Fire barrier (cable)

from Wikipedia, the free encyclopedia

Fire sealing is a part of structural fire protection (sealing principle). For this purpose, buildings are divided into fire compartments and sealed off from one another, depending on the building class and the use of the building .

In order to offer protection in the event of damage in accordance with the general requirements of the building regulations and to avoid any danger to life or property, it is necessary to prevent a fire from spreading for so long that the building can be evacuated and the fire brigade can effectively fight the fire is. The fire compartments are demarcated or sealed off by walls and ceilings with a certain fire resistance (typical classes are e.g. 30 or 90 minutes). In order to maintain the fire resistance, these fire compartment-forming walls and ceilings must not be interrupted. However, since buildings are always criss-crossed with different installations, it is necessary to create openings for them. In order to restore the fire resistance of the fire compartments at these penetrations, installers must take appropriate compensation measures in the form of approved fire barriers, ventilation flaps, fire barriers , etc. If different installations (cables and pipes) are routed through common openings and sealed with a partitioning system, we speak of combination partitioning.

Cable insulation

In the electrical installation, so-called cable bulkheads or cable bulkheads are used for fire protection, which must be tested and approved according to DIN 4102-9 or DIN EN 1366-3 or for which a European technical assessment has been issued according to the new construction product regulation. If these systems are installed properly (in accordance with their approvals), they prevent the spread of fire and the transmission of smoke for at least the specified fire resistance period. The fire resistance duration of cable penetrations and combination penetrations, which are tested according to DIN 4102-9, is z. B. indicated with S90. The S stands for bulkhead and the 90 for 90 minutes fire resistance. The sealings tested according to the European harmonized standard EN 1366-3 are z. B. classified with EI90. The E stands for the room closure (French: Étanchéité) and the I for the thermal insulation (insulation). In contrast to the classification according to the German standard, a system according to EN could also be identified as E90 I60. The applicability of these EN-tested systems is based on the respective national fire protection requirements.

Admission requirements

Since the processing of these systems is not regulated separately, i.e. not necessarily assigned to a specific trade, basically anyone who adheres to the installation regulations regulated in the approvals can install cable insulation.

This is different with so-called combination bulkhead systems. Due to the complexity of the regulations in the approvals, the national approval body, the German Institute for Building Technology (DIBt) , has made it mandatory that the fitters must be trained by the respective system manufacturers or approval holders. Fitters trained and certified in this way are listed by name at DIBt and are then allowed to process the respective bulkhead systems.

The installation regulations in the approvals are always positively formulated, i.e. H. only that which is explicitly described in the approval may be done. The respective installer must then declare to the client with a confirmation of conformity that he has carried out everything in accordance with the relevant approval. He is then responsible for the functioning of the bulkhead system and can also be called to account in an emergency.

Cable insulation systems

For the isolation of cables, a large number of different isolation systems have been developed over the past 30 years, all of which offer advantages and disadvantages for the respective application. Important points here are the fire resistance and the type of wall or ceiling as well as their thickness. In the case of lightweight partition walls, for example, soffits may have to be built into the openings. If the wall thickness is too small, it is possible that, for. B. additional planking must be provided.

Fiber optic cables are also usually covered by the approvals. However, glass fiber bundle tube systems (blown fiber tubes) must be viewed separately from this. These are not covered by standard approvals according to DIN 4102-9 and require a separate test and approval.

Another important principle is that bulkhead systems must not be mixed with one another.

Mineral fiber bulkhead

Mineral fiber bulkheads are cable bulkheads made from high density mineral fiber boards with additional coatings. The panels are placed in the openings, the installations are worked on and then coated. There are coatings that foam up in the event of a fire and form an insulating layer, and so-called ablation coatings that absorb heat in the event of a fire through endothermic processes in the material and "isolate" it in this way. The cables and cable routes that are passed through must also be provided with this coating on both sides of the bulkhead in different lengths (e.g. 15 cm) and in a certain thickness.

Mortar bulkhead

Mortar bulkheads prevent fire from spreading through wall and ceiling openings. Also referred to as "hard bulkhead", this system closes penetrations from space-enclosing components, e.g. B. with pipes or cables fire-resistant and smoke-tight. The mortar is introduced into the perforations in a certain minimum thickness (generally 15–20 cm). A mortar or hard bulkhead consists of fire protection mortar which is mixed with water before processing and then introduced into the component opening. In accordance with the existing building inspectorate approvals / test certificates from the individual manufacturers, minimum clearances must be observed between the media lines and the component reveals. The maximum specified cable cross-sections must also be taken into account. The bulkhead size is described in the respective approval. Here, however, the 60% rule can largely be assumed. This rule states that a partition may be covered by a maximum of 60% of the pipeline systems and that at least 40% fire protection material must be present.

Fire protection cushions

Fire protection cushions, also called “cushion bulkheads”, are elements for sealing off cable openings. They consist of a filler material based on mineral fibers and foaming building materials and are z. B. enveloped by fiberglass fabric. For installation, the cushions are placed horizontally, in layers and mutually offset in the opening. Cushions of different sizes help that the joints between cable support structures and opening reveals as well as the gussets between cables are sealed over the entire thickness of the bulkhead and that all cables are tightly encased. To prevent unauthorized persons from removing the fire protection cushions, they are partially protected with wire mesh.

Fire protection foams

Fire protection foams are usually filled into cartridges and consist of several components that are mixed when pressed out, foam in the opening, react completely and then harden. In the event of a fire, they foam up through heat and a. as cable insulation.

Stoppers and shaped blocks

The shaped blocks are stacked in the opening in the manner of bricks and the respective installations are worked on. Remaining openings are closed with system-related cartridge foam or fire protection putty. For core drilling there are suitable plugs, depending on the diameter, which are integrated into the opening on both sides; Remaining openings or gussets are closed with appropriate putty. The plugs and shaped blocks also foam up in the event of a fire and form an insulating layer that prevents the fire from spreading.

Cable boxes

Cable boxes are prefabricated seals. They consist of a sheet steel housing that is installed in openings in walls, floors, ceilings and in the underfloor to guide cables through and seal them off against fire and smoke. The box is lined with fire protection packages that foam up in the event of fire and seal the interior. After the cables have been passed through, the box is sealed against smoke at the front with special foam plugs and a permanently elastic sealant.

Sand traps

Sand traps, also known as sand cups or sandboxes, are used to feed cables through walls. A box made of sheet steel is attached to the wall on both sides, the upper edges of which are higher than the upper edge of the hole to be sealed off. The cables are fed through the wall and fixed in the trap with retaining lugs. Then the cable entry is filled with sand with a grain size of 0–2 mm. The advantage of this solution is that it is relatively easy to add additional cables later without destroying the sand trap.

See also

literature

  • Dietmar Hosser: Fire protection in Europe - dimensioning according to Eurocodes: Explanations and applications for the fire protection parts of Eurocodes 1 to 5. Beuth-Verlag (2012) ISBN 3410167668

Web links

Individual evidence

  1. ↑ Regulation (EU) No. 305/2011 (PDF) laying down harmonized conditions for the marketing of construction products and repealing Directive 89/106 / EEC, Article 2 point 13