ISO 6324:2024

International
Standard
ISO 6324
First edition
Thermal insulation products —
2024-01
Flexible microporous insulation
for industrial applications —
Specification
Reference number
© ISO 2024
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Published in Switzerland
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Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms, definitions, symbols and abbreviated terms . 2
3.1 Terms and definitions .2
3.2 Symbols and units .2
3.3 Abbreviated terms .3
3.3.1 Abbreviated terms .3
3.3.2 Abbreviated terms for declared properties .3
4 Requirements . 3
4.1 General .3
4.2 For all applications .3
4.2.1 Linear dimensions . . .3
4.2.2 Density .4
4.2.3 Thermal conductivity .4
4.3 For specific applications .4
4.3.1 Reaction to fire.4
4.3.2 Water absorption .4
4.3.3 Water vapour transmission .5
4.3.4 Permanent linear change .5
4.3.5 Compressive strength .5
4.3.6 Corrosiveness to steel .5
4.3.7 Resistance to fungi .5
4.3.8 Flexibility .6
5 Test methods . 6
5.1 Sampling .6
5.2 Conditioning.6
5.3 Testing .6
5.3.1 General .6
5.3.2 Thermal conductivity .7
5.3.3 Permanent linear change .7
6 Designation code . . 7
7 Evaluation of conformity . . 8
8 Marking and labelling . 8
Annex A (normative) Factory production control (FPC) . 9

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Foreword
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This document was prepared by Technical Committee ISO/TC 163, Thermal performance and energy use in
the built environment, Subcommittee SC 3, Thermal insulation products, components and systems.
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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International Standard ISO 6324:2024(en)
Thermal insulation products — Flexible microporous
insulation for industrial applications — Specification
1 Scope
This document specifies the requirements for factory-made flexible microporous insulation (FMI), which
is used for the thermal insulation of industrial applications. It specifies requirements for insulation that
exhibits thermal insulating performance through nano-sized pore composite material comprising a blend of
inorganic powder, fibres and opacifiers. The products are delivered as a flexible microporous type.
This document describes product characteristics and includes procedures for testing, evaluation of
conformity, marking and labelling.
It does not specify the required level of a given property to be achieved by a product to demonstrate fitness
for purpose in a particular application. The levels required for a given application can be found in regulations
or non-conflicting standards.
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 846:2019, Plastics — Evaluation of the action of microorganisms
ISO 1663, Rigid cellular plastics — Determination of water vapour transmission properties
ISO 8301, Thermal insulation — Determination of steady-state thermal resistance and related properties —
Heat flow meter apparatus
ISO 8302, Thermal insulation — Determination of steady-state thermal resistance and related properties —
Guarded hot plate apparatus
ISO 23993, Thermal insulation products for building equipment and industrial installations — Determination of
design thermal conductivity
ISO 12576-1, Thermal insulation — Insulating materials and products for buildings — Conformity control
systems — Part 1: Factory-made products
ISO 12624, Thermal insulating products for building equipment and industrial installations — Determination of
trace quantities of water-soluble chloride, fluoride, silicate, sodium ions and pH
ISO 13787, Thermal insulation products for building equipment and industrial installations — Determination of
declared thermal conductivity
ISO 16535, Thermal insulating products for building applications — Determination of long-term water
absorption by immersion
ISO 18097, Thermal insulating products for building equipment and industrial installations — Determination of
maximum service temperature
ISO 29465, Thermal insulating products for building applications — Determination of length and width
ISO 29466, Thermal insulating products for building applications — Determination of thickness

ISO 29469:2022, Thermal insulating products for building applications — Determination of compression
behaviour
ISO 29470, Thermal insulating products for building applications — Determination of the apparent density
ISO 29767, Thermal insulating products for building applications — Determination of short-term water
absorption by partial immersion
3 Terms, definitions, symbols and abbreviated terms
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
3.1 Terms and definitions
3.1.1
inorganic powder
base ingredient of microporous thermal insulation (e.g. fumed silica) composed of SiO and fumed alumina
oxide
3.1.2
microporous
composite material that comes in the form of fibre reinforced inorganic powder (e.g. small particles of
dispersed silica), creating micro-pores
3.1.3
flexible microporous thermal insulation
type of microporous thermal insulation that is encased in incombustible fabric (e.g. glass fibre fa
...