Overview
ISO 6324:2024 - "Thermal insulation products - Flexible microporous insulation for industrial applications - Specification" (First edition, 2024) defines requirements for factory-made flexible microporous insulation (FMI) used in industrial thermal insulation. The standard covers product description, key characteristics, sampling and test procedures, evaluation of conformity, and marking and labelling. It applies to FMI made from a nano‑sized pore composite (inorganic powder, fibres and opacifiers) delivered as a flexible microporous type, and explicitly does not prescribe application-specific performance levels (these come from regulations or other standards).
Key Topics and Requirements
- Material and construction: FMI described as a fibre‑reinforced inorganic powder composite encased in incombustible fabric (e.g., glass or silica fibre) and stitched for flexibility.
- Dimensional control: Measurement of length, width and thickness (thickness measured under 250 Pa) with specified tolerances and minimum specimen counts.
- Density and thermal performance: Density measured per ISO 29470; thermal conductivity testing in accordance with ISO 8301 or ISO 8302; declared thermal conductivity determined per ISO 23993 and expressed to three significant digits.
- Service temperature and dimensional stability: Permanent linear change tested per ISO 18097 with declared maximum service temperature (ST) levels (steps of 100 °C).
- Durability and resistance: Requirements and tests for water absorption (ISO 29767 or ISO 16535), water vapour transmission (ISO 1663), compressive strength, corrosiveness to steel, resistance to fungi (ISO 846), and flexibility.
- Reaction to fire: Assessment of reaction to fire as applicable; users must consider applicable local legislation.
- Quality control and conformity: Sampling, conditioning, testing procedures, a designation code, and requirements for factory production control (FPC - Annex A) and evaluation of conformity.
Applications and Who Uses This Standard
ISO 6324:2024 is intended for:
- Manufacturers of factory‑made FMI to specify production, testing and labelling requirements.
- Thermal insulation specifiers and engineers selecting materials for industrial piping, vessels, furnaces and high‑temperature equipment where low thermal conductivity and flexibility are needed.
- Procurement and quality assurance teams requiring standardised test methods and conformity evidence.
- Testing laboratories and conformity assessors performing measurements and FPC verification.
Note: designers and end users must identify required property levels from applicable regulations or non-conflicting standards for specific applications.
Related Standards (selected)
Normative references include ISO 8301, ISO 8302, ISO 23993, ISO 13787, ISO 29465, ISO 29466, ISO 29470, ISO 29767, ISO 16535, ISO 1663, ISO 18097 and ISO 12576‑1 - all relevant for testing, declared properties and conformity systems for thermal insulation products.