Classification of Flame spread for cables

There are 4 classifications for flame and fire retardant cables in Sweden, F1-F4 according to the swedish standard SS 424 14 75. For the class F1 there are no requirements for firespread whereas for class F4 it means that the cable can't spread the fire even though the cables are mounted together in a bunch.

   Description of test

Swedish   F1
European   -
IEC-   -
   The wire/cable is not self-extinguishing and do spread fire.
   Normally the wires and cables in this classification is only
   intended for installation in ground or in water.

Swedish   F2
European   EN 50265-2-1
IEC-   IEC 60332-1

   A single wire/cable is self-extinguishing and does not spread
   fire. Vertical test where a test sample of 600 mm is ignited. The
   flame is applied continuously for 1-8 minutes depending on the
   outer diameter. The fire damages shall be limited and the fire
   damages should not be greater then 50 mm from the lower
   edge of the top support.

Swedish   F3
European   HD 605-4.1.5
IEC-   -
   Single wire/cable or bunched cables which are self-extinguishing
   and do not spread fire. The cables are harder to ignite and do
   maintain fire less than F2. Vertical test where a test sample of
   850 mm is placed in a vertical steel pipe with openings for
   ventilation along the sides. A fluid is placed below the cable
   and ignited. The flame is applied continuously for 3-9 minutes
   depending on the outer diameter and cross-section. The fire
   damages shall be limited and no external fire damages shall
   exist on the part of the samples that are within 300 mm from
   the top edge.

Swedish   F4
European   EN 50266-2
IEC-   IEC 60332-3
   Cables bunched together which are self-extinguishing and do
   not spread fire. The cables are harder to ignite and do maintain
   fire less than F3. The test is carried out in a 4 meter high test
   chamber on test samples that are mounted vertically on a ladder.
   The samples must have a minimum length of 3,5 meters. The
   fire damages shall be limited and the fire damages should not
   have reached a height exceeding 2,5 meters above the bottom
   edge of the burner.

Swedish   F4A F/R
European   EN 50266-2-1
IEC-   IEC60332-3-21
   Cables are mounted on both sides (front and rear) of the ladder.
   The total number of test pieces shall provide a nominal total
   volume of non-metallic material of 7 liters per meter. The test
   flame shall be applied for 40 minutes.

Swedish   F4A
European   EN 50266-2-2
IEC-   IEC 60332-3-22

   Cables are mounted on the front of the ladder. The total
   number of test pieces shall provide a nominal total volume of
   non-metallic material of 7 liters per meter. The test flame shall
   be applied for 40 minutes.

Swedish   F4B
European   EN 50266-2-3
IEC-   IEC 60332-3-23
   Cables are mounted on the front of the ladder. The total
   number of test pieces shall provide a nominal total volume of
   non-metallic material of 3,5 liters per meter. The test flame shall
   be applied for 40 minutes.

Swedish   F4C
European   EN 50266-2-4
IEC-   IEC 60332-3-24
   Cables are mounted on the front of the ladder. The total
   number of test pieces shall provide a nominal total volume of
   non-metallic material of 1,5 liters per meter. The test flame shall
   be applied for 20 minutes.

Swedish   F4D
European   EN 50266-2-5
IEC-   IEC 60332-3-25
   Cables are mounted on the front of the ladder. The total
   number of test pieces shall provide a nominal total volume of
   non-metallic material of 0,5 liters per meter. The test flame
   shall be applied for 20 minutes.


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