All organic substances – including plastics – are combustible. A material’s fire performance is essentially described by the following parameters:
- flame spread
- heat release
- smoke development (smoke density and toxicity of the fire gases)
- surface-to-mass ratio of the combustible materials
In addition to being influenced by the material-inherent components, fire performance is additionally determined by associated factors, such as
- type of storage
- quantity of material
- thermal pre-treatment
- exposure time and intensity of the ignition source, etc.
In view of the complexity of the influencing variables, it is not possible to provide a universally valid description of the fire performance of Desmopan® grades. A large number of standards and regulations describe what are frequently highly specific applications and test procedures, but these do not have any absolute information value. In case of doubt, please contact our technical product support team, who will be pleased to provide advice and assistance at all times. A number of particularly important and widely-used fire tests are listed below. This list does not claim to be exhaustive.
UL 94 (Underwriters Laboratories)
Desmopan® grades without additives essentially attain an HB classification; a number of grades without flame retardants also achieve a V2 classification. We can send you Yellow Cards for a number of grades on request.
ISO 4589 (ASTM D 2863; Lowest Oxygen Index; LOI value)
The Lowest Oxygen Index (LOI) indicates the minimum oxygen concentration that must be present in an oxygen/nitrogen mixture for a material to burn. To measure the LOI, a mixture of O2/N2 with a decreasing O2 content is fed to a burning specimen until the flame extinguishes. Desmopan® grades attain values of between 18 and 24 %.
ISO 871 (ASTM D 1929; external ignition; self-ignition)
These tests involve exposing a sample to a pilot flame in a hot-air oven or determining the self-ignition temperature of the sample in the hot-air oven. This method can be used to compare different plastics under identical conditions, but it does not provide a generally-valid statement on combustibility or burning rate. Desmopan® grades have an external ignition temperature of between 350 and 400 °C, and a self-ignition temperature of between 450 and 600 °C.
Burning behavior to FMVSS 302
Various Desmopan® grades have been tested to test standard FMVSS 302. The requirements of the standard have always been satisfied. According to FMVSS 302, burning rates of up to 101.6 mm/min are permitted. The burning rates measured were between 15 and 65 mm/min, depending on the Desmopan® grade, the Shore hardness and the wall thickness. We thus assume that all Desmopan® grades satisfy the requirements of test standard FMVSS 302. Please contact us if you have any further questions in this respect.
DIN EN 50267-2-2 (corrosiveness of combustion gases)
All non-modified Desmopan® grades meet the requirements of this standard, which relates to the corrosiveness of the combustion gases.
Glow wire test to IEC 60695-2-12 (DIN EN 60695-2-12)
The material fulfils the requirements if none of the three specimens has a flaming combustion time of more than 30 sec. and if the underlying tissue paper is not ignited by flaming droplets. Values for this test are available for a number of Desmopan® grades.
Glow wire test to IEC 60695-2-13 (DIN EN 60695-2-13)
This specifies a temperature that is 25 °C higher than the highest temperature prevailing at the tip of the glowing wire which does not lead to ignition in three successive tests. (ignition is defined as a flame that is visible for more than 5 sec.) Values for this test are available for a number of Desmopan® grades. Additives can influence the fire performance of Desmopan® grades. Further details may be found in our Safety Data Sheets.
The Thermoplastics Testing Center (TTC) will carry out the following fire tests for you:
|Flammability UL 94 HB
|Flammability UL 94 V
|Flammability UL 94-5V
|Electrical ignition source
in-house standard (rapid ash)