ISO 18782:2023

Textiles — Determination of dynamic hygroscopic heat generation

This document specifies a test method for the determination of hygroscopic heat generated by flowing low to high humidity air on one side of a surface. It is applicable to all kinds of sheet-shaped textile materials.

Textiles — Détermination de la production de chaleur dynamique hygroscopique

Le présent document définit une méthode d’essai pour déterminer la production de chaleur hygroscopique par application d’un flux d’air de faible humidité suivi d’un flux d’air d’humidité élevée sur une face d’une surface. Il est applicable à tous types de matériaux textiles plats.

General Information

• Status: Published
• Publication Date: 21-May-2023
• ICS: 59.080.01 - Textiles in general
• Technical Committee: ISO/TC 38 - Textiles
• Drafting Committee: ISO/TC 38 - Textiles
• Current Stage: 6060 - International Standard published
• Start Date: 22-May-2023
• Due Date: 25-Feb-2023
• Completion Date: 22-May-2023

Relations

• Revises: ISO 18782:2015 - Textiles — Determination of dynamic hygroscopic heat generation
• Effective Date: 06-Jun-2022

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 18782
Second edition
2023-05
Textiles — Determination of dynamic
hygroscopic heat generation
Textiles — Détermination de la production de chaleur dynamique
hygroscopique
Reference number
ISO 18782:2023(E)
© ISO 2023

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ISO 18782:2023(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2023
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
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
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ISO 18782:2023(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 2
5 Testing condition . 2
5.1 Low humidity air . 2
5.2 High humidity air . 2
6 Reagents and materials . 2
7 Apparatus . 2
8 Conditioning atmosphere for sampling . 6
9 Preparation of specimens .6
10 Test procedure .6
10.1 Mounting of test specimens . 6
10.2 Pretreatment process immediately before measurement . 6
10.3 Measurement process . 6
11 Calculation . 7
12 Test report . 8
Annex A (normative) Determination of the air flow rate for high humidity air .9
Annex B (informative) Interlaboratory test results .11
Annex C (informative) Example of a practical testing apparatus .15
Annex D (informative) Example of an interpretation of the test result .16
Bibliography .17
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ISO 18782:2023(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 document 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).
ISO draws attention to the possibility that the implementation of this document may involve the use
of (a) patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed
patent rights in respect thereof. As of the date of publication of this document, ISO had received notice of
(a) patent(s) which may be required to implement this document. However, implementers are cautioned
that this may not represent the latest information, which may be obtained from the patent database
available at www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent
rights.
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, 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
www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 38, Textiles.
This second edition cancels and replaces the first edition (ISO 18782:2015), which has been technically
revised.
The main changes are as follows:
— in Clause 3, temperature definitions have been added;
— in Clause 7, Figure 1 has been changed from one testing position to 4 testing positions;
— in 7.2.5.5, rectifying plate was introduced for more stable testing;
— in Clause 10.2, the pretreatment process has been added;
— in Annex A, the pretreatment process has been added to the testing method for the determination
of air flow rate for high humidity.
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.
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ISO 18782:2023(E)
Introduction
In the apparel and clothing market, warm heat-comfort textile material is attracting consumers'
attention. It offers comfortable warmth through the combined technology of the hygroscopic heat
generation and heat insulation.
The phenomenon of the hygroscopic heat generation is known as a common function of natural fibres
especially, but not so much for synthetic fibres. Therefore, the synthetic fibre producers have been
developing fibres and textiles with an appropriate warm-feeling property.
This document provides a test method to obtain the practical heat generation of textiles under wearing
conditions.
The apparatus used in this test method has multiple test positions. So, this method is practical and
economical with high accuracy.
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INTERNATIONAL STANDARD ISO 18782:2023(E)
Textiles — Determination of dynamic hygroscopic heat
generation
1 Scope
This document specifies a test method for the determination of hygroscopic heat generated by flowing
low to high humidity air on one side of a surface. It is applicable to all kinds of sheet-shaped textile
materials.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements 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 105-F02, Textiles — Tests for colour fastness — Part F02: Specification for cotton and viscose adjacent
fabrics
ISO 139, Textiles — Standard atmospheres for conditioning and testing
ISO 3696, Water for analytical laboratory use — Specification and test methods
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
generated hygroscopic heat
hygroscopic heat generated by the loss of kinetic energy when gaseous water molecules are adsorbed
on a surface of textile material
3.2
temperature at low humidity
T
initial
initial equilibrium temperature at measurement side of a specimen when the low humidity air is
supplied
3.3
generated hygroscopic heat temperature
ΔT
temperature difference between the initial equilibrium temperature and the temperature when the
high humidity air is supplied on measurement side of a specimen
3.4
maximum temperature at high humidity
T
max
maximum temperature at measurement side of a specimen when high humidity air is supplied
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ISO 18782:2023(E)
3.5
maximum generated hygroscopic heat temperature
ΔT
max
maximum value of the generated hygroscopic heat temperature ΔT
4 Principle
When the air supply is switched from low humidity to high humidity in instant, the temperature at the
specimen increases and reaches a peak due to the hygroscopic heat generation. The temperature at one
side of specimen is measured during this air change and the peak temperature is determined as ΔT .
max
In this test method, the high humidity air flow rate is determined by a cotton control specimen in which
the ΔT becomes 2,8 °C ± 0,3 °C.
max
5 Testing condition
5.1 Low humidity air
The air is taken from the atmosphere of the constant temperature and humidity chamber (7.1) in which
the temperature is controlled at 20 °C ± 2 °C and the relative humidity at (40 ± 3) %. The air flow rate is
set at 1,0 l/min ± 0,1 l/min.
5.2 High humidity air
The air in the constant temperature and humidity chamber (7.1) is passed through bubbling bottle
(7.2.2) and supplied to specimen as a high humidity air.
NOTE High humidity air is controlled by the air flow rate only; therefore, humidity measurements are not
essential. However, the humidity of high humidity air has been known as (90 ± 5) % RH.
6 Reagents and materials
6.1 Water, distilled water, ion exchanged water, grade 3 water according to ISO 3696 or equivalent
for humidifying air in a bubbling bottle (7.2.2).
6.2 Control specimen, a cotton adjacent fabric as specified in ISO 105-F02.
7 Apparatus
7.1 Constant temperature and humidity chamber or room, capable of maintaining the
temperature at 20 °C ± 2 °C and the relative humidity at (40 ± 3) %. The hygroscopic heat generation
testing apparatus (7.2) is placed in the chamber or room.
7.2 Hygroscopic heat generation testing apparatus, shown in Figure 1. All devices are placed in
the chamber (7.1) in case of cabin type. If in case the oven type, the switching valve and control device
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ISO 18782:2023(E)
(7.2.3) and monitoring recorder (7.3) are placed in the outside of the chamber. Air is supplied from one
air supply path to four measuring units. An example of practical testing apparatus is shown in Annex C.
Key
Key
1 specimen 10 air bubbling bottle with water
2 specimen holder 11, 12 switching valve
3 specimen table 13, 14 flow control valve
4 air lid 15 humidity sensor
5 rectifying plate 16 air supply path
6 thermometer 17 control device
7 flowmeter with regulating valve 18 monitoring recorder
8 measuring units 19 constant temperature and humidity chamber
9 air pump
Figure 1 — Schematic diagram of the testing apparatus
7.2.1 Air pump, capable of collecting air from the atmosphere of the chamber (7.1) and supplying air
to the specimen at a rate of 1,0 l/min ± 0,1 l/min.
7.2.2 Bubbling bottle, consisting of an air-tight bottle with an air inlet tube attached to a porous
cylinder such as air stones to make fine air bubbles and with air outlet tube to collect high humidity air
after bubbling. Completely submerge the porous cylinder in water during testing.
7.2.3 Switching valve with control device, used for switching to low humidity air path (11, 13, 12
and 15 in Figure 1) or high humidity air path (11, 14, 12 and 15 in Figure 1) passed through a bubbling
bottle (10 in Figure 1 and 7.2.2).
7.2.4 Humidity sensor, used for detecting a humidity of air supply path, from 5 % RH to 100 % RH,
with accuracy ±5 % RH.
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ISO 18782:2023(E)
7.2.5 Measuring units and rectifying plate, four measuring units (as shown in Figure 1) where each
unit consists of: a specimen table (7.2.5.1), a specimen holder (7.2.5.2), a thermometer (7.2.5.3), and a
flowmeter with regulating valve (7.2.5.4). Each measuring unit is positioned as shown in Figure 2, and
a rectifying plate (7.2.5.5) is stacked to cover the entire measuring part.
7.2.5.1 Specimen table, consisting of a board of polystyrene foam with a square of 50 mm± 5 mm,
a thickness of 7 mm ± 2 mm and 4 air holes with a diameter of 5,0 mm ± 0,3 mm each. The holes are
located 10 mm from the centre of the table
...

NORME ISO
INTERNATIONALE 18782
Deuxième édition
2023-05
Textiles — Détermination de la
production de chaleur dynamique
hygroscopique
Textiles — Determination of dynamic hygroscopic heat generation
Numéro de référence
ISO 18782:2023(F)
© ISO 2023

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ISO 18782:2023(F)
DOCUMENT PROTÉGÉ PAR COPYRIGHT
© ISO 2023
Tous droits réservés. Sauf prescription différente ou nécessité dans le contexte de sa mise en œuvre, aucune partie de cette
publication ne peut être reproduite ni utilisée sous quelque forme que ce soit et par aucun procédé, électronique ou mécanique,
y compris la photocopie, ou la diffusion sur l’internet ou sur un intranet, sans autorisation écrite préalable. Une autorisation peut
être demandée à l’ISO à l’adresse ci-après ou au comité membre de l’ISO dans le pays du demandeur.
ISO copyright office
Case postale 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Genève
Tél.: [phone]
E-mail: [e-mail]
Web: www.iso.org
Publié en Suisse
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ISO 18782:2023(F)
Sommaire Page
Avant-propos .iv
Introduction .v
1 Domaine d’application . 1
2 Références normatives .1
3 Termes et définitions . 1
4 Principe. 2
5 Conditions d’essai . 2
5.1 Air de faible humidité . 2
5.2 Air d’humidité élevée . 2
6 Réactifs et matériaux . 2
7 Appareillage . 2
8 Atmosphère de conditionnement pour l’échantillonnage . 6
9 Préparation des éprouvettes . 6
10 Mode opératoire d’essai .6
10.1 Montage des éprouvettes d’essai . 6
10.2 Traitement préalable juste avant le mesurage . 6
10.3 Processus de mesure . 6
11 Calcul . 8
12 Rapport d’essai . 8
Annexe A (normative) Détermination du débit d’air pour l’air d’humidité élevée .9
Annexe B (informative) Résultats de l’essai interlaboratoires .11
Annexe C (informative) Exemple d’appareillage d’essai pratique .15
Annexe D (informative) Exemple d’interprétation du résultat d’essai.16
Bibliographie .17
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ISO 18782:2023(F)
Avant-propos
L'ISO (Organisation internationale de normalisation) est une fédération mondiale d'organismes
nationaux de normalisation (comités membres de l'ISO). L'élaboration des Normes internationales est
en général confiée aux comités techniques de l'ISO. Chaque comité membre intéressé par une étude
a le droit de faire partie du comité technique créé à cet effet. Les organisations internationales,
gouvernementales et non gouvernementales, en liaison avec l'ISO participent également aux travaux.
L'ISO collabore étroitement avec la Commission électrotechnique internationale (IEC) en ce qui
concerne la normalisation électrotechnique.
Les procédures utilisées pour élaborer le présent document et celles destinées à sa mise à jour sont
décrites dans les Directives ISO/IEC, Partie 1. Il convient, en particulier, de prendre note des différents
critères d'approbation requis pour les différents types de documents ISO. Le présent document a
été rédigé conformément aux règles de rédaction données dans les Directives ISO/IEC, Partie 2 (voir
www.iso.org/directives).
L’ISO attire l’attention sur le fait que la mise en application du présent document peut entraîner
l’utilisation d’un ou de plusieurs brevets. L’ISO ne prend pas position quant à la preuve, à la validité
et à l’applicabilité de tout droit de brevet revendiqué à cet égard. À la date de publication du présent
document, l’ISO avait reçu notification qu’un ou plusieurs brevets pouvaient être nécessaires à sa
mise en application. Toutefois, il y a lieu d’avertir les responsables de la mise en application du présent
document que des informations plus récentes sont susceptibles de figurer dans la base de données de
brevets, disponible à l'adresse www.iso.org/brevets. L’ISO ne saurait être tenue pour responsable de ne
pas avoir identifié tout ou partie de tels droits de propriété.
Les appellations commerciales éventuellement mentionnées dans le présent document sont données
pour information, par souci de commodité, à l’intention des utilisateurs et ne sauraient constituer un
engagement.
Pour une explication de la nature volontaire des normes, la signification des termes et expressions
spécifiques de l'ISO liés à l'évaluation de la conformité, ou pour toute information au sujet de l'adhésion
de l'ISO aux principes de l’Organisation mondiale du commerce (OMC) concernant les obstacles
techniques au commerce (OTC), voir www.iso.org/avant-propos.
Le présent document a été élaboré par le comité technique ISO/TC 38, Textiles.
Cette deuxième édition annule et remplace la première édition (ISO 18782:2015), qui a fait l’objet d’une
révision technique.
Les principales modifications sont les suivantes :
— à l’Article 3, les définitions des températures ont été ajoutées ;
— à l’Article 7, un emplacement d’essai est remplacé par 4 emplacements d’essai sur la Figure 1 ;
— en 7.2.5.5, la plaque de rectification a été introduite pour des conditions d’essai plus stables ;
— en 10.2, le traitement préalable a été ajoutée ;
— à l’Annexe A, le traitement préalable par essai a été ajouté à la méthode d’essai pour la détermination
du débit d’air pour l’air d’humidité élevée.
Il convient que l’utilisateur adresse tout retour d’information ou toute question concernant le présent
document à l’organisme national de normalisation de son pays. Une liste exhaustive desdits organismes
se trouve à l’adresse www.iso.org/fr/members.html.
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ISO 18782:2023(F)
Introduction
Sur le marché des vêtements et de l’habillement, le consommateur porte une attention particulière aux
matières textiles offrant un confort thermique. Ces matières procurent une chaleur agréable obtenue
en combinant les technologies de production de chaleur hygroscopique et d’isolation thermique.
Le phénomène de production de chaleur hygroscopique est connu comme étant une fonction courante
des fibres naturelles en particulier, ce qui est moins le cas des fibres synthétiques. Par conséquent, les
producteurs de fibres synthétiques ont développé des fibres et des textiles possédant des propriétés
appropriées pour offrir une sensation de chaleur.
Le présent document est une méthode d’essai qui permet de déterminer la production de chaleur des
textiles dans la pratique, lorsqu’ils sont portés.
L’appareillage utilisé pour la présente méthode d’essai comporte plusieurs emplacements d’essai. Cette
méthode d’essai s’avère donc pratique et économique, tout en offrant une précision élevée.
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NORME INTERNATIONALE ISO 18782:2023(F)
Textiles — Détermination de la production de chaleur
dynamique hygroscopique
1 Domaine d’application
Le présent document définit une méthode d’essai pour déterminer la production de chaleur
hygroscopique par application d’un flux d’air de faible humidité suivi d’un flux d’air d’humidité élevée
sur une face d’une surface. Il est applicable à tous types de matériaux textiles plats.
2 Références normatives
Les documents suivants sont cités dans le texte de sorte qu’ils constituent, pour tout ou partie de leur
contenu, des exigences du présent document. Pour les références datées, seule l’édition citée s’applique.
Pour les références non datées, la dernière édition du document de référence s'applique (y compris les
éventuels amendements).
ISO 105-F02, Textiles — Essais de solidité des teintures — Partie F02: Spécifications pour les tissus témoins
en coton et en viscose
ISO 139, Textiles — Atmosphères normales de conditionnement et d'essai
ISO 3696, Eau pour laboratoire à usage analytique — Spécification et méthodes d'essai
3 Termes et définitions
Pour les besoins du présent document, les termes et définitions suivants s’appliquent.
L’ISO et l’IEC tiennent à jour des bases de données terminologiques destinées à être utilisées en
normalisation, consultables aux adresses suivantes:
— ISO Online browsing platform: disponible à l’adresse https:// www .iso .org/ obp
— IEC Electropedia: disponible à l’adresse https:// www .electropedia .org/
3.1
production de chaleur hygroscopique
chaleur hygroscopique produite par la perte d’énergie cinétique lorsque des molécules d’eau gazeuse
sont adsorbées à la surface d’une matière textile
3.2
température à faible humidité
T
initiale
température d’équilibre initiale sur la face de mesure d’une éprouvette lorsque de l’air de faible humidité
est appliqué
3.3
température de production de chaleur hygroscopique
ΔT
différence de température entre la température d’équilibre initiale et la température lorsque de l’air
d’humidité élevée est appliqué sur la face de mesure d’une éprouvette
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ISO 18782:2023(F)
3.4
température maximale à humidité élevée
T
max
température maximale sur la face de mesure d’une éprouvette lorsque de l’air d’humidité élevée est
appliqué
3.5
température maximale de production de chaleur hygroscopique
ΔT
max
valeur maximale de la température de production de chaleur hygroscopique ΔT
4 Principe
Lorsque l’alimentation en air passe instantanément d’une faible humidité à une humidité élevée, la
température au niveau de l’éprouvette augmente et atteint un maximum en raison de la production
de chaleur hygroscopique. La température sur une face de l’éprouvette est mesurée pendant ce
changement d’air et la température maximale ΔT est déterminée. Dans cette méthode d’essai, le
max
débit d’air d’humidité élevée est déterminé par une éprouvette témoin en coton pour laquelle ΔT
max
s’élève à 2,8 °C ± 0,3 °C.
5 Conditions d’essai
5.1 Air de faible humidité
L’air est prélevé de l’atmosphère de l’enceinte à température et humidité constantes (7.1) dans laquelle
la température est maîtrisée à 20 °C ± 2 °C et l’humidité relatif à (40 ± 3) %. Le débit d’air est réglé
à 1,0 l/min ± 0,1 l/min.
5.2 Air d’humidité élevée
L’air dans l’enceinte à température et humidité constantes (7.1) passe dans un flacon de barbotage (7.2.2)
et est appliqué à l’éprouvette sous forme d’air d’humidité élevée.
NOTE L’air d’humidité élevée est maîtrisé par le débit d’air uniquement ; les mesures de l’humidité ne sont
donc pas essentielles. Cependant, il est généralement admis que l’humidité de l’air d’humidité élevée se situe
à (90 ± 5) % HR.
6 Réactifs et matériaux
6.1 Eau, eau distillée, eau par échange d’ions, eau de qualité 3 conformément à l’ISO 3696 ou
équivalent pour l’humidification de l’air dans un flacon de barbotage (7.2.2).
6.2 Éprouvette témoin, tissu témoin en coton tel que spécifié dans l’ISO 105-F02.
7 Appareillage
7.1 Enceinte ou pièce à température et humidité constantes, pouvant maintenir la température
à 20 °C ± 2 °C et l’humidité relatif à (40 ± 3) %. L’appareillage pour l’essai de production de chaleur
hygroscopique (7.2) est placé dans l’enceinte ou la pièce.
7.2 Appareillage pour l’essai de production de chaleur hygroscopique, illustré à la Figure 1. Tous
les dispositifs sont placés dans l’enceinte (7.1) dans le cas du type cabine. Pour le type étuve, la vanne
de commutation, le dispositif de commande (7.2.3) et l’enregistreur de surveillance (7.3) sont placés à
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ISO 18782:2023(F)
l’extérieur de l’enceinte. Une conduite d’arrivée d’air alimente en air quatre blocs de mesure. Un exemple
d’appareillage d’essai pratique dans l’Annexe C.
Légende
1 éprouvette 10 flacon de barbotage de l’air dans de l’eau
2 dispositif de maintien de l’éprouvette 11, 12 vanne de commutation
3 table pour éprouvettes 13, 14 vanne de réglage de débit
4 couvercle à air 15 capteur d’humidité
5 plaque de rectification 16 conduite d’arrivée d’air
6 thermomètre 17 dispositif de commande
7 débitmètre avec vanne de réglage 18 enregistreur de surveillance
8 blocs de mesure 19 enceinte à température et humidité constantes
9 pompe à air
Figure 1 — Représentation schématique de l’appareillage d’essai
7.2.1 Pompe à air, pouvant prélever l’air de l’atmosphère de l’enceinte (7.1) et l’introduire sur
l’éprouvette à un débit de 1,0 l/min ± 0,1 l/min.
7.2.2 Flacon de barbotage, constitué d’un flacon hermétique à l’air équipé d’un tube d’entrée d’air
fixé à un cylindre poreux, tel que des pierres à air pour produire de fines bulles d’air, ainsi que d’un
tube de sortie d’air pour recueillir l’air d’humidité élevée après le barbotage. Immerger complètement le
cylindre poreux dans l’eau pendant l’essai.
7.2.3 Vanne de commutation avec dispositif de commande, utilisée pour commuter entre la
conduite d’air de faible humidité (11, 13, 12 et 15 à la Figure 1) et la conduite d’air d’humidité élevée (11,
14, 12 et 15 à la Figure 1) en passant par un flacon de barbotage (10 à la Figure 1 et 7.2.2).
7.2.4 Capteur d’humidité, utilisé pour mesurer l’humidité de la conduite d’arrivée d’air entre 5 % HR
et 100 % HR, avec une tolérance de ±5 % HR.
7.2.5 Blocs de mesure et plaque de rectification, quatre blocs de mesure (comme illustré à
la Figure 1) composés chacun de : une table pour éprouvettes (7.2.5.1), un dispositif de maintien de
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ISO 18782:2023(F)
l’éprouvette (7.2.5.2), un thermomètre (7.2.5.3) et un débitmètre avec vanne de réglage (7.2.5.4).
Chaque bloc de mesure est placé comme illustré à la Figure 2 et une plaque de rectification (7.2.5.5) est
ajoutée pour recouvrir tout le système de mesure.
7.2.5.1 Table pour éprouvettes, constituée d’un panneau en mousse de polystyrène de forme
carrée de 50 mm ± 5 mm de côté et de 7 mm ± 2 mm d’épaisseur et de 4 orifices de passage d’air
de 5,0 mm ± 0,3 mm de diamètre chacun. Les orifices sont situés à 10 mm du centre de la table sur les
diagonales du carré.
EXEMPLE Par exemple, de la mousse de polystyrène ayant une conductivité thermique de 0,035 W/m K peut
être utilisée comme matériau d’isolation.
Légende
1 éprouvette 6 thermomètre
2 dispositif de maintien de l’éprouvette 7 débitmètre avec vanne de réglage
3 table pour éprouvettes 8 orifices de passage de l’air
4 couvercle à air 9 débit d’air
5 plaque de rectification
Figure 2 — Bloc de mesure et plaque de re
...

ISO/DISFDIS 18782:2023(E)
Second edition
2022-11-01
2023-02-06
ISO TC 38/SC /WG 27
Secretariat: SAC
Textiles — Determination of dynamic hygroscopic heat generation

---------------------- Page: 1 ----------------------
ISO/FDIS 18782:2023(E)
© ISO 20222023
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
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Email: [e-mail]
Website: www.iso.orgwww.iso.org
Published in Switzerland
ii © ISO 2023 – All rights reserved

---------------------- Page: 2 ----------------------
ISO/FDIS 18782:2023(E)
Contents
Foreword . v
Introduction . vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 2
6 Reagents and materials . 2
7 Apparatus . 2
8 Conditioning atmosphere for sampling . 8
9 Preparation of specimens . 8
10 Test procedure . 8
11 Calculation . 11
12 Test report . 11
Annex A (normative) Determination of the air flow rate for high humidity air . 12
A.1 General . 12
A.2 Procedure . 12
A.3 Repetition and determination . 12
© ISO 2023 – All rights reserved iii

---------------------- Page: 3 ----------------------
ISO/FDIS 18782:2023(E)
Annex B (informative) Interlaboratory test results . 15
B.1 Cotton fabric . 15
B.1.1 Sample details . 15
B.1.2 Test results . 15
B.2 Polyester fabric . 15
B.2.1 Sample detail . 15
B.2.2 Test results . 15
B.3 Polyamide fabric . 16
B.3.1 Sample detail . 16
B.3.2 Test results . 16
B.4 Wool fabric . 16
B.4.1 Sample detail . 17
B.4.2 Test results . 17
B.5 Calculation of repeatability and reproducibility . 17
Annex C (informative) Example of a practical testing apparatus. 20
Annex D (informative) Example of an interpretation of the test result . 22
Bibliography . 23
Foreword . ivi
Introduction . vii
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
iv © ISO 2023 – All rights reserved

---------------------- Page: 4 ----------------------
ISO/FDIS 18782:2023(E)
4 Principle . 2
5 Testing condition . 2
5.1 Low humidity air . 2
5.2 High humidity air . 2
6 Reagents and materials . 2
7 Apparatus . 2
8 Conditioning atmosphere for sampling . 8
9 Preparation of specimens . 8
10 Test procedure . 8
10.1 Mounting of test specimens . 8
10.2 Pretreatment process immediately before measurement . 9
10.3 Measurement process . 9
11 Calculation . 11
12 Test report . 11
Annex A (normative) Determination of the air flow rate for high humidity air . 12
Annex B (informative) Interlaboratory test results . 15
Annex C (informative) Example of a practical testing apparatus . 20
Annex D (informative) Example of an interpretation of the test result . 22
Bibliography . 23



© ISO 2023 – All rights reserved v

---------------------- Page: 5 ----------------------
ISO/FDIS 18782:2023(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/directiveswww.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/patentswww.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 of the voluntary nature of standards, 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
www.iso.org/iso/foreword.htmlwww.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 38, Textiles.
This second edition cancels and replaces the first edition (ISO 18782:2015), which has been technically
revised.
The main changes are as follows:
— in Clause 3, temperature definitions have been added;
— in Clause 7, Figure 1 has been changed from one testing position to 4 testing positions;
— in 7.2.5.5, rectifying plate was introduced for more stable testing;
— in Clause 9, the preconditioning by testing condition has been added.;
— in Annex A, the preconditioning by testing procedure has been added to the testing method for the
determination of air flow rate for high humidity.
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.htmlwww.iso.org/members.html.
vi © ISO 2023 – All rights reserved

---------------------- Page: 6 ----------------------
ISO/FDIS 18782:2023(E)
Introduction
In the apparel and clothing market, warm heat-comfort textile material is attracting consumers'
attention. It offers comfortable warmth through the combined technology of the hygroscopic heat
generation and heat insulation.
The phenomenon of the hygroscopic heat generation is known as a common function of natural fibres
especially, but not so much for synthetic fibres. Therefore, the synthetic fibre producers have been
developing fibres and textiles with an appropriate warm-feeling property.
This document provides a test method to obtain the practical heat generation of textiles under wearing
conditions.
The apparatus used in this test method has multiple test positions. So, this method is practical and
economical with high accuracy.
The International Organization for Standardization draws attention to the fact that it is claimed that
compliance with this document may involve the use of a patent.
ISO takes no position concerning the evidence, validity and scope of this patent right.
The holder of this patent right has assured ISO that he/she is willing to negotiate licenses under
reasonable and non-discriminatory terms and conditions with applicants throughout the world. In this
respect, the statement of the holder of this patent right is registered with ISO. Information may be
obtained from the patent database available at www.iso.org/patentswww.iso.org/patents.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights other than those in the patent database. ISO shall not be held responsible for identifying
any or all such patent rights.

© ISO 2023 – All rights reserved vii

---------------------- Page: 7 ----------------------
FINAL DRAFT INTERNATIONAL STANDARD ISO/FDIS 18782:2023(E)

Textiles — Determination of dynamic hygroscopic heat generation
1 Scope
This document specifies a test method for the determination of hygroscopic heat generated by flowing
low to high humidity air on one side of a surface. It is applicable to all kinds of sheet-shaped textile
materials.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements 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 105-F02, Textiles — Tests for colour fastness — Part F02: Specification for cotton and viscose
adjacent fabrics
ISO 139, Textiles — Standard atmospheres for conditioning and testing
ISO 3696, Water for analytical laboratory use — Specification and test methods
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https://www.iso.org/obphttps://www.iso.org/obp
— IEC Electropedia: available at https://www.electropedia.org/https://www.electropedia.org/
3.1
generated hygroscopic heat
hygroscopic heat generated by the loss of kinetic energy when gaseous water molecules are adsorbed
on a surface of textile material.
3.2
temperature at low humidity
Tinitial
initial equilibrium temperature at measurement side of a specimen when the low humidity air is
supplied.
3.3
generated hygroscopic heat temperature
ΔT
temperature difference between the initial equilibrium temperature and the temperature when the
high humidity air is supplied on measurement side of a specimen.
© ISO 2023 – All rights reserved 1

---------------------- Page: 8 ----------------------
ISO/FDIS 18782:2023(E)
3.4
maximum temperature at high humidity
T
max
maximum temperature at measurement side of a specimen when high humidity air is supplied.
3.5
maximum generated hygroscopic heat temperature
ΔT
max
maximum value of the generated hygroscopic heat temperature ΔT.
4 Principle
When the air supply is switched from low humidity to high humidity in instant, the temperature at the
specimen increases and reaches a peak due to the hygroscopic heat generation. The temperature at one
side of specimen is measured during this air change and the peak temperature is determined as ΔT .
max
In this test method, the high humidity air flow rate is determined by a cotton control specimen in which
the ΔT becomes 2,8 °C ± ± 0,3 °C.
max
5 Testing condition
5.1 Low humidity air
The air is taken from the atmosphere of the constant temperature and humidity chamber (7.1) in which
the temperature is controlled at 20 °C ± 2 °C and the humidity at (40 ± 3) % RH. The air flow rate is set
at 1,0 l/min ± 0,1 l/min.
5.2 High humidity air
The air in the constant temperature and humidity chamber (7.1) is passed through bubbling bottle
(7.2.2) and supplied to specimen as a high humidity air.
NOTE High humidity air is controlled by the air flow rate only; therefore, humidity measurements are not
essential. However, the humidity of high humidity air has been known as (90 ± 5) % RH.
6 Reagents and materials
6.1 Water, distilled water, ion exchanged water, grade 3 water according to ISO 3696 or equivalent for
humidifying air in a bubbling bottle (7.2.2).
6.2 Control specimen, a cotton adjacent fabric as specified in ISO 105-F02.
7 Apparatus
7.1 Constant temperature and humidity chamber or room, capable of maintaining the temperature
at 20 °C ± 2 °C and the humidity at (40 ± 3) % RH. The hygroscopic heat generation testing apparatus
(7.2) is placed in the chamber or room.
7.2 Hygroscopic heat generation testing apparatus, is shown in Figure 1. All devices are placed in
the chamber (7.1) in case of cabin type. If in case the oven type, the switching valve and control device
2 © ISO 2023 – All rights reserved

---------------------- Page: 9 ----------------------
ISO/FDIS 18782:2023(E)
(7.2.3) and monitoring recorder (7.3) are placed in the outside of the chamber. Air is supplied from one
air supply path to four measuring units. One photograph is shown in Annex C as
...

FINAL
INTERNATIONAL ISO/FDIS
DRAFT
STANDARD 18782
ISO/TC 38
Textiles — Determination of dynamic
Secretariat: SAC
hygroscopic heat generation
Voting begins on:
2023-02-20
Textiles — Détermination de la production de chaleur dynamique
hygroscopique
Voting terminates on:
2023-04-17
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 SUPPOR TING
DOCUMENTATION.
IN ADDITION TO THEIR EVALUATION AS
Reference number
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO-
ISO/FDIS 18782:2023(E)
LOGICAL, COMMERCIAL AND USER PURPOSES,
DRAFT INTERNATIONAL STANDARDS MAY ON
OCCASION HAVE TO BE CONSIDERED IN THE
LIGHT OF THEIR POTENTIAL TO BECOME STAN-
DARDS TO WHICH REFERENCE MAY BE MADE IN
NATIONAL REGULATIONS. © ISO 2023

---------------------- Page: 1 ----------------------
ISO/FDIS 18782:2023(E)
FINAL
INTERNATIONAL ISO/FDIS
DRAFT
STANDARD 18782
ISO/TC 38
Textiles — Determination of dynamic
Secretariat: SAC
hygroscopic heat generation
Voting begins on:
Textiles — Détermination de la production de chaleur dynamique
hygroscopique
Voting terminates on:
COPYRIGHT PROTECTED DOCUMENT
© ISO 2023
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.
RECIPIENTS OF THIS DRAFT ARE INVITED TO
ISO copyright office
SUBMIT, WITH THEIR COMMENTS, NOTIFICATION
OF ANY RELEVANT PATENT RIGHTS OF WHICH
CP 401 • Ch. de Blandonnet 8
THEY ARE AWARE AND TO PROVIDE SUPPOR TING
CH-1214 Vernier, Geneva
DOCUMENTATION.
Phone: [phone]
IN ADDITION TO THEIR EVALUATION AS
Reference number
Email: [e-mail]
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO­
ISO/FDIS 18782:2023(E)
Website: www.iso.org
LOGICAL, COMMERCIAL AND USER PURPOSES,
DRAFT INTERNATIONAL STANDARDS MAY ON
Published in Switzerland
OCCASION HAVE TO BE CONSIDERED IN THE
LIGHT OF THEIR POTENTIAL TO BECOME STAN­
DARDS TO WHICH REFERENCE MAY BE MADE IN
ii
  © ISO 2023 – All rights reserved
NATIONAL REGULATIONS. © ISO 2023

---------------------- Page: 2 ----------------------
ISO/FDIS 18782:2023(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 2
5 Testing condition . 2
5.1 Low humidity air . 2
5.2 High humidity air . 2
6 Reagents and materials . 2
7 Apparatus . 2
8 Conditioning atmosphere for sampling . 6
9 Preparation of specimens .6
10 Test procedure .6
10.1 Mounting of test specimens . 6
10.2 Pretreatment process immediately before measurement . 6
10.3 Measurement process . 6
11 Calculation . 7
12 Test report . 8
Annex A (normative) Determination of the air flow rate for high humidity air .9
Annex B (informative) Interlaboratory test results .11
Annex C (informative) Example of a practical testing apparatus .15
Annex D (informative) Example of an interpretation of the test result .16
Bibliography .17
iii
© ISO 2023 – All rights reserved

---------------------- Page: 3 ----------------------
ISO/FDIS 18782:2023(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 non­governmental, 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 of the voluntary nature of standards, 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
www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 38, Textiles.
This second edition cancels and replaces the first edition (ISO 18782:2015), which has been technically
revised.
The main changes are as follows:
— in Clause 3, temperature definitions have been added;
— in Clause 7, Figure 1 has been changed from one testing position to 4 testing positions;
— in 7.2.5.5, rectifying plate was introduced for more stable testing;
— in Clause 9, the preconditioning by testing condition has been added;
— in Annex A, the preconditioning by testing procedure has been added to the testing method for the
determination of air flow rate for high humidity.
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 2023 – All rights reserved

---------------------- Page: 4 ----------------------
ISO/FDIS 18782:2023(E)
Introduction
In the apparel and clothing market, warm heat-comfort textile material is attracting consumers'
attention. It offers comfortable warmth through the combined technology of the hygroscopic heat
generation and heat insulation.
The phenomenon of the hygroscopic heat generation is known as a common function of natural fibres
especially, but not so much for synthetic fibres. Therefore, the synthetic fibre producers have been
developing fibres and textiles with an appropriate warm-feeling property.
This document provides a test method to obtain the practical heat generation of textiles under wearing
conditions.
The apparatus used in this test method has multiple test positions. So, this method is practical and
economical with high accuracy.
The International Organization for Standardization draws attention to the fact that it is claimed that
compliance with this document may involve the use of a patent.
ISO takes no position concerning the evidence, validity and scope of this patent right.
The holder of this patent right has assured ISO that he/she is willing to negotiate licenses under
reasonable and non-discriminatory terms and conditions with applicants throughout the world. In
this respect, the statement of the holder of this patent right is registered with ISO. Information may be
obtained from the patent database available at www.iso.org/patents.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights other than those in the patent database. ISO shall not be held responsible for identifying
any or all such patent rights.
v
© ISO 2023 – All rights reserved

---------------------- Page: 5 ----------------------
FINAL DRAFT INTERNATIONAL STANDARD ISO/FDIS 18782:2023(E)
Textiles — Determination of dynamic hygroscopic heat
generation
1 Scope
This document specifies a test method for the determination of hygroscopic heat generated by flowing
low to high humidity air on one side of a surface. It is applicable to all kinds of sheet-shaped textile
materials.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements 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 105­F02, Textiles — Tests for colour fastness — Part F02: Specification for cotton and viscose adjacent
fabrics
ISO 139, Textiles — Standard atmospheres for conditioning and testing
ISO 3696, Water for analytical laboratory use — Specification and test methods
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
generated hygroscopic heat
hygroscopic heat generated by the loss of kinetic energy when gaseous water molecules are adsorbed
on a surface of textile material
3.2
temperature at low humidity
T
initial
initial equilibrium temperature at measurement side of a specimen when the low humidity air is
supplied
3.3
generated hygroscopic heat temperature
ΔT
temperature difference between the initial equilibrium temperature and the temperature when the
high humidity air is supplied on measurement side of a specimen
3.4
maximum temperature at high humidity
T
max
maximum temperature at measurement side of a specimen when high humidity air is supplied
1
© ISO 2023 – All rights reserved

---------------------- Page: 6 ----------------------
ISO/FDIS 18782:2023(E)
3.5
maximum generated hygroscopic heat temperature
ΔT
max
maximum value of the generated hygroscopic heat temperature ΔT
4 Principle
When the air supply is switched from low humidity to high humidity in instant, the temperature at the
specimen increases and reaches a peak due to the hygroscopic heat generation. The temperature at one
side of specimen is measured during this air change and the peak temperature is determined as ΔT .
max
In this test method, the high humidity air flow rate is determined by a cotton control specimen in which
the ΔT becomes 2,8 °C ± 0,3 °C.
max
5 Testing condition
5.1 Low humidity air
The air is taken from the atmosphere of the constant temperature and humidity chamber (7.1) in which
the temperature is controlled at 20 °C ± 2 °C and the humidity at (40 ± 3) % RH. The air flow rate is set
at 1,0 l/min ± 0,1 l/min.
5.2 High humidity air
The air in the constant temperature and humidity chamber (7.1) is passed through bubbling bottle
(7.2.2) and supplied to specimen as a high humidity air.
NOTE High humidity air is controlled by the air flow rate only; therefore, humidity measurements are not
essential. However, the humidity of high humidity air has been known as (90 ± 5) % RH.
6 Reagents and materials
6.1 Water, distilled water, ion exchanged water, grade 3 water according to ISO 3696 or equivalent
for humidifying air in a bubbling bottle (7.2.2).
6.2 Control specimen, a cotton adjacent fabric as specified in ISO 105-F02.
7 Apparatus
7.1 Constant temperature and humidity chamber or room, capable of maintaining the
temperature at 20 °C ± 2 °C and the humidity at (40 ± 3) % RH. The hygroscopic heat generation testing
apparatus (7.2) is placed in the chamber or room.
7.2 Hygroscopic heat generation testing apparatus, shown in Figure 1. All devices are placed in
the chamber (7.1) in case of cabin type. If in case the oven type, the switching valve and control device
(7.2.3) and monitoring recorder (7.3) are placed in the outside of the chamber. Air is supplied from one
2
  © ISO 2023 – All rights reserved

---------------------- Page: 7 ----------------------
ISO/FDIS 18782:2023(E)
air supply path to four measuring units. One photograph is shown in Annex C as an example of practical
testing apparatus.
Key
Key
1 specimen 10 air bubbling bottle with water
2 specimen holder 11, 12 switching valve
3 specimen table 13, 14 flow control valve
4 air lid 15 humidity sensor
5 rectifying plate 16 air supply path
6 thermometer 17 control device
7 flowmeter with regulating valve 18 monitoring recorder
8 measuring units 19 constant temperature and humidity chamber
9 air pump
Figure 1 — Schematic diagram of the testing apparatus
7.2.1 Air pump, capable of collecting air from the atmosphere of the chamber (7.1) and supplying air
to the specimen at a rate of 1,0 l/min ± 0,1 l/min.
7.2.2 Bubbling bottle, consisting of an air­tight bottle with an air inlet tube attached to a porous
cylinder such as air stones to make fine air bubbles and with air outlet tube to collect high humidity air
after bubbling. Completely submerge the porous cylinder in water during testing.
7.2.3 Switching valve with control device, used for switching to low humidity air path (11, 13, 12
...