Determination of fire code rating (BKZ)
according to the Association of Swiss Canton Fire Insurance Companies (VKF)
The fire code rating (BKZ x.y) is composed of two individual tests:
- Flammability rating (x):
- Textiles, low flammability according to SN 198898:1987 [en] (withdrawn date 1999-07-01)
- Building materials, basic test according to VKF
- Determination of smoke density according to VKF (y)
In our lab, we can test textiles for classifications 5.3, 5.2, and 5.1. For building materials the classifications 5.3, 5.2 or 5.1 // 4.3, 4.2 or 4.1 // 3.3, 3.2 or 3.1
Pretreatment:
Textiles whose fibers are not of low flammability and whose burning behavior can therefore be influenced by cleaning treatments are tested in their original condition and after six cleaning treatments by the care instructions. Classification takes place when the flammability grade 5 is reached in the original and cleaned condition.
Color selection:
If a material is available in different color versions, DIN 4102-16:2015-09 applies to the selection of the color variants (white or lightest, red or closest, black or darkest) to be tested. In the case of positive results, the result is valid for all colors.
Determination of the burning and smoldering behavior of textiles according to SN 198898:1987
The acclimatized samples are suspended vertically in a combustion box and brought into contact with a propane gas flame from a burner positioned at 30° to the vertical for 3s and 15s at the lower edge.
Basic test according to VKF
The acclimatized samples are suspended vertically in a combustion box and brought into contact with a propane gas flame from a burner positioned at 45° to the vertical for 15s at the lower edge.
Determination of the Smoke Density in accordance with VKF
A defined test specimen is exposed in a standardized test apparatus with a defined air flow rate and a defined flame exposure until it burns off. The maximum of the obscuration (light absorption) produced by the smoke is measured by photometry.
Relevant standards
- SN 198898:1987 Bestimmung des Brenn- und Glimmverhaltens textiler Flächengebilde, Kantenzündung vertikal
- «Wegleitung für Feuerpolizeivorschriften: Baustoffe und Bauteile», Teil B: Prüfbestimmungen, Ausgabe 1988 (mit Nachträgen 1990, 1994, 1995 und 2005) der Vereinigung Kantonaler Feuerversicherungen (VKF), Bundesgasse 20, Postfach 8576, CH-3001 Bern.