ISO 14505-4-2021 PDF

Full title and description

ISO 14505-4:2021 — Ergonomics of the thermal environment — Evaluation of thermal environments in vehicles — Part 4: Determination of the equivalent temperature by means of a numerical manikin. This part of the ISO 14505 series specifies a predictive, numerical-manikin–based method to determine the equivalent temperature for assessing thermal comfort in vehicle interiors, providing a computational alternative to physical thermal manikins for simulation and design purposes.

Abstract

ISO 14505-4:2021 gives guidelines for extending the equivalent temperature concept to predictive applications and defines a standard numerical-manikin method for calculating equivalent temperature in vehicle cabins. The document sets out model geometry, boundary conditions, required input data, solution approach and recommended validation/verification practices so that numerical simulations can be used consistently to assess passenger thermal comfort and support vehicle HVAC design and evaluation.

General information

• Status: Published / Current
• Publication date: 15 September 2021
• Publisher: International Organization for Standardization (ISO)
• ICS / categories: 13.180 (Ergonomics); 43.020 (Road vehicles — General)
• Edition / version: Edition 1 (2021)
• Number of pages: 44

Scope

This standard provides a standardised prediction method using a simulated numerical manikin to determine the equivalent temperature for thermal comfort assessment in vehicles. It covers the rationale for extending the equivalent temperature definition to predictive (numerical) use, prescribes the numerical-manikin concept and geometry, defines required environmental and occupant-related inputs, sets out calculation steps and reporting requirements, and gives guidance on validation and limitations of the predictive method. The method is intended for vehicle interior applications and similar confined spaces with asymmetric thermal conditions.

Key topics and requirements

• Definition and extension of the equivalent temperature concept for predictive (numerical) assessment.
• Specification of a simulated numerical manikin model (geometry, segment definitions, surface properties).
• Required environmental inputs: air temperature distribution, radiant temperatures, air velocity, humidity and boundary conditions.
• Numerical solution approach and recommended discretisation/meshing and solver considerations for reproducible results.
• Validation and verification: comparison with thermal manikin measurements and experimental data, uncertainty considerations.
• Reporting requirements: how to document inputs, assumptions, results and limitations for consistent interpretation.
• Limitations and recommended application domains (vehicle cabins and similar confined spaces; not a general-purpose human thermal physiology model).

Typical use and users

Primary users include vehicle OEMs, thermal and HVAC system engineers, CAE/simulation specialists, ergonomic researchers, test laboratories and regulatory or standards bodies involved in vehicle climate performance. Typical uses are early-stage design and evaluation of vehicle HVAC systems, virtual prototyping of cabin thermal performance, support for physical manikin or human-subject testing, and comparative assessments of HVAC or cabin design changes without the need for full physical testing.

Related standards

ISO 14505-2 (Determination of equivalent temperature), ISO/TS or ISO/FDIS 14505-1 (principles and methods for assessment of thermal stress), ISO 14505-3 (evaluation of thermal comfort using human subjects), and other ergonomics/thermal-environment standards such as ISO 7730 (thermal comfort — PMV/PPD methods) and ISO 7243 (assessment of heat stress using WBGT). National adoptions and related EN/BS adoptions of ISO 14505 parts may also be available.

Keywords

equivalent temperature, numerical manikin, thermal manikin, vehicle HVAC, thermal comfort, ergonomics, cabin thermal evaluation, predictive simulation, ISO 14505, CAE validation

FAQ

Q: What is this standard?

A: ISO 14505-4:2021 is an international standard that defines a numerical-manikin–based method for determining the equivalent temperature used to assess thermal comfort inside vehicle cabins.

Q: What does it cover?

A: It covers the extension of the equivalent temperature concept to predictive numerical use, prescribes a simulated numerical manikin model and inputs, outlines solution and reporting practices, and gives guidance on validation and limitations specific to vehicle interior applications.

Q: Who typically uses it?

A: Vehicle manufacturers, HVAC and thermal system engineers, CAE/simulation teams, ergonomic researchers, test labs and standards bodies use it for virtual thermal comfort assessment and to support or replace certain physical tests.

Q: Is it current or superseded?

A: As published in September 2021, ISO 14505-4:2021 is the current edition for Part 4. Users should check with their national standards body or ISO for any later amendments or revisions when needed for compliance.

Q: Is it part of a series?

A: Yes — ISO 14505 is a multi-part series addressing evaluation of thermal environments in vehicles. Other parts include guidance on principles and methods (Part 1), equivalent temperature measurement (Part 2), and human-subject assessment (Part 3).

Q: What are the key keywords?

A: Equivalent temperature; numerical manikin; thermal comfort; vehicle cabin; HVAC; ergonomics; simulation; ISO 14505.