EN ISO 5659:2026 PDF

Overview

EN ISO 5659:2026 - Plastics - Smoke Generation - Determination of Optical Density by a Single-Chamber Test (ISO 5659:2026) specifies a standardized test method for measuring smoke generation from the exposed surface of plastic specimens and composites. Developed by CEN and ISO, this standard applies to flat specimens up to 25 mm thick, positioned horizontally and exposed to defined levels of thermal irradiance, with or without a pilot flame, in a closed test chamber.

The optical density values obtained from this method are specific to the tested form and thickness and are not fundamental material properties. The standard is primarily intended for use in research and development, and fire safety engineering within a variety of settings such as buildings, rail vehicles, and ships. Results from this test method support comparative analysis and product development but are not designed to serve as a basis for regulatory ratings or building code compliance.

Key Topics

• Test Scope:

  • Measures smoke production from plastics and composites.
  • Specimens must have an essentially flat surface and a maximum thickness of 25 mm.
  • Testing is performed under controlled thermal irradiance levels (25 kW/m² and 50 kW/m²).
  • Can be performed with or without a pilot flame.

• Measurement Principle:

  • The specimen is exposed to radiant heat in a sealed chamber.
  • Optical density of the smoke produced is determined by measuring the attenuation of a calibrated light beam passing through the chamber.
  • Records the specific optical density as an indicator of smoke obscuration.

• Testing Conditions:

  • The method is sensitive to specimen geometry, surface orientation, and thickness.
  • Applicable to a wide range of plastics used in panels, coatings, laminates, and assemblies.
  • Not suitable for materials exceeding 25 mm in nominal thickness without modification.

• Relevance:

  • Focuses on loss of visibility due to smoke density.
  • Excludes considerations of smoke irritancy or toxicity.

Applications

• Fire Safety Engineering:

  • Used to assess and compare the smoke generation potential of plastics and composite materials in research settings.
  • Important for evaluating materials intended for environments where loss of visibility could pose a risk, such as in transportation vehicles (trains, ships), public buildings, and enclosed spaces.
  • Supports the selection of materials for safer product development in industries like construction, transportation, and electronics.

• Research and Development:

  • Assists in material selection and the design of plastic composites with reduced smoke output.
  • Guides innovation in creating fire-safe plastic materials for use in passenger environments and critical infrastructure.

• Product Benchmarking:

  • Provides manufacturers and engineers with a reliable method for comparative testing of material smoke generation under standardized conditions.
  • Facilitates quality control and performance validation during new material qualification or product lifecycle management.

Related Standards

• ISO 291: Plastics - Standard atmospheres for conditioning and testing, referenced for specimen preparation and conditioning.
• ISO 13943: Fire safety vocabulary, provides definitions for key fire testing terms.
• ISO 14934-3: Fire tests - Calibration and use of heat flux meters - Part 3: Secondary calibration method, relevant for apparatus setup.
• ISO/TS 3814: Parameters critical for the burning behavior of materials and composites.
• ISO 5659-2:2017: Superseded by EN ISO 5659:2026, earlier version focusing on similar smoke generation measurements.

Note: The test method specified by EN ISO 5659:2026 ensures consistent and repeatable measurement of smoke optical density, but it is not intended for determining building code compliance or predicting actual fire smoke behavior. For comprehensive fire risk assessment, consult complementary standards and fire testing methodologies.

Keywords: EN ISO 5659:2026, plastics smoke generation, optical density test, fire safety engineering, single-chamber smoke test, material testing standards, loss of visibility, standardized fire testing, CEN, ISO, plastic composites fire behavior.