IEC 60695-2-12:2021

Overview

IEC 60695-2-12:2021 defines a standardized glow-wire flammability index (GWFI) test method for solid electrical insulating materials and other solid materials used in electrotechnical products. The GWFI is the highest glow-wire temperature at which a material does not ignite - or, if ignition occurs, the specimen self-extinguishes within 30 seconds after removal of the glow‑wire, is not totally consumed, and any molten drips do not ignite the wrapping tissue. This third edition (2021) is a technical revision and introduces updated terms and definitions related to times and durations that affect test application.

Key topics and requirements

• Scope and purpose: Materials test for flammability ranking under controlled laboratory conditions to support material preselection and safety assessments.
• Test definition: Clear criteria for GWFI including ignition, self‑extinguishing time (30 s), residue and molten drip behavior.
• Specimen and conditioning: Requirements for preparation, dimensions, conditioning atmospheres and test conditions to ensure repeatable results.
• Apparatus and verification: Use of the glow‑wire apparatus and verification of the temperature‑measuring system (see IEC 60695-2-10 for apparatus details).
• Test procedure and observations: Initial and progressive test temperatures, observations to record (ignition, glow persistence, dripping), and measurement reporting.
• Result evaluation and reporting: How GWFI is determined from test runs and the required information for a compliant test report.
• Limitations: Emphasizes this is a laboratory materials test and not a standalone measure of full fire hazard under real fire conditions.

Applications

• Material selection and ranking for components and enclosures in electrical and electronic equipment.
• Preselection testing to reduce the scope of end‑product testing by providing objective material flammability data.
• Input to fire hazard assessments for designers, safety engineers and compliance teams evaluating resistance to overheated parts (e.g., bad connections, overloaded components).
• Used by test laboratories, certification bodies, manufacturers of insulating materials, and standards/technical committees preparing safety publications.

Who should use it

• Materials and polymer manufacturers seeking flammability characterization.
• Product designers and electrical equipment developers performing material preselection.
• Accredited testing laboratories and conformity assessment bodies.
• Technical committees and standards developers referencing basic safety test methods.

Related standards

• IEC 60695-2-10 - Glow‑wire apparatus and common procedures
• IEC 60695-2-13 - Glow‑wire ignition temperature (GWIT) for materials
• IEC 60695-1-30 - Preselection testing process guidance
• IEC 60695-2-11 - Glow‑wire test for end‑products
• IEC 60695-4, IEC Guide 104, ISO/IEC Guide 51 - complementary terminology and safety guidance

Keywords: IEC 60695-2-12, GWFI, glow-wire flammability index, glow‑wire test, fire hazard testing, electrical insulating materials, material preselection, flammability testing.