EN ISO 9920:2009 PDF

Ergonomics of the thermal environment - Estimation of thermal insulation and water vapour resistance of a clothing ensemble (ISO 9920:2007, Corrected version 2008-11-01)

Title (English):

EN ISO 9920:2009

Ergonomics of the thermal environment - Estimation of thermal insulation and water vapour resistance of a clothing ensemble (ISO 9920:2007, Corrected version 2008-11-01)

Document status:: Active
Format:: Electronic (PDF)
Number of pages:: 114
Publication date:: June 3, 2009
Edition:: CEN EN 9920 edition 2 version 1
ICS:: 13.040.20

Document language:

enru

Delivery time:1–7 days

Price:148 €

Description (English):

ISO 9920:2007 specifies methods for estimating the thermal characteristics (resistance to dry heat loss and evaporative heat loss) in steady-state conditions for a clothing ensemble based on values for known garments, ensembles and textiles. It examines the influence of body movement and air penetration on the thermal insulation and water vapour resistance. It does not deal with other effects of clothing, such as adsorption of water, buffering or tactile comfort, take into account the influence of rain and snow on the thermal characteristics, consider special protective clothing (water-cooled suits, ventilated suits, heated clothing), or deal with the separate insulation on different parts of the body and discomfort due to the asymmetry of a clothing ensemble.

Technical details

Technical committee: CEN/TC 122 - Ergonomics
SKU: EN ISO 9920:2009

Abstract

Overview

EN ISO 9920:2009 (ISO 9920:2007, Corr. 2008-11-01) - Ergonomics of the thermal environment - specifies methods to estimate the thermal insulation and water vapour resistance of a clothing ensemble. The standard treats clothing thermal characteristics under steady‑state conditions and links garment and textile data to ensemble behaviour. It was adopted as EN ISO 9920:2009 and transposed by SIST in 2010.

Key topics and technical requirements

Scope and limits
- Estimates resistance to dry heat loss (thermal insulation, I) and evaporative heat loss (vapour resistance) for clothing ensembles.
- Applies to steady‑state conditions only; excludes buffering, adsorption, rain/snow effects, special active protective clothing, and separate local body-part insulation.
Definitions and units
- Thermal insulation defined as resistance to dry heat loss (m²·K·W⁻¹) and commonly expressed in clo (1 clo = 0.155 m²·K·W⁻¹).
Estimation methods
- Use of tables and measured values for known garments and ensembles (normative tables provided).
- Procedures for calculating ensemble insulation from individual garments and for correcting small composition differences.
- Estimation of clothing area factor and boundary air layer insulation.
Vapour resistance
- Methods to estimate clothing water vapour resistance from tables and from relations with dry heat resistance.
Effects of motion and air
- Corrections for body movement and air penetration/velocity on both thermal insulation and vapour resistance.
- Guidance for activities other than walking and for relative air velocities.
Annexes
- Normative tables for ensembles, garments and vapour permeability (Annexes A–C).
- Informative guidance on measurements with thermal manikins and human subjects (Annexes D–E) and additional explanatory material (Annexes F–H).

Practical applications and users

Use the standard when evaluating thermal stress, thermal comfort and safety:
- Occupational health & safety assessments (cold stress, heat stress).
- HVAC and indoor environmental design (thermo‑ergonomics, PMV/PPD evaluations).
- Protective clothing and PPE selection (non‑specialized garments).
- Apparel and textile R&D for thermal performance.
- Research using thermal manikins and human subject trials.
Commonly applied in conjunction with thermal indices and standards such as ISO/TR 11079 (IREQ), ISO 7730 (PMV/PPD) and ISO 7933 (predicted heat strain).

Related standards

ISO/TR 11079 - Insulation index (IREQ) for cold environments
ISO 7730 - Thermal comfort (PMV/PPD)
ISO 7933 - Predicted heat strain

This standard is essential for ergonomists, thermal comfort consultants, clothing designers, occupational hygienists and researchers needing consistent, validated methods to estimate clothing thermal and evaporative resistance.

Related standards

Standards mentioned in the description

Abstract

Overview

Key topics and technical requirements

Scope and limits
- Estimates resistance to dry heat loss (thermal insulation, I) and evaporative heat loss (vapour resistance) for clothing ensembles.
- Applies to steady‑state conditions only; excludes buffering, adsorption, rain/snow effects, special active protective clothing, and separate local body-part insulation.
Definitions and units
- Thermal insulation defined as resistance to dry heat loss (m²·K·W⁻¹) and commonly expressed in clo (1 clo = 0.155 m²·K·W⁻¹).
Estimation methods
- Use of tables and measured values for known garments and ensembles (normative tables provided).
- Procedures for calculating ensemble insulation from individual garments and for correcting small composition differences.
- Estimation of clothing area factor and boundary air layer insulation.
Vapour resistance
- Methods to estimate clothing water vapour resistance from tables and from relations with dry heat resistance.
Effects of motion and air
- Corrections for body movement and air penetration/velocity on both thermal insulation and vapour resistance.
- Guidance for activities other than walking and for relative air velocities.
Annexes
- Normative tables for ensembles, garments and vapour permeability (Annexes A–C).
- Informative guidance on measurements with thermal manikins and human subjects (Annexes D–E) and additional explanatory material (Annexes F–H).

Practical applications and users

Use the standard when evaluating thermal stress, thermal comfort and safety:
- Occupational health & safety assessments (cold stress, heat stress).
- HVAC and indoor environmental design (thermo‑ergonomics, PMV/PPD evaluations).
- Protective clothing and PPE selection (non‑specialized garments).
- Apparel and textile R&D for thermal performance.
- Research using thermal manikins and human subject trials.
Commonly applied in conjunction with thermal indices and standards such as ISO/TR 11079 (IREQ), ISO 7730 (PMV/PPD) and ISO 7933 (predicted heat strain).

Related standards

ISO/TR 11079 - Insulation index (IREQ) for cold environments
ISO 7730 - Thermal comfort (PMV/PPD)
ISO 7933 - Predicted heat strain

EN ISO 9920:2009 PDF

Technical details

Abstract

Overview

Key topics and technical requirements

Practical applications and users

Related standards

Related standards

Abstract

Overview

Key topics and technical requirements

Practical applications and users

Related standards

Related standards

Ergonomics of the thermal environment — Estimation of thermal insulation and water vapour resistance of a clo…

Evaluation of cold environments — Determination of required clothing insulation (IREQ)

Ergonomics of the thermal environment. Analytical determination and interpretation of thermal comfort using c…

Ergonomics of the thermal environment - Analytical determination and interpretation of heat stress using calc…