oSIST prEN ISO 23537-1:2021

Requirements for sleeping bags - Part 1: Thermal, mass and dimensional requirements for sleeping bags designed for limit temperatures of ‐20°C and higher (ISO/DIS 23537-1:2021)

Anforderungen an Schlafsäcke - Teil 1: Thermische Anforderungen, Masse und Abmessungen an Schlafsäcke, die für Grenztemperaturen von -20 °C und höher ausgelegt sind (ISO/DIS 23537 1:2021)

Exigences pour les sacs de couchage - Partie 1: Exigences thermiques, massiques et dimensionnelles pour les sacs de couchage conçus pour des températures limites de -20°C et plus (ISO/DIS 23537-1:2021)

Zahteve za spalne vreče - 1. del: Toplotne, masne in dimenzionalne zahteve za spalne vreče, izdelane za mejne temperature –20 °C in več (ISO/DIS 23537-1:2021)

General Information

• Status: Not Published
• Public Enquiry End Date: 25-Sep-2021
• ICS: 97.200.30 - Camping equipment and camp-sites
• Technical Committee: SPO - Sports
• Current Stage: 4020 - Public enquire (PE) (Adopted Project)
• Start Date: 19-Jul-2021
• Due Date: 06-Dec-2021
• Ref Project: prEN ISO 23537-1 - Requirements for sleeping bags - Part 1: Thermal, mass and dimensional requirements for sleeping bags designed for limit temperatures of ‐20°C and higher (ISO/DIS 23537-1:2021)

RELATIONS

• Revised: SIST EN ISO 23537-1:2017/A1:2018 - Requirements for sleeping bags - Part 1: Thermal and dimensional requirements - Amendment 1 (ISO 23537-1:2016/Amd1:2018)
• Effective Date: 31-Mar-2021
• Revised: SIST EN ISO 23537-1:2017 - Requirements for sleeping bags - Part 1: Thermal and dimensional requirements (ISO 23537-1:2016)
• Effective Date: 31-Mar-2021

Standards Content (sample)

SLOVENSKI STANDARD
oSIST prEN ISO 23537-1:2021
01-september-2021
Zahteve za spalne vreče - 1. del: Toplotne, masne in dimenzionalne zahteve za
spalne vreče, izdelane za mejne temperature –20 °C in več (ISO/DIS 23537-1:2021)

Requirements for sleeping bags - Part 1: Thermal, mass and dimensional requirements

for sleeping bags designed for limit temperatures of ‐20°C and higher (ISO/DIS 23537-

1:2021)
Anforderungen an Schlafsäcke - Teil 1: Thermische Anforderungen, Masse und
Abmessungen an Schlafsäcke, die für Grenztemperaturen von -20 °C und höher
ausgelegt sind (ISO/DIS 23537 1:2021)

Exigences pour les sacs de couchage - Partie 1: Exigences thermiques, massiques et

dimensionnelles pour les sacs de couchage conçus pour des températures limites de -

20°C et plus (ISO/DIS 23537-1:2021)
Ta slovenski standard je istoveten z: prEN ISO 23537-1
ICS:
97.200.30 Oprema za taborjenje in Camping equipment and
tabori camp-sites
oSIST prEN ISO 23537-1:2021 en,fr,de

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

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oSIST prEN ISO 23537-1:2021
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oSIST prEN ISO 23537-1:2021
DRAFT INTERNATIONAL STANDARD
ISO/DIS 23537‐1
ISO/TC 83 Secretariat: DIN
Voting begins on: Voting terminates on:
2021‐07‐05 2021‐09‐27
Requirements for sleeping bags —
Part 1:
Thermal, mass and dimensional requirements for sleeping
bags designed for limit temperatures of ‐20°C and higher
ICS: 97.200.30
THIS DOCUMENT IS A DRAFT CIRCULATED
This document is circulated as received from the committee secretariat.
FOR COMMENT AND APPROVAL. IT IS
THEREFORE SUBJECT TO CHANGE AND MAY
NOT BE REFERRED TO AS AN INTERNATIONAL
STANDARD UNTIL PUBLISHED AS SUCH.
IN ADDITION TO THEIR EVALUATION AS
ISO/CEN PARALLEL PROCESSING
BEING ACCEPTABLE FOR INDUSTRIAL,
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
STANDARDS MAY ON OCCASION HAVE TO
BE CONSIDERED IN THE LIGHT OF THEIR
POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
Reference number
NATIONAL REGULATIONS.
ISO/DIS 23537-1:2021(E)
RECIPIENTS OF THIS DRAFT ARE INVITED
TO SUBMIT, WITH THEIR COMMENTS,
NOTIFICATION OF ANY RELEVANT PATENT
RIGHTS OF WHICH THEY ARE AWARE AND TO
PROVIDE SUPPORTING DOCUMENTATION. ISO 2021
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oSIST prEN ISO 23537-1:2021
ISO/DIS 23537‐1:2021(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2021

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

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

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

below or ISO’s member body in the country of the requester.
ISO copyright office
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Phone: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii © ISO 2021 – All rights reserved
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oSIST prEN ISO 23537-1:2021
ISO/DIS 23537‐1:2021(E)
Contents Page

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

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

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

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

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

4 Requirements .......................................................................................................................................................................................................... 3

4.1 Thermal properties for lower temperature limits ................................................................................................... 3

4.2 Water vapour permeability index ........................................................................................................................................... 3

4.3 Inside dimensions ................................................................................................................................................................................ 4

4.3.1 Inside length ........................................................................................................................................................................ 4

4.3.2 Maximum inside width ............................................................................................................................................... 4

4.3.3 Inside foot width .............................................................................................................................................................. 4

4.4 Total mass .................................................................................................................................................................................................... 4

5 Test methods ............................................................................................................................................................................................................. 4

5.1 Testing of the thermal properties ........................................................................................................................................... 4

5.1.1 Principle .................................................................................................................................................................................. 4

5.1.2 Thermal manikin ............................................................................................................................................................. 4

5.1.3 Climatic room ..................................................................................................................................................................... 5

5.1.4 Artificial ground ............................................................................................................................................................... 5

5.1.5 Test samples and pre-treatment ........................................................................................................................ 5

5.1.6 Thermal resistance for posture 1 R (1) ....................................................................................................... 5

5.1.7 Test procedure ................................................................................................................................................................... 6

5.1.8 Calculation of temperatures of the range of utility ............................................................................ 6

5.2 Testing of the water vapour permeability index ........................................................................................................ 6

5.3 Measurement of inside dimension ........................................................................................................................................ 7

5.3.1 Inside length ........................................................................................................................................................................ 7

5.3.2 Maximum inside length.............................................................................................................................................. 7

5.3.3 Inside foot width .............................................................................................................................................................. 7

5.4 Testing of the total mass ................................................................................................................................................................. 7

6 Test report ................................................................................................................................................................................................................... 7

7 Labelling ........................................................................................................................................................................................................................ 8

7.1 Graph for the range of utility ...................................................................................................................................................... 8

7.2 Marking ......................................................................................................................................................................................................... 8

7.3 Information supplied to the consumer .............................................................................................................................. 9

Annex A (normative) Reference values of thermal resistance for calibration of thermal manikin 11

Annex B (informative) Precision of test results .....................................................................................................................................13

Annex C (normative) Physiological model for calculation of range of utility .........................................................14

Annex D (informative) Warning of misuse of temperature rating ......................................................................................19

Annex F (informative) Maximum temperature .......................................................................................................................................22

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oSIST prEN ISO 23537-1:2021
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Foreword

ISO (the International Organization for Standardization) is a worldwide federation of national standards

bodies (ISO member bodies). The work of preparing International Standards is normally carried out

through ISO technical committees. Each member body interested in a subject for which a technical

committee has been established has the right to be represented on that committee. International

organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.

ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of

electrotechnical standardization.

The procedures used to develop this document and those intended for its further maintenance are

described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the

different types of ISO documents should be noted. This document was drafted in accordance with the

editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).

Attention is drawn to the possibility that some of the elements of this document may be the subject of

patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of

any patent rights identified during the development of the document will be in the Introduction and/or

on the ISO list of patent declarations received (see www .iso .org/ patents).

Any trade name used in this document is information given for the convenience of users and does not

constitute an endorsement.

For an explanation 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 83, Sports and other recreational

facilities and equipment, in collaboration with the European Committee for Standardization (CEN)

Technical Committee CEN/TC 136, Sports, playgrounds and other recreational facilities and equipment

in accordance with the Agreement on technical cooperation between ISO and CEN (Vienna Agreement).

This second edition cancels and replaces the first edition (ISO 23537-1:2016), which has been technically

revised.
The main changes compared to the previous edition are as follows:
— Modification of definitions;
— Made clearer that extreme climate conditions are included;
— Revision of requirements for lower temperature limits;
— Revision of the requirements and test methods;

— Revision of Clause 7, labelling, and inclusion of a revised Figure 1 to be clearer;

— Revision of the reference values of thermal resistance for calibration of thermal manikin;

— Deletion of Annex F “Maximum temperature”.

ISO 23537 consists of the following parts, under the general title, Requirements for sleeping bags:

— Part 1: Thermal, mass and dimensional requirements for sleeping bags designed for limit temperatures

of ‐20°C and higher
— Part 2: Fabric and material properties
A list of all parts in the ISO 23537 series can be found on the ISO website.
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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.
© ISO 2021 – All rights reserved v
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Introduction

This second edition of this part of ISO 23537 is based on continued development of the European

Standard, EN 13537, and the first edition of the International Standard, ISO 23537-1.

This International Standard consists of two parts which allows for separate validation of thermal

properties and product and material performance. This separation of parts also allows for continued

development of new product combinations as it encourages manufacturers to consider new

combinations of materials which for example might not be suitable to test by traditional textile physical

tests, but which can still have thermal properties evaluated.

This part of ISO 23537 considers important aspects to the thermal performance of the sleeping bag.

During the development of this part of ISO 23537, consideration was given to the need to continue to

reduce inter laboratory variability of the thermal testing and a number of test parameters have been

tightened as a consequence.
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oSIST prEN ISO 23537-1:2021
DRAFT INTERNATIONAL STANDARD ISO/DIS 23537‐1:2021(E)
Requirements for sleeping bags —
Part 1:
Thermal, mass and dimensional requirements for sleeping
bags designed for limit temperatures of ‐20°C and higher
1 Scope

This part of ISO 23537 specifies the requirements and test methods as well as provisions for labelling of

adult sized sleeping bags for use in sports and leisure time activities at a limit temperature of ≥ -20 °C in

regard to thermal characteristics, dimensions and mass.

This part of ISO 23537 does not apply to sleeping bags intended for specific purpose such as military

use and extreme climate zone expedition. It does not apply to sleeping bags for children or babies.

NOTE 1 No prediction model exists for the determination of the limiting temperatures based on the thermal

resistance of the sleeping bag for children and babies. Moreover, such a model for testing cannot be developed

because the necessary controlled sleep trials with children or babies in climatic chambers are, out of ethical

reasons, not permitted.

This part of ISO 23537 describes the method for the assessment of the performance in steady-state

conditions of a sleeping bag with regard to the protection against cold.

NOTE 2 Sleeping bags without homogeneous fillings designed to provide local extra insulation in certain

parts pose issues with the calibration and/or test procedure. Ongoing work continues to provide suitable means

of establishing temperature ratings.
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 139, Textiles — Standard atmospheres for conditioning and testing ISO 1096, Plywood — Classification

ISO 3758, Textiles — Care labelling code using symbols

ISO 11092, Textiles — Physiological effects — Measurement of thermal and water‐vapour resistance under

steady‐state conditions (sweating guarded‐hotplate test)
ISO 1096, Plywood — Classification

ISO 15831:2004, Clothing — Physiological effects — Measurement of thermal insulation by means of a

thermal manikin

EN 13088, Manufactured articles filled with feather and down — Method for the determination of a filled

product’s total mass and of the mass of the filling
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
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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
comfort temperature
comf

lower limit of the comfort range, down to which a sleeping bag user with a relaxed posture, such as

lying on their back, is globally in thermal equilibrium and just not feeling cold

Note 1 to entry: For more information, see C.7.3
3.2
limit temperature
lim

lower limit at which a sleeping bag user with a curled up body posture is globally in thermal equilibrium

and just not feeling cold
Note 1 to entry: For more information, see C.7.2.
3.3
extreme temperature
ext
very low temperature where the risk of health damage by hypothermia is possible
Note 1 to entry: For more information, see C.7.1.
Note 2 to entry: This is a point of danger which can lead to death
3.4
maximum temperature
max

upper limit of comfort range, up to which a partially uncovered sleeping bag user just does not perspire

too much
Note 1 to entry: For more information, see Annex F.
3.5
thermal manikin

dummy with human shape and heated body surface which allows the determination of thermal transfer

through the sleeping bag under steady-state conditions

Note 1 to entry: i.e. constant heat flux and temperature gradient between body surface and ambient air.

3.6
thermal resistance
R , thermal insulation

property of the sleeping bag which is related to the dry heat loss of the sleeping bag user, effected by the

difference of temperature between the skin and the ambient air, as measured with a thermal manikin

Note 1 to entry: The dry heat loss of the sleeping bag user is a combination of conductive, convective and radiative

heat transfer

Note 2 to entry: This thermal resistance represents the insulative property of a sleeping bag, which includes

the effects of the shell fabrics and filling materials, air volume in the cavity inside the sleeping bag, boundary

air layer on the outer face of the sleeping bag, mattress underneath the sleeping bag and garments worn by the

sleeping bag user. It is considered to be the total thermal insulation (see ISO 15831).

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4 Requirements
4.1 Thermal properties for lower temperature limits

Depending on the thermal resistance posture 1 R (1), the values for the extreme temperature (T ),

c ext

limit temperature (T ) and comfort temperature (T ) as given in Table 1 shall be used. If the thermal

lim comf

resistances posture 1 R (1) measured for the sleeping bag is in between the values in Table 1, a linear

interpolation shall be performed on the basis of the nearest upper and lower values of the thermal

resistances posture 1 R (1)
Test in accordance with 5.1.6.
Table 1 — Lower temperature limits of the range of utility
Thermal resistance Extreme temperature Limit temperature Comfort temperature
posture 1
T T T
R (1) ext lim comf
m ∙K/W °C °C °C
0,500 +5,0 +14,2 +17,2
0,540 +2,8 +12,7 +15,9
0,580 +0,6 +11,2 +14,6
0,620 –1,5 +9,7 +13,3
0,660 –3,7 +8,1 +12,0
0,700 –5,8 +6,6 +10,7
0,740 –7,9 +5,1 +9,4
0,780 –10,1 +3,6 +8,1
0,820 –12,2 +2,2 +6,9
0,860 –14,3 +0,7 +5,6
0,900 –16,3 –0,8 +4,3
0,940 –18,4 –2,3 +3,1
0,980 –20,5 –3,7 +1,8
1,020 –22,5 –5,2 +0,6
1,060 –24,5 –6,7 –0,7
1,100 –26,5 –8,1 –1,9
1,140 –28,5 –9,5 –3,1
1,180 –30,5 –11,0 –4,4
1,220 –32,5 –12,4 –5,6
1,260 –34,4 –13,8 –6,8
1,300 –36,4 –15,2 –8,0
1,340 –38,3 –16,7 –9,2
1,380 –40,2 –18,1 –10,4
1,420 –42,2 –19,5 –11,6
4.2 Water vapour permeability index

The material specific water-vapour permeability index (i ) of the sleeping bag shall be ≥ 0,45.

NOTE The water-vapour permeability index is dimensionless, and has values between 0 and 1. A value of

0 implies that the material is water-vapour impermeable, that is, it has infinite water-vapour resistance, and a

material with a value of 1 has both the thermal resistance and water-vapour resistance of an air layer of the same

thickness.
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Test in accordance with 5.2.
4.3 Inside dimensions
4.3.1 Inside length

The inside length of the sleeping bag shall be given with a tolerance of ± 3 cm. Test in accordance with

5.3.1
4.3.2 Maximum inside width

The maximum inside width of the sleeping bag shall be given with a tolerance of ± 2 cm. Test in

accordance with 5.3.2.
4.3.3 Inside foot width

The inside foot width of the sleeping bag shall be given with a tolerance of ± 2 cm. Test in accordance

with 5.3.3
4.4 Total mass

The total mass of the sleeping bag shall be given with a tolerance of ± 5 % for synthetic and down

sleeping bag. Test in accordance with 5.4
5 Test methods
5.1 Testing of the thermal properties
5.1.1 Principle

The thermal resistance of the sleeping bag is measured with a thermal manikin which meets the

requirements and test procedure of ISO 15831 and which is inserted into the sleeping bag and placed in

a controlled atmosphere.

A physiological model is then applied which uses this thermal resistance to determine ambient

temperatures corresponding to a range of utility of the sleeping bag.

The manikin test of this part of ISO 23537 is suitable for mummy shaped bags which appropriately fit to

the manikin so to be accurate. The temperature rating result can be applied to other sized mummy bags

that uses the same materials and insulation construction which is proportionally scaled up or down

from the tested bag.
5.1.2 Thermal manikin
5.1.2.1 General

A thermal manikin according to ISO 15831 with the body height of (1,70 ± 0,15) m shall be used. During

the test, the manikin shall be dressed with the following garments:

— two-piece suit (upper part with long sleeves, trousers) with a material specific thermal resistance

tested (R ) in accordance with ISO 11092 of
2 2
R = (0,040 m ∙K/W to 0,060 m K/W (1)

— knee-length socks with a material specific thermal resistance tested in accordance with ISO 11092

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2 2
R = (0,040 m ∙K/W to 0,060 m ∙K/W) (2)

The thermal manikin's skin temperature shall be in accordance with ISO 15831:2004, Clause 7.

5.1.2.2 Calibration of thermal manikin

In order to calibrate a specific thermal manikin and the related operating conditions, the measurement

shall be performed on the reference set of sleeping bags in accordance with Table A.1.

A linear or exponential correlation shall be found between the thermal resistance figures issued from

the measurement and the reference values for the thermal resistances posture 1 R (1) of the reference

set of sleeping bags (see Table A.1).
NOTE See Annex A.

The deviation of the corrected values of the thermal resistances posture 1 R (1) obtained by applying

this linear or exponential correlation from the reference thermal resistance values of the reference set

of sleeping bags shall fulfil the following requirements:

a) mean deviation with the complete set of the reference sleeping bags is < 5 % (variation coefficient);

b) no individual deviation is > 10 % (variation coefficient);

c) the repeatability of the measurement on each sleeping bag shall be better than 4 % (variation

coefficient).
5.1.3 Climatic room

The test shall be performed in a climatic room with an air speed, a heat flux and a relative humidity in

accordance with ISO 15831:2004, Clause 7.

The ambient temperature shall be (10 ± 5) °C. During the test, the fluctuation of the ambient temperature

shall be in accordance with ISO 15831:2004, 5.2.1.

NOTE Highly insulative sleeping bags might not allow the heat flux to be ≥ 20 W/m2. In these cases, an

ambient temperature of the lowest value within this range is seen as appropriate.

5.1.4 Artificial ground

The test shall be operated with the thermal manikin placed into the sleeping bag in accordance with

5.1.6.1, lying on a foam mattress with a material specific thermal resistance R = (0,85 ± 0,06) m K/W

when tested in accordance with ISO 11092 and placed on an artificial ground. This ground shall consist

of a wooden board according to ISO 1096, large enough that no part of the manikin or the sleeping bag

protrudes over the board, with a thickness of (20 ± 2) mm.

The artificial ground is held at least 100 mm above the floor by some kind of support which allows air

circulation underneath the artificial ground.
5.1.5 Test samples and pre‐treatment

Before testing, the sleeping bag shall be dry tumbled in a dryer with a capacity of ≥ 250 l without any

additional load for 15 min at a temperature of < 30 °C. After this dry tumbling and immediately prior to

the test, it shall be conditioned for ≥ 12 h in the ambient conditions of the test.

5.1.6 Thermal resistance for posture 1 R (1)

The thermal resistance posture 1 R (1) is measured with the thermal manikin completely inserted into

the sleeping bag and lying on its back. The bag's zippers, if any, are closed. The bag's hood, if present,

1) The reference sets of sleeping bags are available from:
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covers the manikin's head, and the cords of the hood are tightened as much as possible without using

any additional aids (e.g. clothes pins, etc.) not supplied with the sleeping bag.

For sleeping bags that have hood draw cords with which the hood aperture can be closed to < 120 mm

diameter or < 375 mm perimeter, a cold-protective mask shall be used on the manikin's face. For

sleeping bags with hood draw cords with which the hood aperture cannot be closed to < 120 mm

diameter or < 375 mm perimeter, a cold-protective mask shall not be used on the manikin's face. For

sleeping bags that do not have a hood or do not have hood draw cords, a cold-protective mask shall not

be used.

NOTE 1 Test rectangular bags may encounter excessive heat loss in bare head area when tested which would

result in overly conservative results.

The thermal resistance posture 1 R (1) is determined using either the serial or the parallel calculation

method according to ISO 15831. The same calculation method shall be used for the sleeping bags being

tested as was used for the reference set of sleeping bags.
5.1.7 Test procedure
The test shall be performed according to the requirements in 4.1.

For each specific thermal manikin, the position of the arms and legs in relation to the torso of the

manikin, the wooden board and the artificial ground shall be defined as part of the calibration

procedure and remain the same in all the tests performed according to this part of ISO 23537.

Calculate the value of the thermal resistance posture 1 R (1) by applying the same calculation method

and correlation gained from the calibration procedure as given in 5.1.2.2.

Three separate tests shall be completed; each commencing from the insertion of the manikin into the

sleeping bag. The arithmetic mean value of the thermal resistance of the sleeping bag shall then be

calculated.

If the tests cannot be completed using three separate sleeping bags, then use of a single bag is

permissible however it shall undergo the pre-treatment in accordance with 5.1.5 in between individual

tests, and the test report shall show a single bag was used.
5.1.8 Calculation of temperatures of the range of utility
The sleeping bag's extreme temperature (T ), limit temperatur
...