EN ISO 11925-2 Reaction to Fire Tests - Flammability of Products in Direct Contact with Flame - Part 2: Single Flame Source Test

The standard "EN ISO 11925-2 Reaction to fire tests - Ignition of products in direct flame contact - Part 2: Single flame source test", which has its basis in a European standard and was subsequently published by the International Organization for Standardization (ISO), describes a test method for determining the ignitability of products by direct small flame impingement under zero impressed irradiance using vertically oriented samples.

The annexes of this standard are arranged as follows:

• Appendix A: Information on the sensitivity of this test method
• Appendix B: Information on testing non-flat end-use products
• Appendix C: Information on testing perforated end-use products

For the purposes of this standard, the following definitions apply in addition to the terms and definitions given in the “ISO 13943 Fire safety - Glossary” standard:

• Product: The material, element or component for which information is required.
• Essentially flat product: A product that has one of the following characteristics:
  • A planar open surface.
  • A planar exposed surface having surface irregularities uniformly distributed over the exposed surface. Provided that:
    • At least 50 percent of the surface of a representative square area of ​​250 mm x 250 mm lies at a depth of 6 mm from a plane taken from the highest points on the open surface, or
    • For a surface containing cracks, splits or holes, they shall not exceed 6,5 mm in width or 10 mm in depth, and the total area of ​​such cracks, splits or holes in the surface shall not exceed 30 percent of the representative 250 mm x 250 mm square area of ​​the open surface.
• Flaming droplets or particles: Material that separates from the sample during the fire test procedure and ignites the filter paper below the sample.
• Multilayer products: A product composed of two or more layers of different materials (may be significant or insignificant).
• Sustained flame: A flame that continues for more than 3 seconds.
• Ignition: Indicates the presence of sustained flames.

The test specimen shall be cut from a representative sample of the product to be tested using the templates specified in this standard. The test specimens shall have dimensions of 250 mm plus or minus 2 mm in length and 90 mm plus or minus 2 mm in width. Specimens normally 60 mm thick or less shall be tested using their full thickness. Specimens normally greater than 60 mm in thickness shall be cut down to 60 mm by cutting away the unexposed surface. If this reduction in specimen size is necessary, the cut surface shall not be exposed to flame. For products normally manufactured to a size smaller than the test specimen, a test specimen of a suitable size shall be produced specifically for testing.

When the product is not essentially a flat product, samples may be tested for their intended end use (e.g., pipe insulation). The product should be supplied in its entirety or in 250 mm long samples.

For each exposure condition, at least six representative samples of the product should be tested. Three samples should be cut longitudinally and three samples should be cut transversely. If a product being tested is asymmetrical throughout its thickness and both surfaces may be exposed to an ignition source, two samples should be tested on each surface to determine the critical impact point. A complete series of tests should be conducted to determine the critical impact point.

If a product has significantly different surface areas, but each of these distinct areas essentially meets the surface specifications of flat products, two tests should be performed at each flame impact point. The critical impact point should be determined. A full series of tests should be performed for the critical impact point. If a product is assembled with closed edges but can also be used with unprotected edges, tests should be performed on both closed and open specimens.

When using a substrate, specimens should be selected in accordance with ISO 14697 or EN 13238. Care should be taken when preparing test specimens to expose the bottom edges of materials applied to the substrates, as in practice the substrate may extend beyond the bottom of the material being tested and not be exposed itself. The configuration of the test specimen should reflect practical considerations such as substrate type and attachment to the substrate.

Test samples and filter papers must be conditioned in accordance with EN 13238 standard.

The EN ISO 11925-2 standard is important because it specifies a method for assessing the flammability of building products when exposed to a small flame, which is crucial for assessing fire safety. This standard is considered important for the following reasons:

• Fire safety assessment: Helps classify fire behavior by testing how easily materials ignite when exposed to direct flame. This is important for ensuring the safety of buildings and occupants by identifying materials that could contribute to the spread of fire.
• Regulatory compliance: Many countries and regions, particularly in Europe, use EN ISO 11925-2 as part of their building regulations. Compliance reduces risks in construction by ensuring that materials meet fire safety standards.
• Standardized testing: This standard provides a consistent and repeatable method for measuring flammability, enabling reliable comparison of materials across manufacturers and markets. This supports fair trade and quality assurance.
• Materials development: Manufacturers use the standard to develop and improve fire-resistant materials, ensuring products meet safety requirements before they are released to market.
• Risk reduction: This standard minimizes fire hazards in buildings by identifying materials that are prone to rapid ignition, helping architects, engineers, and regulators select safer materials.

In conclusion, the EN ISO 11925-2 standard is an important tool for ensuring fire safety and conscious material selection in construction and ultimately ensuring the safety of life and property.

Our organization, which has been supporting businesses across all sectors for years through a wide range of testing, measurement, analysis, and evaluation activities, boasts a strong team of employees who closely follow global developments in science and technology and are constantly improving themselves. In this context, we also provide testing services in accordance with the EN ISO 11925-2 Reaction to fire tests - Flammability of products in direct contact with flame - Part 2: Single flame source testing."