Overview
EN ISO 9288:2022 - Thermal insulation - Heat transfer by radiation - Vocabulary (ISO 9288:2022) is a terminology standard that defines the physical quantities and terms used in the field of thermal insulation when describing heat transfer by radiation. Prepared by ISO/TC 163 and adopted by CEN, this vocabulary standard replaces the earlier edition and provides a common, authoritative language for radiative heat-transfer concepts used in building physics, materials testing and thermal design.
Key topics
The standard covers concise, technical definitions and relationships for concepts including:
- Thermal radiation and heat transfer by radiation (scope and spectral relevance)
- Spectral versus total quantities: spectral radiation, spectral radiance, spectral intensity, spectral radiant heat flow rate
- Directional and hemispherical descriptions: directional radiation, hemispherical radiation, radiance, intensity
- Surface and medium classifications: opaque medium vs semi‑transparent medium and their radiative behaviors
- Radiative flux and density measures: radiant heat flow rate (Φ), radiant density of heat flow rate (q), including forward and backward components
- Combined conduction and radiation concepts for semi‑transparent materials and experimental determination methods (e.g., guarded hot plate, heat flow meter)
Practical applications
EN ISO 9288:2022 is a foundational reference for professionals who need consistent terminology when working with radiative heat transfer in thermal insulation contexts. Typical uses include:
- Writing and interpreting test methods and lab reports for insulation materials (manufacturers, test laboratories)
- Developing or applying building thermal-performance models where radiative exchanges are important (building physicists, energy modelers)
- Specifying or assessing radiative properties of surfaces and semi‑transparent materials in HVAC, façade and glazing design (engineers, architects)
- Harmonizing standards and regulatory documents where precise radiative terms avoid ambiguity (standards bodies, regulators)
By standardizing definitions such as radiance, spectral radiance and semi‑transparent medium, EN ISO 9288:2022 improves clarity across testing, simulation and specification workflows.
Related standards
EN ISO 9288:2022 is intended to be used alongside other thermal insulation vocabularies and methods, for example:
For authoritative implementation in Europe, the ISO text has been endorsed as EN ISO 9288:2022 by CEN and is to be adopted as a national standard by CEN member bodies.