SIST EN ISO 23993:2011

Thermal insulation products for building equipment and industrial installations - Determination of design thermal conductivity (ISO 23993:2008, Corrected version 2009-10-01)

This International Standard gives methods to calculate design thermal conductivities from declared thermal conductivities for the calculation of the thermal performance of building equipment and industrial installations. These methods are valid for operating temperatures from -200 °C to +800 °C. The conversion factors, established for the different influences, are valid for the temperature ranges indicated in the relevant clauses or annexes.

Wärmedämmung an betriebstechnischen Anlagen in der Industrie und der technischen Gebäudeausrüstung - Bestimmung der Betriebswärmeleitfähigkeit (ISO 23993:2008, korrigierte Fassung 2009-10-01)

Diese Internationale Norm legt Verfahren zur Bestimmung von Betriebswärmeleitfähigkeiten aus Nennwerten der Wärmeleitfähigkeit für die Berechnung des wärmetechnischen Verhaltens von betriebstechnischen Anlagen fest. Diese Verfahren gelten für Betriebstemperaturen von −200 °C bis +800 °C. Die für die verschiedenen Einflüsse festgelegten Umrechnungsfaktoren gelten für die in den entsprechenden Abschnitten oder Anhängen angegebenen Temperaturbereiche.

Produits isolants thermiques pour l'équipement du bâtiment et les installations industrielles - Détermination de la conductivité thermique utile (ISO 23993:2008, Version corrigée 2009-10-01)

L'ISO 23993:2008 indique des méthodes de calcul de la conductivité thermique utile à partir de la conductivité thermique déclarée pour le calcul de la performance énergétique des équipements de bâtiments et des installations industrielles.
Ces méthodes s'appliquent pour des températures de service comprises entre -200 °C et +800 °C.
Les facteurs de conversion, déterminés pour les différentes influences, sont valables pour les plages de température indiquées dans les articles ou les annexes correspondants.

Toplotnoizolacijski proizvodi za opremo stavb in industrijske inštalacije - Določevanje projektne toplotne prevodnosti (ISO 23993:2008, popravljena različica 2009-10-01)

Ta mednarodni standard podaja metode za izračun projektne toplotne prevodnosti iz navedene toplotne prevodnosti za izračun toplotnega delovanja stavbne opreme in industrijskih inštalacij. Te metode veljajo za delovne temperature od –200 °C do +800 °C. Faktorji pretvorbe, vzpostavljeni za različne vplive, veljajo za temperaturne razpone, navedene v ustreznih klavzulah ali dodatkih.

General Information

• Status: Published
• Public Enquiry End Date: 08-Sep-2010
• Publication Date: 03-Feb-2011
• ICS: 27.220 - Heat recovery. Thermal insulation
• ICS: 91.100.60 - Thermal and sound insulating materials
• Technical Committee: TOP - Thermal insulation
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 02-Dec-2010
• Due Date: 06-Feb-2011
• Completion Date: 04-Feb-2011
• Directive: 89/106/EEC - Construction products
• Ref Project: EN ISO 23993:2010 - Thermal insulation products for building equipment and industrial installations - Determination of design thermal conductivity (ISO 23993:2008, Corrected version 2009-10-01)

Relations

• Replaces: SIST EN ISO 23993:2008 - Thermal insulation products for building equipment and industrial installations - Determination of design thermal conductivity (ISO 23993:2008)
• Effective Date: 01-Mar-2011
• Replaces: SIST EN ISO 23993:2008 - Thermal insulation products for building equipment and industrial installations - Determination of design thermal conductivity (ISO 23993:2008)
• Effective Date: 08-Jun-2022

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN ISO 23993:2011
01-marec-2011
Nadomešča:
SIST EN ISO 23993:2008
Toplotnoizolacijski proizvodi za opremo stavb in industrijske inštalacije -

Določevanje projektne toplotne prevodnosti (ISO 23993:2008, popravljena različica

2009-10-01)

Thermal insulation products for building equipment and industrial installations -

Determination of design thermal conductivity (ISO 23993:2008, Corrected version 2009-

10-01)
Wärmedämmung an betriebstechnischen Anlagen in der Industrie und der technischen
Gebäudeausrüstung - Bestimmung der Betriebswärmeleitfähigkeit (ISO 23993:2008,
korrigierte Fassung 2009-10-01)
Produits isolants thermiques pour l'équipement du bâtiment et les installations

industrielles - Détermination de la conductivité thermique utile (ISO 23993:2008, Version

corrigée 2009-10-01)
Ta slovenski standard je istoveten z: EN ISO 23993:2010
ICS:
27.220 Rekuperacija toplote. Heat recovery. Thermal
Toplotna izolacija insulation
91.100.60 Materiali za toplotno in Thermal and sound insulating
zvočno izolacijo materials
SIST EN ISO 23993:2011 en,fr,de

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

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SIST EN ISO 23993:2011
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SIST EN ISO 23993:2011
EUROPEAN STANDARD
EN ISO 23993
NORME EUROPÉENNE
EUROPÄISCHE NORM
November 2010
ICS 27.220; 91.120.10; 91.100.60 Supersedes EN ISO 23993:2008
English Version
Thermal insulation products for building equipment and industrial
installations - Determination of design thermal conductivity (ISO
23993:2008, Corrected version 2009-10-01)

Produits isolants thermiques pour l'équipement du bâtiment Wärmedämmung an betriebstechnischen Anlagen in der

et les installations industrielles - Détermination de la Industrie und der technischen Gebäudeausrüstung -

conductivité thermique utile (ISO 23993:2008, Version Bestimmung der Betriebswärmeleitfähigkeit (ISO

corrigée 2009-10-01) 23993:2008, korrigierte Fassung 2009-10-01)
This European Standard was approved by CEN on 11 October 2010.

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, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland,

Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.

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

© 2010 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 23993:2010: E

worldwide for CEN national Members.
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SIST EN ISO 23993:2011
EN ISO 23993:2010 (E)
Contents Page

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

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SIST EN ISO 23993:2011
EN ISO 23993:2010 (E)
Foreword

The text of ISO 23993:2008, Corrected version 2009-10-01 has been prepared by Technical Committee

ISO/TC 163 “Thermal performance and energy use in the built environment” of the International Organization

for Standardization (ISO) and has been taken over as EN ISO 23993:2010 by 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 May 2011, and conflicting national standards shall be withdrawn at the

latest by May 2011.

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 23993:2008.

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, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,

Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain,

Sweden, Switzerland and the United Kingdom.
Endorsement notice

The text of ISO 23993:2008, Corrected version 2009-10-01 has been approved by CEN as a EN ISO

23993:2010 without any modification.
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SIST EN ISO 23993:2011
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SIST EN ISO 23993:2011
INTERNATIONAL ISO
STANDARD 23993
First edition
2008-02-01
Corrected version
2009-10-01
Thermal insulation products for building
equipment and industrial installations —
Determination of design thermal
conductivity
Produits isolants thermiques pour l'équipement du bâtiment et les
installations industrielles — Détermination de la conductivité thermique
utile
Reference number
ISO 23993:2008(E)
ISO 2008
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SIST EN ISO 23993:2011
ISO 23993:2008(E)
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© ISO 2008

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

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Published in Switzerland
ii © ISO 2008 – All rights reserved
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SIST EN ISO 23993:2011
ISO 23993:2008(E)
Contents Page

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

Introduction ....................................................................................................................................................... vi

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

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

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

4 Symbols ................................................................................................................................................. 2

5 Determination of declared thermal conductivity ............................................................................... 2

6 Determination of the design value of thermal conductivity ............................................................. 3

7 Conversion of available data ............................................................................................................... 3

7.1 General................................................................................................................................................... 3

7.2 Conversion factor for temperature difference ................................................................................... 4

7.3 Conversion factor for moisture ........................................................................................................... 4

7.4 Conversion factor for ageing............................................................................................................... 5

7.5 Conversion factor for compression.................................................................................................... 5

7.6 Conversion factor for convection ....................................................................................................... 5

7.7 Conversion factor for thickness effect............................................................................................... 5

7.8 Conversion factor for regular joints ................................................................................................... 5

7.9 Additional thermal conductivity for regularly insulation-related thermal bridges,

e.g. spacers ........................................................................................................................................... 6

Annex A (normative) Conversion factors ........................................................................................................ 8

Annex B (informative) Examples of determination of the design thermal conductivity........................... 20

Annex C (informative) Approximate values of conversion factors ............................................................. 23

Bibliography ..................................................................................................................................................... 31

© ISO 2008 – All rights reserved iii
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SIST EN ISO 23993:2011
ISO 23993:2008(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 23993 was prepared by the European Committee for Standardization (CEN) Technical Committee

CEN/TC 89, Thermal performance of buildings and building components, in collaboration with ISO Technical

Committee ISO/TC 163, Thermal performance and energy use in the built environment, Subcommittee SC 2,

Calculation methods, in accordance with the Agreement on technical cooperation between ISO and CEN

(Vienna Agreement).

This International Standard is one of a series of standards on methods for the design and evaluation of the

thermal performance of building equipment and industrial installations.

This corrected version of ISO 23993:2008 incorporates the following corrections plus other minor editorial

modifications.
Clause 4: The following two rows have been added to the table:
N number of spacers per square metre —
∆λ thermal conductivity per spacer per square metre W/(m K)
Clause 6: Equations (1) and (2) have been re-inserted:
λ=+λλF∆ (1)
F =F F F F FFF (2)
ma c
∆θ C dj

7.9.2.2: The calculations have been modified as follows (i.e. with the substitution of ∆λ , the thermal

conductivity per spacer per square metre, for ∆λ i.e., with the deletion of “/spacers/m ” from the units):

Spacers of steel in the form of a flat bar
30 mm × 3 mm ∆λ = 0,003 5 W/(m·K)
40 mm × 4 mm ∆λ = 0,006 0 W/(m·K)
50 mm × 5 mm ∆λ = 0,008 5 W/(m·K)
iv © ISO 2008 – All rights reserved
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SIST EN ISO 23993:2011
ISO 23993:2008(E)

A new Equation (6) has been added to define the relationship between ∆λ and ∆λ and the original

Equation (6) renumbered to Equation (7).
7.9.3: The units “W(m·K)” have been corrected to “W/(m·K)”.

A.4.1 (twice) and A.4.2 (twice): The term “specific” has been added to the definition of W, “specific airflow

resistance.”

Annex B: The additional subtitles and introductory text, “B.1 Insulation materials” and “B.2 Conditions” have

been added. The line “Determination of the conversion factors and ∆λ” has been restyled as B.3 and

introductory text added.

Table C.1: The vertical line separating the subheadings “calcium-magnesium silicate fibre” and “calcium

silicate” and “microporous insulants” each from the subheading “Insulation” has been moved one column to

the left, i.e. from between the pictures for the two pipes to between the column “Application...” and the picture

of the horizontal pipe (consistent with other similar rows such as that for “mineral wool”).

Table C.1 (four times): The term “airflow resistance” has been replaced with the term “airflow resistivity”.

© ISO 2008 – All rights reserved v
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SIST EN ISO 23993:2011
ISO 23993:2008(E)
Introduction

The establishment of design values for thermal conductivity for the calculation of the thermal performance of

insulation systems for building equipment and industrial installations requires a consideration of various

possible influences affecting the thermal properties of the insulation products employed due to the operational

conditions of any individual insulation system.
Among these influences could be:

⎯ the non-linearity of the thermal conductivity curve over the temperature range in which the insulant may

be employed;
⎯ the thickness effect;
⎯ the effect of moisture in the insulant;
⎯ ageing effects, beyond those already incorporated in the declared value;
⎯ special installation effects such as single- or multi-layered installation.

In this International Standard, the conversion factors F, that need to be used in a variety of applications for a

variety of insulation products, are given and the principles and general equations as well as some guidance

for the establishment of design values for the calculation of the thermal performance of insulation systems are

described. The conversion factors valid for commonly employed insulation products are given in annexes.

They are well established in some cases and for some materials. Where experience is lacking and conversion

factors cannot be established accurately, they are given in the form of an “educated estimate” so that the

calculation result will be on the safe side, i.e. the calculated heat transfer will be greater than that actually

occurring when the calculation has obeyed the rules of this International Standard.

vi © ISO 2008 – All rights reserved
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SIST EN ISO 23993:2011
INTERNATIONAL STANDARD ISO 23993:2008(E)
Thermal insulation products for building equipment and
industrial installations — Determination of design thermal
conductivity
1 Scope

This International Standard gives methods to calculate design thermal conductivities from declared thermal

conductivities for the calculation of the thermal performance of building equipment and industrial installations.

These methods are valid for operating temperatures from −200 °C to +800 °C.

The conversion factors, established for the different influences, are valid for the temperature ranges indicated

in the relevant clauses or annexes.
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 7345, Thermal insulation — Physical quantities and definitions

ISO 8497, Thermal insulation — Determination of steady-state thermal transmission properties of thermal

insulation for circular pipes

ISO 9053, Acoustics — Material for acoustical applications — Determination of airflow resistance

ISO 9229, Thermal insulation — Vocabulary

ISO 13787, Thermal insulation products for building equipment and industrial installations — Determination of

declared thermal conductivity
3 Terms and definitions

For the purposes of this document, the terms and definitions given in ISO 7345, ISO 9229 and the following

apply.
3.1
declared thermal conductivity

value of the thermal conductivity of a material or product used for building equipment and industrial

installations:
⎯ based on measured data at reference conditions of temperature and humidity;

⎯ given as a limit value, in accordance with the determination method in ISO 13787;

⎯ corresponding to a reasonable expected service lifetime under normal conditions

© ISO 2008 – All rights reserved 1
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SIST EN ISO 23993:2011
ISO 23993:2008(E)
3.2
design thermal conductivity

value of thermal conductivity of an insulation material or product under specific external and internal

conditions which can be considered as typical of the performance of that material or product when

incorporated in a building equipment or industrial installation
4 Symbols
Symbol Quantity Unit
3 .
a compressibility coefficient m /(kg K)
D internal diameter of the layer m
d layer thickness m
d system thickness including air gap m
F overall conversion factor for thermal conductivity —
F ageing conversion factor —
F compression conversion factor —
F convection conversion factor —
F thickness conversion factor —
f thickness conversion coefficient —
F joint factor —
F moisture conversion factor —
3 3
f moisture conversion coefficient volume by volume m /m
F temperature difference conversion factor —
N number of spacers per square metre —
u moisture content mass by mass kg/kg
θ Celsius temperature °C
λ declared thermal conductivity W/(m K)
λ design thermal conductivity W/(m K)
λ integrated thermal conductivity W/(m K)
∆λ additional thermal conductivity due to thermal bridges, such as W/(m K)
spacers, which are regular parts of the insulation
∆λ thermal conductivity per spacer per square metre W/(m K)
ρ apparent density kg/m
3 3
ψ moisture content volume by volume m /m
5 Determination of declared thermal conductivity
Declared thermal conductivities shall be determined as given in ISO 13787.
2 © ISO 2008 – All rights reserved
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SIST EN ISO 23993:2011
ISO 23993:2008(E)

The product shall be described by its characteristics including a clear identification of the materials, the type

of facing if any, the structure, the blowing agent, the thickness and any other parameters having a possible

influence on thermal conductivity.

The declared thermal conductivity shall be determined either at a thickness large enough to neglect the

thickness effect or, for smaller thicknesses, based on measurements at those thicknesses.

6 Determination of the design value of thermal conductivity

The design value of thermal conductivity shall be determined from the declared thermal conductivity for the set

of conditions corresponding to the conditions of the expected application. Possible influences include the

following:

a) the average operating temperature, together with the hot and cold surface temperatures;

b) the average moisture content expected when the material is in equilibrium with a defined atmosphere

(temperature and relative humidity);

c) the ageing effect according to the application, if not included in the declared value;

d) the compression applied in the application;
e) the convection effect in the material;
f) the thickness effect;
g) the open joint effect;

h) the insulation-related thermal bridges, (thermal bridges that are regular part of the insulation system, e.g.

spacers), which are taken into account via a term ∆λ.
The design value of thermal conductivity shall be obtained either

⎯ from a declared thermal conductivity converted to the conditions of the application using Equation (1):

λ=+λλF∆ (1)

where the additional term ∆λ is obtained as given in 7.9 and the overall conversion factor F is given by:

F =F F F F FFF (2)
∆θ ma C c dj
⎯ or from values measured under application conditions.
NOTE Approximate values for F can be found in the informative Annex C.
7 Conversion of available data
7.1 General

Values of the different conversion factors for some insulating materials and operating conditions are given in

Annex A. Conversion factors derived from measured values according to the appropriate test methods, e.g.

EN 12667 or ISO 8497, may be used instead of the values in Annex A. If the material does not correspond to

the conditions for which the factors are given in Annex A, then the conversion factors derived from measured

values shall be used.
© ISO 2008 – All rights reserved 3
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SIST EN ISO 23993:2011
ISO 23993:2008(E)
7.2 Conversion factor for temperature difference

If the design thermal conductivity is requested at the same reference mean temperature and if the hot and

cold surface temperatures are the same as for the declared thermal conductivity, no conversion is needed

(F = 1).

In the case of thermal conductivity measurement made with the pipe tester (ISO 8497), no conversion is

needed when the measurement is carried out with the full temperature difference ∆θ.

If the design thermal conductivity is to be determined at another temperature from declared thermal

conductivities given in the form of a table of values at different temperatures, interpolation between values in

the table shall be based on the use of a best-fit equation such as a regression polynomial, of an order

sufficient to provide a correlation coefficient, r W 0,98.

If the design thermal conductivity is needed at the same reference mean temperature, but for another hot and

cold surface temperature difference, than that used for determining the declared thermal conductivity, the

conversion factor F shall be determined according to the procedure as given in A.1.

If the thermal conductivity measurement has been carried out with the full temperature difference, F = 1. If

the thermal conductivity measurement has been carried out with a ∆θ not exceeding 50 K, the procedure for

non-linearity applies.

If the design thermal conductivity is needed at another mean temperature than that of the declared thermal

conductivity and with another temperature difference, the procedures outlined above shall be followed

successively. As an alternative, the influence of the non-linearity of the thermal conductivity curve may be

taken into account by integrating the measured curve as given by Equation (3):
λ = λθ dθ (3)
θθ−
The temperature difference conversion factor is given by:
F = (4)
λ()θ
where (λ θ) is the value read on the curve at the reference temperature.
7.3 Conversion factor for moisture

The conversion factor F for volume-related moisture content shall be determined as follows:

f ψ −ψ
( )
ψ 21
F = e (5)
where
f is the moisture content conversion coefficient volume by volume;

ψ is the moisture content volume by volume for the determination of declared value of thermal

conductivity;
ψ is the moisture content volume by volume for the actual application.
The content of moisture in a given application shall be determined either
⎯ by measurements carried out in the conditions of the expected application, or
4 © ISO 2008 – All rights reserved
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SIST EN ISO 23993:2011
ISO 23993:2008(E)

⎯ by theoretical calculations using proven methods such as those given in ISO 15758 based on measured

values as described in ISO 12572, provided the assumptions on which they are based are met.

NOTE A possible test method to determine moisture content is given in EN 12088. If needed for the application, the

time period indicated in EN 12088 can be extended.
Some values of the coefficient f are given in A.2.
7.4 Conversion factor for ageing

The ageing depends upon the material type, facings, structures, the blowing agent, the temperature and the

thickness of the material. For a given material, the ageing effect can be obtained from theoretical models

validated by experimental data (see procedure in the product standard, where applicable).

No conversion is needed when the declared thermal conductivity or resistance already takes account of

ageing or when the ageing effect has been determined in conditions which do not significantly differ from the

design set of conditions.

If the set of conditions for the design thermal conductivities significantly differs from that in which the ageing

effect of the declared thermal conductivity has been determined, an ageing test in the set of conditions of the

design thermal conductivities shall be carried out.

If a conversion factor F is used, it shall allow for the calculation of the aged value of the thermal property

corresponding to a time not less than half the working lifetime of the product in the application concerned.

NOTE 1 The working lifetime for building equipment is often taken as 50 years.

NOTE 2 No conversion coefficients are given in this International Standard to derive the ageing conversion factor F .

No ageing conversion factor shall be used for mineral wool, ceramic fibre, calcium-magnesium silicate fibre,

calcium silicate, flexible elastomeric foam and cellular glass.
7.5 Conversion factor for compression

For compressible insulation products, the apparent density may change when the product is subject to load.

The influence on the thermal conductivity shall be taken into account by the factor F , which shall be

calculated as given in A.3.
7.6 Conversion factor for convection

The effect of convection in the case of vertical insulation layers shall be taken into account by a convection

factor F .
The factor F shall be calculated as given in A.4.
7.7 Conversion factor for thickness effect

For insulation materials permeable to radiation, the thermal conductivity changes with increasing thickness. If

the design thermal conductivity is needed at other thicknesses than those of the declared thermal conductivity,

the factor F shall be determined as given in A.5.
7.8 Conversion factor for regular joints

The influence of joints on the design thermal conductivity shall be addressed by the conversion factor F ,

which shall be calculated as given in A.6.

The conversion factor F shall be applied if the thermal conductivity has been measured in accordance with

ISO 8497, with a pipe tester having fewer joints than the actual application.
© ISO 2008 – All rights reserved 5
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SIST EN ISO 23993:2011
ISO 23993:2008(E)

7.9 Additional thermal conductivity for regularly insulation-related thermal bridges,

e.g. spacers
7.9.1 General

Components in the insulating layer which are regularly-spaced insulation-related thermal bridges like spacers

are taken into account by adding ∆λ to the corrected thermal conductivity λ of the installed insulation product

as given in Equation (1).

Plant-related and irregularly-spaced insulation-related thermal bridges, e.g. pipe mountings, supports,

armatures and frontal plates are thermal bridges which have to be considered as additional heat losses, e.g.

as described in ISO 12241.
7.9.2 Spacers
7.9.2.1 Spacers for sheet metal pipeline jackets

The additional thermal conductivity depends on a number of variables. The values indicated in the following

are approximate values and apply to comm
...

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Wärmedämmung an betriebstechnischen Anlagen in der Industrie und der technischen Gebäudeausrüstung - Bestimmung der Betriebswärmeleitfähigkeit (ISO 23993:2008, korrigierte Fassung 2009-10-01)Produits isolants thermiques pour l'équipement du bâtiment et les installations industrielles - Détermination de la conductivité thermique utile (ISO 23993:2008, Version corrigée 2009-10-01)Thermal insulation products for building equipment and industrial installations - Determination of design thermal conductivity (ISO 23993:2008, Corrected version 2009-10-01)91.100.60Thermal and sound insulating materials27.220Rekuperacija toplote. Toplotna izolacijaHeat recovery. Thermal insulationICS:Ta slovenski standard je istoveten z:EN ISO 23993:2010SIST EN ISO 23993:2011en,fr,de01-marec-2011SIST EN ISO 23993:2011SLOVENSKI

STANDARDSIST EN ISO 23993:20081DGRPHãþD
SIST EN ISO 23993:2011
EUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORM
EN ISO 23993

November 2010 ICS 27.220; 91.120.10; 91.100.60 Supersedes EN ISO 23993:2008English Version

Thermal insulation products for building equipment and industrial installations - Determination of design thermal conductivity (ISO 23993:2008, Corrected version 2009-10-01)

Produits isolants thermiques pour l'équipement du bâtiment et les installations industrielles - Détermination de la conductivité thermique utile (ISO 23993:2008, Version corrigée 2009-10-01)

Wärmedämmung an betriebstechnischen Anlagen in der Industrie und der technischen Gebäudeausrüstung - Bestimmung der Betriebswärmeleitfähigkeit (ISO 23993:2008, korrigierte Fassung 2009-10-01) This European Standard was approved by CEN on 11 October 2010.

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, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.

EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION EUROPÄISCHES KOMITEE FÜR NORMUNG
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B-1000 Brussels © 2010 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 23993:2010: ESIST EN ISO 23993:2011

EN ISO 23993:2010 (E) 2 Contents Page Foreword ..............................................................................................................................................................3 SIST EN ISO 23993:2011

EN ISO 23993:2010 (E) 3 Foreword The text of ISO 23993:2008, Corrected version 2009-10-01 has been prepared by Technical Committee ISO/TC 163 “Thermal performance and energy use in the built environment” of the International Organization for Standardization (ISO) and has been taken over as EN ISO 23993:2010 by 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 May 2011, and conflicting national standards shall be withdrawn at the latest by May 2011. 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 23993:2008. 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, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. Endorsement notice The text of ISO 23993:2008, Corrected version 2009-10-01 has been approved by CEN as a EN ISO 23993:2010 without any modification.

SIST EN ISO 23993:2011
SIST EN ISO 23993:2011
Reference numberISO 23993:2008(E)© ISO 2008

INTERNATIONAL STANDARD ISO23993First edition2008-02-01Corrected version2009-10-01 Thermal insulation products for building equipment and industrial installations — Determination of design thermal conductivity Produits isolants thermiques pour l'équipement du bâtiment et les installations industrielles — Détermination de la conductivité thermique utile

SIST EN ISO 23993:2011

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SIST EN ISO 23993:2011

ISO 23993:2008(E) © ISO 2008 – All rights reserved iiiContents Page Foreword............................................................................................................................................................iv Introduction.......................................................................................................................................................vi 1 Scope.....................................................................................................................................................1 2 Normative references...........................................................................................................................1 3 Terms and definitions...........................................................................................................................1 4 Symbols.................................................................................................................................................2 5 Determination of declared thermal conductivity...............................................................................2 6 Determination of the design value of thermal conductivity.............................................................3 7 Conversion of available data...............................................................................................................3 7.1 General...................................................................................................................................................3 7.2 Conversion factor for temperature difference...................................................................................4 7.3 Conversion factor for moisture...........................................................................................................4 7.4 Conversion factor for ageing...............................................................................................................5 7.5 Conversion factor for compression....................................................................................................5 7.6 Conversion factor for convection.......................................................................................................5 7.7 Conversion factor for thickness effect...............................................................................................5 7.8 Conversion factor for regular joints...................................................................................................5 7.9 Additional thermal conductivity for regularly insulation-related thermal bridges, e.g. spacers...........................................................................................................................................6 Annex A (normative)

Conversion factors........................................................................................................8 Annex B (informative)

Examples of determination of the design thermal conductivity...........................20 Annex C (informative)

Approximate values of conversion factors.............................................................23 Bibliography.....................................................................................................................................................31

SIST EN ISO 23993:2011

ISO 23993:2008(E) iv © ISO 2008 – All rights reserved 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 23993 was prepared by the European Committee for Standardization (CEN) Technical Committee CEN/TC 89, Thermal performance of buildings and building components, in collaboration with ISO Technical Committee ISO/TC 163, Thermal performance and energy use in the built environment, Subcommittee SC 2, Calculation methods, in accordance with the Agreement on technical cooperation between ISO and CEN (Vienna Agreement). This International Standard is one of a series of standards on methods for the design and evaluation of the thermal performance of building equipment and industrial installations. This corrected version of ISO 23993:2008 incorporates the following corrections plus other minor editorial modifications. Clause 4: The following two rows have been added to the table: N number of spacers per square metre —

∆λsq=thermal conductivity per spacer per square metre W/(m.K)

Clause 6: Equations (1) and (2) have been re-inserted: dF=+∆λλλ (1) macdjCFFFFFFFF∆θ= (2) 7.9.2.2: The calculations have been modified as follows (i.e. with the substitution of ∆λsq, the thermal conductivity per spacer per square metre, for ∆λ= i.e., with the deletion of “/spacers/m2” from the units): Spacers of steel in the form of a flat bar 30 mm × 3 mm ∆λsq = 0,003 5 W/(m·K) 40 mm × 4 mm ∆λsq = 0,006 0 W/(m·K) 50 mm × 5 mm ∆λsq= 0,008 5 W/(m·K) SIST EN ISO 23993:2011

ISO 23993:2008(E) © ISO 2008 – All rights reserved vA new Equation (6) has been added to define the relationship between ∆λ and ∆λsq and the original Equation (6) renumbered to Equation (7). 7.9.3: The units “W(m·K)” have been corrected to “W/(m·K)”. A.4.1 (twice) and A.4.2 (twice): The term “specific” has been added to the definition of W, “specific airflow resistance.” Annex B: The additional subtitles and introductory text, “B.1

Insulation materials” and “B.2

Conditions” have been added. The line “Determination of the conversion factors and ∆λ” has been restyled as B.3 and introductory text added. Table C.1: The vertical line separating the subheadings “calcium-magnesium silicate fibre” and “calcium silicate” and “microporous insulants” each from the subheading “Insulation” has been moved one column to the left, i.e. from between the pictures for the two pipes to between the column “Application...” and the picture of the horizontal pipe (consistent with other similar rows such as that for “mineral wool”). Table C.1 (four times): The term “airflow resistance” has been replaced with the term “airflow resistivity”. SIST EN ISO 23993:2011

ISO 23993:2008(E) vi © ISO 2008 – All rights reserved Introduction The establishment of design values for thermal conductivity for the calculation of the thermal performance of insulation systems for building equipment and industrial installations requires a consideration of various possible influences affecting the thermal properties of the insulation products employed due to the operational conditions of any individual insulation system. Among these influences could be: ⎯ the non-linearity of the thermal conductivity curve over the temperature range in which the insulant may be employed; ⎯ the thickness effect; ⎯ the effect of moisture in the insulant; ⎯ ageing effects, beyond those already incorporated in the declared value; ⎯ special installation effects such as single- or multi-layered installation. In this International Standard, the conversion factors F, that need to be used in a variety of applications for a variety of insulation products, are given and the principles and general equations as well as some guidance for the establishment of design values for the calculation of the thermal performance of insulation systems are described. The conversion factors valid for commonly employed insulation products are given in annexes. They are well established in some cases and for some materials. Where experience is lacking and conversion factors cannot be established accurately, they are given in the form of an “educated estimate” so that the calculation result will be on the safe side, i.e. the calculated heat transfer will be greater than that actually occurring when the calculation has obeyed the rules of this International Standard.

SIST EN ISO 23993:2011

INTERNATIONAL STANDARD ISO 23993:2008(E) © ISO 2008 – All rights reserved 1Thermal insulation products for building equipment and industrial installations — Determination of design thermal conductivity 1 Scope This International Standard gives methods to calculate design thermal conductivities from declared thermal conductivities for the calculation of the thermal performance of building equipment and industrial installations. These methods are valid for operating temperatures from −200 °C to +800 °C. The conversion factors, established for the different influences, are valid for the temperature ranges indicated in the relevant clauses or annexes. 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 7345, Thermal insulation — Physical quantities and definitions ISO 8497, Thermal insulation — Determination of steady-state thermal transmission properties of thermal insulation for circular pipes ISO 9053, Acoustics — Material for acoustical applications — Determination of airflow resistance ISO 9229, Thermal insulation — Vocabulary ISO 13787, Thermal insulation products for building equipment and industrial installations — Determination of declared thermal conductivity 3 Terms and definitions For the purposes of this document, the terms and definitions given in ISO 7345, ISO 9229 and the following apply. 3.1 declared thermal conductivity value of the thermal conductivity of a material or product used for building equipment and industrial installations: ⎯ based on measured data at reference conditions of temperature and humidity; ⎯ given as a limit value, in accordance with the determination method in ISO 13787; ⎯ corresponding to a reasonable expected service lifetime under normal conditions SIST EN ISO 23993:2011

ISO 23993:2008(E) 2 © ISO 2008 – All rights reserved 3.2 design thermal conductivity value of thermal conductivity of an insulation material or product under specific external and internal conditions which can be considered as typical of the performance of that material or product when incorporated in a building equipment or industrial installation 4 Symbols Symbol Quantity Unit aC compressibility coefficient m3/(kg.K) D internal diameter of the layer m d layer thickness m dg system thickness including air gap m F overall conversion factor for thermal conductivity — Fa ageing conversion factor — FC compression conversion factor — Fc convection conversion factor — Fd thickness conversion factor — fd thickness conversion coefficient — Fj joint factor — Fm moisture conversion factor — fψ moisture conversion coefficient volume by volume m3/m3 F∆θ temperature difference conversion factor — N number of spacers per square metre — u moisture content mass by mass kg/kg θ Celsius temperature °C λd declared thermal conductivity W/(m.K) λ design thermal conductivity W/(m.K) λ integrated thermal conductivity

W/(m.K) ∆λ additional thermal conductivity due to thermal bridges, such as spacers, which are regular parts of the insulation W/(m.K) ∆λsq=thermal conductivity per spacer per square metre W/(m.K) ρ apparent density kg/m3 ψ moisture content volume by volume m3/m3 5 Determination of declared thermal conductivity Declared thermal conductivities shall be determined as given in ISO 13787. SIST EN ISO 23993:2011

ISO 23993:2008(E) © ISO 2008 – All rights reserved 3The product shall be described by its characteristics including a clear identification of the materials, the type of facing if any, the structure, the blowing agent, the thickness and any other parameters having a possible influence on thermal conductivity. The declared thermal conductivity shall be determined either at a thickness large enough to neglect the thickness effect or, for smaller thicknesses, based on measurements at those thicknesses. 6 Determination of the design value of thermal conductivity The design value of thermal conductivity shall be determined from the declared thermal conductivity for the set of conditions corresponding to the conditions of the expected application. Possible influences include the following: a) the average operating temperature, together with the hot and cold surface temperatures; b) the average moisture content expected when the material is in equilibrium with a defined atmosphere (temperature and relative humidity); c) the ageing effect according to the application, if not included in the declared value; d) the compression applied in the application; e) the convection effect in the material; f) the thickness effect; g) the open joint effect; h) the insulation-related thermal bridges, (thermal bridges that are regular part of the insulation system, e.g. spacers), which are taken into account via a term ∆λ. The design value of thermal conductivity shall be obtained either ⎯ from a declared thermal conductivity converted to the conditions of the application using Equation (1): dF=+∆λλλ (1) where the additional term ∆ is obtained as given in 7.9 and the overall conversion factor F is given by: macdjCFFFFFFFF∆θ= (2) ⎯ or from values measured under application conditions. NOTE Approximate values for F can be found in the informative Annex C. 7 Conversion of available data 7.1 General Values of the different conversion factors for some insulating materials and operating conditions are given in Annex A. Conversion factors derived from measured values according to the appropriate test methods, e.g. EN 12667 or ISO 8497, may be used instead of the values in Annex A. If the material does not correspond to the conditions for which the factors are given in Annex A, then the conversion factors derived from measured values shall be used. SIST EN ISO 23993:2011

ISO 23993:2008(E) 4 © ISO 2008 – All rights reserved 7.2 Conversion factor for temperature difference If the design thermal conductivity is requested at the same reference mean temperature and if the hot and cold surface temperatures are the same as for the declared thermal conductivity, no conversion is needed (F∆θ = 1). In the case of thermal conductivity measurement made with the pipe tester (ISO 8497), no conversion is needed when the measurement is carried out with the full temperature difference ∆θ. If the design thermal conductivity is to be determined at another temperature from declared thermal conductivities given in the form of a table of values at different temperatures, interpolation between values in the table shall be based on the use of a best-fit equation such as a regression polynomial, of an order sufficient to provide a correlation coefficient, r W 0,98. If the design thermal conductivity is needed at the same reference mean temperature, but for another hot and cold surface temperature difference, than that used for determining the declared thermal conductivity, the conversion factor F∆θ shall be determined according to the procedure as given in A.1. If the thermal conductivity measurement has been carried out with the full temperature difference, F∆θ = 1. If the thermal conductivity measurement has been carried out with a ∆θ not exceeding 50 K, the procedure for non-linearity applies. If the design thermal conductivity is needed at another mean temperature than that of the declared thermal conductivity and with another temperature difference, the procedures outlined above shall be followed successively. As an alternative, the influence of the non-linearity of the thermal conductivity curve may be taken into account by integrating the measured curve as given by Equation (3): ()21211dθθλλθθθθ=−∫ (3) The temperature difference conversion factor is given by: ()Fθλλθ∆= (4) where ()λθ is the value read on the curve at the reference temperature. 7.3 Conversion factor for moisture The conversion factor Fm for volume-related moisture content shall be determined as follows: ()21mefFψψψ−= (5) where fψ is the moisture content conversion coefficient volume by volume; ψ1 is the moisture content volume by volume for the determination of declared value of thermal conductivity; ψ2 is the moisture content volume by volume for the actual application. The content of moisture in a given application shall be determined either ⎯ by measurements carried out in the conditions of the expected application, or SIST EN ISO 23993:2011

ISO 23993:2008(E) © ISO 2008 – All rights reserved 5⎯ by theoretical calculations using proven methods such as those given in ISO 15758 based on measured values as described in ISO 12572, provided the assumptions on which they are based are met. NOTE A possible test method to determine moisture content is given in EN 12088. If needed for the application, the time period indicated in EN 12088 can be extended. Some values of the coefficient fψ are given in A.2. 7.4 Conversion factor for ageing The ageing depends upon the material type, facings, structures, the blowing agent, the temperature and the thickness of the material. For a given material, the ageing effect can be obtained from theoretical models validated by experimental data (see procedure in the product standard, where applicable). No conversion is needed when the declared thermal conductivity or resistance already takes account of ageing or when the ageing effect has been determined in conditions which do not significantly differ from the design set of conditions. If the set of conditions for the design thermal conductivities significantly differs from that in which the ageing effect of the declared thermal conductivity has been determined, an ageing test in the set of conditions of the design thermal conductivities shall be carried out. If a conversion factor Fa is used, it shall allow for the calculation of the aged value of the thermal property corresponding to a time not less than half the working lifetime of the product in the application concerned. NOTE 1 The working lifetime for building equipment is often taken as 50 years. NOTE 2 No conversion coefficients are given in this International Standard to derive the ageing conversion factor Fa. No ageing conversion factor shall be used for mineral wool, ceramic fibre, calcium-magnesium silicate fibre, calcium silicate, flexible elastomeric foam and cellular glass. 7.5 Conversion factor for compression For compressible insulation products, the apparent density may change when the product is subject to load. The influence on the thermal conductivity shall be taken into account by the factor FC, which shall be calculated as given in A.3. 7.6 Conversion factor for convection The effect of convection in the case of vertical insulation layers shall be taken into account by a convection factor Fc. The factor Fc shall be calculated as given in A.4. 7.7 Conversion factor for thickness effect For insulation materials permeable to radiation, the thermal conductivity changes with increasing thickness. If the design thermal conductivity is needed at other thicknesses than those of the declared thermal conductivity, the factor Fd shall be determined as given in A.5. 7.8 Conversion factor for regular joints The influence of joints on the design thermal conductivity shall be addressed by the conversion factor Fj, which shall be calculated as given in A.6. The conversion factor Fj shall be applied if the thermal conductivity has been measured in accordance with ISO 8497, with a pipe tester having fewer joints than the actual application. SIST EN ISO 23993:2011

ISO 23993:2008(E) 6 © ISO 2008 – All rights reserved 7.9 Additional thermal conductivity for regularly insulation-related thermal bridges, e.g. spacers 7.9.1 General Components in the insulating layer which are regularly-spaced insulation-related thermal bridges like spacers are taken into account by adding ∆λ to the corrected thermal conductivity λd of the installed insulation product as given in Equation (1). Plant-related and irregularly-spaced insulation-related thermal bridges, e.g. pipe mountings, supports, armatures and frontal plates are thermal bridges which have to be considered as additional heat losses, e.g. as described in ISO 12241. 7.9.2 Spacers 7.9.2.1 Spacers for sheet metal pipeline jackets The additional thermal conductivity depends on a number of variables. The values indicated in the following are approximate values and apply to common insulating layer thicknesses from 100 mm to 300 mm and common insulation systems for heat protection. NOTE 1 Reference [9] in the Bibliography provides possible procedures for special insulation systems. Additions to thermal conductivity for steel spacers ∆λ = 0,010 W/(m·K) for austenitic steel spacers ∆λ = 0,004 W/(m·K) for ceramic spacers ∆λ = 0,003 W/(m·K) NOTE 2 These values can be used in the range of 50 mm to 200 mm, see Reference [10]. 7.9.2.2 Spacers for sheet metal jackets for walls Spacers of steel in the form of a flat bar 30 mm × 3 mm ∆λsq = 0,003 5 W/(m·K) 40 mm × 4 mm ∆λsq = 0,006 0 W/(m·K) 50 mm × 5 mm ∆λsq= 0,008 5 W/(m·K) Additions ∆λ to thermal conductivity to account for spacers for sheet metal jackets for walls depend on the number of spacers per square metre (m2). The total addition is calculated by: sqNλλ∆=∆ (6) where N is the number of spacers per square metre (m2); ∆λsq is the thermal conductivity per spacer per square metre. SIST EN ISO 23993:2011

ISO 23993:2008(E) © ISO 2008 – All rights reserved 77.9.3 Mechanical fasteners penetrating an insulation layer Additions ∆λ to thermal conductivity to account for fasteners depend on the number of fasteners per square metre (m2) and on the geometry. The total addition is calculated by: inλλ∆=∆ (7) where ∆λi is the additional conductivity due to fastener i (i = 1 … n). For steel fasteners, diameter 4 mm, 9 fasteners/m2: ∆λ = 0,006 W/(m⋅K). For austenitic steel fasteners, diameter 4 mm, 9 fasteners/m2: ∆λ = 0,004 W/(m⋅K). SIST EN ISO 23993:2011

ISO 23993:2008(E) 8 © ISO 2008 – All rights reserved Annex A (normative)

Conversion factors A.1 Conversion factors for the influence of the non-linearity of the thermal conductivity versus temperature curve When not using directly integrated values for the thermal co

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