ASTM E681 Test for Flammability Concentration Limits of Chemicals

EUROLAB laboratory provides testing and compliance services within the scope of ASTM E681 standard. This standard covers the determination of flammability lower and upper concentration limits of chemicals that have sufficient vapor pressure to form flammable mixtures in air at atmospheric pressure at test temperature.

This test method can be used to determine these limits in the presence of inert dilution gases. Oxidants stronger than air should not be used.

The lower flammability limit (LFL) and upper flammability limit (UFL) are sometimes referred to as lower explosion limit (LEL) and upper explosion limit (UEL), respectively. However, because the terms LEL and UEL are also used to refer to concentrations outside the limits defined in this test method, the definitions need to be closely scrutinized when reporting or using LEL and UEL values.

This test method is based on electrical ignition and visual observations of flame propagation. Users may experience problems if flames are difficult to observe (for example, uneven propagation or insufficient luminescence in the visible spectrum), if the test material requires large ignition energy, or if the material has large extinguishing distances.

It provides a modified test method for materials with large quenching distances (such as certain amines, halogenated materials and the like) that may be difficult to ignite.

In other situations where strong ignition sources (such as direct flame ignition) are considered reliable, use a test method that uses a higher energy ignition source in a sufficiently large pressure chamber (for example, similar to the methods in Test Method E2079). measuring the limiting oxygen concentration) may be more appropriate. In this case, expert advice may be necessary.

Flammability limits depend on test temperature and pressure. This test method is limited to a local ambient pressure or lower initial pressure with a practical lower pressure limit of approximately 13 kPa (100 mm Hg). The maximum practical operating temperature of this equipment is approximately 150°C.

Values ​​stated in SI units should be accepted as standard. No other units of measurement are included in this standard.

This test method should be used to measure and describe the properties of materials, products, or assemblies in response to heat and flame under controlled laboratory conditions and assemblies under actual fire conditions of materials, products, or assemblies. However, the results of this test method can be used as elements of a fire risk assessment that takes into account all factors relevant to the fire hazard assessment of a particular end use.

EUROLAB assists manufacturers with ASTM E681 test compliance. Our test experts, with their professional working mission and principles, provide you, our manufacturers and suppliers, the best service and controlled testing process in our laboratories. Thanks to these services, businesses receive more effective, high-performance and quality testing services and provide safe, fast and uninterrupted service to their customers.