The Swiss Fire code (BKZ) is made up of the in the tests ascertained flammability class (first number) and the smoke level (second number), for example, BKZ 4.3.
According to EN 1350-1, combustible materials may in a transitional solution be assigned to VKF classifications. The mapping tables are published by VKF Association of Cantonal Fire Insurers.
The tables provide a simplified application for the fire and smoke behavior and for burning droplets / particles of combustible materials on the basis of national fire protection directive „use combustible materials“ and can only be used in consultation with the cantonal and municipal fire authorities, however, they are usually informally recognized.
EN-classification E corresponds VKF-classification 3
EN-classification s3 corresponds VKF-classification 1
The fire code is therefore given as: BKZ 3.1
Literature and Source: VKF Association of Cantonal Fire Insurers
Links:
http://www.praever.ch/de/bs/reg/info/klassierung/Seiten/default.aspx