Smoke Density Test

Smoke Density Test

Alfa Chemistry provides you with smoke density testing services to help you make progress in the research of flame retardant mechanism of non-metallic materials, smoke emission testing, etc., including the samples you send for testing or the samples of flame retardant materials developed in cooperation with us.


Test Content

Test Range

The smoke density test can be used to study the mechanism of action of flame retardants and detect the smoke emission of non-metallic materials. For example, evaluate the light absorption curve and the smoke density rating (SDR) calculated from the light absorption value. In addition, smoke density testing services can be used to meet various flame retardant standards and laws and regulations during the development of new flame retardant products.

Test Principle

The material burns in the smoke box to generate smoke, and the solid dust in the smoke reflects the light passing through the smoke box, resulting in the loss of luminous flux. The smoke density is evaluated by measuring the change in luminous flux, thereby determining the degree to which the material may release smoke under the conditions of combustion and decomposition.

Smoke Density TestSchematic diagram of smoke density test [1]

Common Test Standards

At Alfa Chemistry, experienced materials chemists will recommend and select appropriate test standards for you based on customer needs and specific products.

  • ISO 5659-2
  • Plastics - Smoke generation - Part 2: Determination of optical density by single-chamber test

  • ASTM E 662
  • Standard Test Method for Specific Optical Density of Smoke Produced by Solid Materials

Important Test Parameters

  • Specific Optical Density at 1.5 min - Ds (1.5)
  • Specific Optical Density at 4.0 min - Ds (4.0)
  • Maximum Specific Optical Density - Dm
  • Corrected Maximum Specific Optical Density - Dm (corr)
  • Clear Beam Correction Factor – Dc

Why Choose Alfa Chemistry?

Experienced team of materials chemists

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Fast turnaround times and great prices

Comprehensive and systematic testing and analysis services

Research Information

Smoke Density Test for Coatings

Long Yan et al. synthesized a new type of phosphorus-containing boron flame retardants (PPEAs) and applied them to transparent flame retardant coatings for wood substrates. In this work, smoke density tests show that the introduction of polyethylene glycol borate (PEG-BA) has a good synergistic effect on reducing the smoke generation of coatings, while the excessive PEG-BA content can weaken this synergy effect.

Light absorption curve (a) and smoke density grade value (b) of flame retardant coatingsLight absorption curve (a) and smoke density grade value (b) of flame retardant coatings [2]

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  1. Sung Chan Kim. (2013). "Uncertainty Analysis of the Optical Smoke Density Measurement through the Doorway in a Compartment Fire," Fire Science and Engineering 27(2).
  2. Long Yan, et al. (2019). "Effects of polyethylene glycol borate on the flame retardancy and smoke suppression properties of transparent fire-retardant coatings applied on wood substrates," Progress in Organic Coatings 135, 123-134.
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