Overview
IEC GUIDE 117:2010 - Electrotechnical equipment - Temperatures of touchable hot surfaces is a non‑mandatory IEC guide that provides systematic guidance for assessing burn risks from contact with hot touchable surfaces of electrical and electronic equipment. The Guide establishes how to determine surface temperature limits, describes maximum contact periods, and presents curves of maximum temperature versus contact time for different materials and surface textures. It is intended to inform technical committees when they set product standard limits and to support manufacturers and safety engineers in product risk assessments.
Key Topics and Requirements
- Risk assessment procedure: Step‑by‑step approach covering identification of touchable parts, task analysis, measurement and comparison with burn thresholds.
- Identification of surfaces: Distinguishes between touchable surfaces, hot functional surfaces, adjacent surfaces, and handles/control knobs - each treated differently for temperature limits.
- Contact period and burn threshold: Describes how to select maximum likely contact durations and the corresponding burn thresholds (surface temperature that separates no‑burn from superficial burn for a given contact period).
- Material and surface effects: Provides temperature vs. contact‑time curves and discusses the influence of material thermal properties, texture and coatings on burn risk.
- Measurement and documentation: Guidance on measuring surface temperature under specified conditions and documenting results for standards or conformity assessment.
- Annexes: Include normative and informative material - burn threshold data (Annex A), scientific background (Annex B), thermal properties of selected materials (Annex C) and example protective measures (Annex D).
- Reference: Builds on ergonomics standards such as ISO 13732‑1 for assessment methods.
Practical Applications - Who Uses This Standard
- Standards committees / technical committees: Use the Guide to set consistent surface temperature limits in product standards.
- Manufacturers and product designers: Apply the guidance during design and risk assessment to ensure touchable surfaces meet safety expectations.
- Safety and compliance engineers: Use the curves, contact‑time methodology and measurement guidance for hazard analyses and technical files.
- Test laboratories and certification bodies: Use the Guide when evaluating surface temperatures and documenting conformity for consumer appliances, industrial equipment, heating devices, luminaires, office machines and hand‑held tools.
Related Standards
- ISO 13732‑1: Ergonomics of the thermal environment - methods for assessing human responses to contact with surfaces (referenced normative document).
- CENELEC Guide 29: Source of original work adapted in this IEC Guide.
IEC GUIDE 117 is a practical resource for anyone involved in limiting burn risk from hot surfaces - providing structured methods, material‑specific data and documentation practices to support safe electrotechnical product design and standardization.