ISO 5659-2-2017 PDF

Full title and description

ISO 5659-2:2017 — Plastics — Smoke generation — Part 2: Determination of optical density by a single‑chamber test. This part of ISO 5659 specifies a laboratory method (single closed chamber) for measuring the optical density of smoke produced from exposed surfaces of flat specimens of plastics (up to 25 mm thickness) under defined thermal irradiance and optional pilot‑flame conditions; results are specific to the specimen form and thickness tested and are intended mainly for research, development and fire‑safety engineering purposes rather than as building‑code ratings.

Abstract

ISO 5659-2:2017 describes a single‑chamber (closed cabinet) photometric test to determine smoke optical density generated from plastics when exposed horizontally to specified irradiance levels (commonly 25 kW/m² and 50 kW/m²) with or without a pilot flame. The standard clarifies that measured optical‑density values are specific to the specimen configuration and that the test does not predict smoke behaviour under all real fire conditions or address irritancy effects on the eye.

General information

• Status: Withdrawn (replaced by consolidated ISO 5659:2026).
• Publication date: May 2017 (ISO 5659‑2:2017, Edition 4).
• Publisher: International Organization for Standardization (ISO).
• ICS / categories: 13.220.40 (Ignitability and burning behaviour of materials and products); 83.080.01 (Plastics in general).
• Edition / version: Edition 4 (2017).
• Number of pages: 49 pages (as published in 2017).

Scope

The standard applies to measuring smoke production from the exposed surface of flat specimens (not exceeding 25 mm thickness) of plastics or assemblies, placed horizontally in a closed chamber and subjected to defined radiant heat fluxes (notably 25 kW/m² and 50 kW/m²). It covers apparatus, specimen preparation, test procedure, measurement and reporting of optical‑density values, and notes the limitations of applicability to real‑fire scenarios.

Key topics and requirements

• Single‑chamber (closed cabinet) photometric method for specific optical density (smoke obscuration) measurement.
• Specimen geometry and orientation: essentially flat specimens, horizontal placement, maximum thickness typically 25 mm.
• Thermal irradiance levels specified (commonly 25 kW/m² and 50 kW/m²) and optional pilot‑flame application.
• Results expressed as optical‑density metrics (e.g., specific optical density, Ds and maximum values); values are specific to the specimen form/thickness and test conditions.
• Intended uses and limitations: research, product development and fire‑safety engineering; not intended as a direct basis for code ratings or to predict smoke behaviour in all fire scenarios; irritancy effects are excluded.
• Calibration, clear‑beam correction and reporting rules for reproducible results in laboratory conditions.

Typical use and users

Used by fire‑testing laboratories, materials scientists, plastics and polymer manufacturers, fire‑safety engineers, rail/air/marine materials approval teams, and R&D groups evaluating smoke production characteristics of materials and assemblies. Test reports inform product development, material selection and engineering assessments but should be interpreted alongside other fire‑performance data.

Related standards

Relevant and commonly cross‑referenced standards include: ISO 5659 (consolidated edition published January 2026, which supersedes ISO 5659‑2:2017); ISO 5659‑1 (guidance on optical‑density testing, historic/withdrawn versions); ISO 5660 series (cone calorimeter — heat release and smoke production rate); and ASTM test methods addressing specific optical density/smoke chamber measurement (for example ASTM E662 and related ASTM methods). These documents are used together when evaluating reaction‑to‑fire and smoke characteristics in different regulatory and industry contexts.

Keywords

smoke generation; optical density; smoke chamber; single‑chamber test; plastics; NBS smoke density chamber; Ds (specific optical density); irradiance (25 kW/m², 50 kW/m²); pilot flame; fire testing; ISO 5659.

FAQ

Q: What is this standard?

A: ISO 5659-2:2017 is the fourth edition (2017) of the ISO test method for determining the optical density of smoke produced by plastics in a single closed chamber under specified heat flux and optional pilot‑flame conditions. The document has been withdrawn and superseded by the consolidated ISO 5659:2026.

Q: What does it cover?

A: It defines apparatus, specimen preparation, irradiance conditions (notably 25 kW/m² and 50 kW/m²), photometric measurement, data corrections and reporting for specific optical density (smoke obscuration) in a closed chamber; it also states limitations regarding real‑fire prediction and irritancy effects.

Q: Who typically uses it?

A: Fire‑test laboratories, materials manufacturers (plastics), product R&D teams, fire‑safety engineers, and approval bodies in transport and building sectors. Test results are used for development and engineering decisions rather than direct code classification without additional context.

Q: Is it current or superseded?

A: ISO 5659-2:2017 has been withdrawn. It was superseded by the consolidated ISO 5659:2026 (published 27 January 2026), which incorporates and replaces the earlier part‑based documents. For current normative requirements and the latest test text, refer to ISO 5659:2026.

Q: Is it part of a series?

A: Historically yes — ISO 5659 was a multipart series (Part 1 guidance, Part 2 single‑chamber test, etc.). The series has been consolidated into ISO 5659:2026; legacy part numbers (e.g., ISO 5659‑1, ISO 5659‑2) appear in historical references.

Q: What are the key keywords?

A: Smoke generation, optical density, smoke chamber, specific optical density (Ds), plastics, single‑chamber test, irradiance, pilot flame, NBS smoke density chamber.