ISO 18640-1-2018 PDF

Full title and description

Protective clothing for firefighters — Physiological impact — Part 1: Measurement of coupled heat and moisture transfer with the sweating torso. This standard specifies a laboratory test method using a sweating torso to characterise coupled heat and moisture transfer properties of fabric assemblies and, optionally, complete ensembles to support thermo‑physiological assessment and material/garment optimisation for firefighting PPE.

Abstract

This document provides a test method for evaluating the physiological impact of protective fabric ensembles and potentially protective clothing ensembles in a series of simulated activities under defined ambient conditions. It characterises dry thermal insulation, cooling properties during average metabolic activity, moisture management (dry and wet heat transfer) and drying behaviour. Measurements are normally performed on fabric samples representing a garment or ensemble, with optional testing on more complex assemblies or ready‑made garments. The method is intended to describe thermo‑physiological impact but not to predict heat‑stress risk under real fire conditions; results can be used as inputs to risk assessment and to optimise material and garment selection.

General information

• Status: Published (confirmed after systematic review).
• Publication date: 29 May 2018.
• Publisher: International Organization for Standardization (ISO).
• ICS / categories: 13.340.10 (Protective clothing).
• Edition / version: Edition 1 (2018); amendment ISO 18640-1:2018/Amd 1:2019 exists.
• Number of pages: 37 pages.

All items above are based on the official ISO publication information and the subsequent amendment record.

Scope

Specifies a laboratory test procedure using a sweating torso apparatus to measure coupled heat and moisture transfer characteristics of fabrics and fabric assemblies representative of firefighter garments. The method covers measurement of thermal insulation, evaporative cooling and drying behaviour across a series of simulated activity phases in controlled ambient conditions. It may be applied to fabric samples, to fabric assemblies with underwear and air layers, and optionally to ready‑made garments. The standard is intended to support thermo‑physiological characterisation and comparison of PPE options, but it is not a direct predictor of heat‑stress risk in real fire environments.

Key topics and requirements

• Use of a sweating torso test rig to simulate combined conductive/convective and evaporative heat transfer in controlled activity phases.
• Measurement and reporting of dry thermal insulation (clo‑equivalent behaviour) for fabric assemblies.
• Assessment of cooling properties and moisture management during simulated metabolic activity (wet and dry heat transfer).
• Evaluation of drying behaviour following wetting/ sweating phases to characterise moisture handling.
• Test specimen preparation rules and optional configurations (underwear, air layers, readymade garments) with guidance on when comparisons are valid.
• Reporting requirements and use of results as elements in thermo‑physiological assessment and product optimisation (not as a stand‑alone heat‑stress prediction for operational fire conditions).

Typical use and users

Used by manufacturers of firefighter protective clothing, independent testing laboratories, research organisations (e.g., human factors and materials labs), procurement bodies and standards committees to characterise and compare materials and garment designs with respect to thermo‑physiological performance. Results support material selection, ensemble design optimisation and inputs to workplace risk assessments and product development.

Related standards

Relevant companion and supporting documents include ISO 18640-2:2018 (Determination of physiological heat load caused by protective clothing worn by firefighters) and ISO 18640-1:2018/Amd 1:2019 (amendment to Part 1). Other related PPE and terminology documents for firefighters include ISO/TR 19591:2018 (standard terms and definitions for firefighter PPE) and various protective clothing test standards under ISO/TC 94/SC 14.

Keywords

firefighter protective clothing; sweating torso; physiological impact; heat transfer; moisture transfer; thermal insulation; evaporative cooling; PPE test method; thermo‑physiological assessment.

FAQ

Q: What is this standard?

A: ISO 18640-1:2018 is an international test method standard that defines how to measure coupled heat and moisture transfer properties of fabrics and fabric assemblies for firefighter protective clothing using a sweating torso apparatus.

Q: What does it cover?

A: It covers laboratory procedures, measurement parameters and reporting to characterise dry thermal insulation, cooling (evaporative) properties, moisture management and drying behaviour of fabric assemblies and, optionally, ready‑made garments under simulated activity phases. It is intended for characterisation and comparison, not for predicting heat‑stress in real fire incidents.

Q: Who typically uses it?

A: Manufacturers, test houses, research institutions, procurement/specification teams and standards bodies use this standard to evaluate and compare thermo‑physiological performance of PPE materials and garment designs.

Q: Is it current or superseded?

A: The standard was published on 29 May 2018 (Edition 1) and has an amendment issued in 2019; ISO records show it was reviewed and confirmed as current in 2024. Therefore the 2018 edition (with the 2019 amendment) remains the current published text.

Q: Is it part of a series?

A: Yes — ISO 18640 is a multipart deliverable addressing physiological impact of firefighter protective clothing; Part 1 is this sweating‑torso test method and Part 2 covers determination of physiological heat load caused by protective clothing worn by firefighters (ISO 18640-2:2018).

Q: What are the key keywords?

A: Firefighter PPE, sweating torso, thermal insulation, evaporative cooling, moisture management, thermo‑physiological assessment, heat and moisture transfer, test method.