ISO/FDIS 6324

FINAL DRAFT INTERNATIONAL STANDARD
ISO/FDIS 6324:2023(E)
ISO/TC 163/SC 3
Date: 2023-06
Secretariat: SCC
Date: 2023-08-24
Thermal insulation products — Flexible microporous thermal
insulation for industrial applications — Specification
FDIS stage

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ISO/FDIS 6324:2023(E)
© ISO 2023
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ISO/FDIS 6324:2023(E)


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ISO/FDIS 6324:2023(E)
Foreword
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electrotechnical standardization.
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described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
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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
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Field Code Changed
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FINAL DRAFT INTERNATIONAL STANDARD ISO/FDIS 6324:2023(E)

Thermal insulation products — Flexible microporous thermal
insulation for industrial applications — Specification
1 Scope
This document specifies the requirements for factory-made flexible microporous insulation (FMI), which
areis used for the thermal insulation of industrial applications. This documentIt 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.
This documentIt 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
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ISO/FDIS 6324:2023(E)
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
2
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 fabric,
silica fibre fabric) and stitched with sewing thread for flexibility
3.2 Symbols and units
Symbol Quantity Unit
l length mm
b width mm
t thickness mm
Δε , relative change in length %
l
Δεb relative change in width %
Δεt relative change in thickness %
λ thermal conductivity W/(m·K)
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ISO/FDIS 6324:2023(E)
Symbol Quantity Unit
λ declared thermal conductivity as determined by W/(m·K)
D
ISO 13787, and expressed with three significant digits
3.3 Abbreviated terms
3.3.1 Abbreviated terms
Abbreviated term Meaning
FMI Flexible microporous insulation
ITT Initial type test
FPC Factory production control
3.3.2 Abbreviated terms for declared properties
Abbreviated term Declared property
ST (+) declared level for maximum service temperature
CS(Y) declared level for compressive strength
CS(10) declared level for compressive strength at 10 % deformation
Cl declared level for chloride content
T declared level for thickness
4 Requirements
4.1 General
Product properties shall be assessed in accordance with Clause 5.Clause 5. To conform to this document,
products shall meet the requirements of 4.2,4.2, and the requirements of 4.3,4.3, as appropriate.
The test methods for the determination of each property are given in Table 6,Table 6, which also shows
the required test specimen dimensions and the minimum number of test specimens required to give one
test result.
One test result for a product property is the average of the measured values on the number of test
specimens given in Table 6.Table 6.
4.2 For all applications
4.2.1 Linear dimensions
Length and width shall be measured in accordance with ISO 29465 for each of the four specimens.
A minimum of four measurements shall be made for each dimension. Each value shall be within the
tolerances specified in Table 1.Table 1.
The thickness of microporous insulation shall be measured in accordance with ISO 29466 by using a
square plate under pressure of 250 Pa and shall be subject to the tolerances detailed in Table 1.Table 1.
The pressure employed during measurement shall be disclosed.
Tighter tolerances can be necessary for certain applications; this shall be agreed by the supplier and
purchaser.
Table 1 — Dimensional tolerances
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ISO/FDIS 6324:2023(E)
Length Width Thickness
Nominal Tolerance(mm) Nominal Tolerance(mm) Nominal Tolerance (%)
≤ 1 m -−0 / +10 ≤ 1 m -−0 / +10 T1 -−0 / +2
T2 -−0 / +5
1 m ~ -−0 / +15 1 m ~ -−0 / +15 T3 -−0 / +10
3 m 3 m
T4 -−0 / +15
> 3 m -−0 / +20 > 3 m -−0 / +20 T5 -−0 / > +15

4.2.44.2.2 Density
Density shall be determined in accordance with ISO 29470 in each of the four specimens and reported as
the average of the four specimens.
4.2.54.2.3 Thermal conductivity
For thermal conductivity testing, the specimen shall be conditioned according to 5.2.5.2.
Thermal conductivity shall be based upon measurements carried out in accordance with ISO 8301 or
ISO 8302.
The measured values shall be expressed with three significant figures and the test mean temperatures
shall be according to Table 2Table 2 depending on the usage environment and requirement.
The declared thermal conductivity shall be determined in accordance with ISO 23993.
Table 2 — Thermal conductivity category
Test mean temperature
10 °C or 23 °C
100 °C
Thermal
200 °C
conductivity (λ)
300 °C
400 °C
500 °C
4.3 For specific applications
4.3.1 Reaction to fire
The fire properties with respect to reaction to fire should be assessed.
NOTE Legislation can apply regarding reaction to fire in the individual territories where the product is used,
can apply.
4.3.2 Water absorption
The test shal
...