ISO 9920-2007 PDF

Full title and description

ISO 9920:2007 — Ergonomics of the thermal environment — Estimation of thermal insulation and water vapour resistance of a clothing ensemble. This International Standard gives methods, tables and guidance to estimate the thermal insulation (resistance to dry heat loss) and evaporative resistance (resistance to evaporative heat loss) of whole clothing ensembles, and addresses the influence of body movement and air penetration on those properties.

Abstract

ISO 9920:2007 specifies methods for estimating the thermal characteristics of a clothing ensemble in steady-state conditions using known values for individual garments, ensembles and textiles. It provides calculation procedures, correction factors and tabulated data to derive clothing insulation (Icl) and water vapour resistance (Ret) for ensembles and to account for effects of movement and air permeability. The standard excludes effects such as water adsorption, tactile comfort, the influence of rain/snow, special protective or actively conditioned clothing (e.g., water-cooled or heated suits), and detailed analysis of separate body-part insulation or discomfort from ensemble asymmetry.

General information

• Status: Published (confirmed by ISO review).
• Publication date: June 2007 (corrected version: October 2008).
• Publisher: International Organization for Standardization (ISO).
• ICS / categories: 13.180 (Ergonomics); 61.020 (Clothing).
• Edition / version: Edition 2 (2007), corrected English version 2008-10.
• Number of pages: 105.

Scope

Provides methods and tabulated data to estimate thermal insulation (Icl) and evaporative resistance (Ret) of complete clothing ensembles under steady-state conditions. It covers how to combine garment and textile data, how body movement and air penetration modify thermal and evaporative resistance, and how to apply correction factors and example calculations. It does not address transient wetting effects, rain/snow influence, special or actively conditioned protective clothing, adsorption/buffering or tactile comfort, nor does it provide a detailed allocation of insulation to separate body parts or address ensemble asymmetry discomfort.

Key topics and requirements

• Definition and units for clothing thermal insulation (Icl) and water vapour resistance (Ret).
• Procedures to estimate ensemble insulation from individual garment and textile values.
• Correction factors and methods to account for body movement and air penetration.
• Tabulated reference values for common garments, textiles and ensembles.
• Calculation examples and worked procedures for combining items into ensembles.
• Guidance on limitations, measurement comparability and appropriate use of estimated values.
• Clear statement of exclusions (rain, special protective clothing, transient wetting effects).

Typical use and users

Used by ergonomists, occupational health and safety professionals, thermal comfort and heat-stress assessors, HVAC engineers, clothing and protective-wear designers, sports-technical developers and researchers who need standardized estimates of clothing insulation and evaporative resistance for comfort, safety and thermal-model inputs.

Related standards

Associated and commonly used standards include ISO 7730 (thermal comfort — PMV/PPD), ISO 9886 (physiological measurements for thermal strain), ISO 7243 (heat stress using WBGT), ISO 11079 (cold environments and clothing assessment), ISO 7933 (heat stress evaluation), and national/adopted versions (for example EN ISO 9920). The earlier ISO 9920:1995 was withdrawn and replaced by this 2007 edition.

Keywords

thermal insulation, clothing insulation, Icl, water vapour resistance, Ret, clothing ensemble, evaporative resistance, thermal comfort, ergonomics, heat stress, clothing properties

FAQ

Q: What is this standard?

A: ISO 9920:2007 is an international standard that specifies methods and reference data to estimate the thermal insulation and water vapour resistance of a clothing ensemble for ergonomic and thermal-environment assessments.

Q: What does it cover?

A: It covers estimation procedures, correction factors for movement and air penetration, and tabulated garment/textile values to calculate ensemble Icl and Ret under steady-state conditions. It excludes rain/snow effects, special active protective clothing, adsorption/buffering effects and detailed per-body-part insulation analyses.

Q: Who typically uses it?

A: Ergonomists, occupational health and safety professionals, researchers in thermal physiology and comfort, clothing and protective-equipment designers, and HVAC/thermal-modelling engineers.

Q: Is it current or superseded?

A: The edition referenced here is Edition 2 published in June 2007 (with a corrected English text issued in October 2008). This edition replaced ISO 9920:1995 and, following ISO review cycles, has been maintained/confirmed by ISO (reviewed and confirmed as current in ISO’s review process).

Q: Is it part of a series?

A: It belongs to the family of ergonomics and thermal-environment standards developed under ISO/TC 159 (subcommittee SC 5) and is commonly used alongside other thermal-environment standards (for example ISO 7730, ISO 9886, ISO 7243 and ISO 11079) to assess comfort and heat/cold stress.

Q: What are the key keywords?

A: Key keywords are thermal insulation, clothing insulation (Icl), water vapour resistance (Ret), evaporative resistance, clothing ensemble, thermal comfort, ergonomics, heat stress.