4)
log
e
− C
()
tt t
21 2
where
t is time (t : Measurement start point, t : Measurement end point) (h);
1 2
Qt
()
1
t
2
is time-mean specific airflow rate ()= dt (1/h).
N ∫
t
− 1
tt
21 V
emz
Based on the measured concentration data of two different time points, the time-mean specific airflow
rate is calculated for that period. During the measurement period the concentration in the effective mixed
zone must be uniformly maintained. It is necessary for the accurate measuring of specific airflow rate
that the difference in concentration between the measurement start point and end point be sufficiently
greater than the concentration measurement error.
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SIST EN ISO 12569:2013
ISO 12569:2012(E)
3.2.3 Multipoint decay method
Specific airflow rate is calculated when the concentration distribution in an effective mixed zone is
maintained uniform and the ventilation rate does not fluctuate over time.
Formula (5) is obtained when the ventilation rate in Formula (3) is made constant and th
...
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