The fire index indicates how easily a material can ignite, how much smoke it produces, and how significantly it contributes to the spread of fire.This is determined through tests and plays a crucial role in building safety.

The fire index 5.3 defines the fire properties of building materials.  

The first number, "5," indicates that the component is flame-retardant.
The second number, "3," provides information about the smoke development of the material, with 3 as the highest value indicating weak smoke production.  

This classification is crucial for assessing the safety and suitability of materials in fire protection-relevant areas. 
It is noteworthy that plica's Longlife components are unique in the Swiss market, as they meet the strict requirements of the fire index 5.3 of the VKF (Association of Cantonal Fire Insurers) and stringent legal regulations.

The NIN 7.12.5.2.1.2 standard outlines the requirements for safe electrical installations. Choosing the right products is crucial to comply with legal regulations and ensure safety.

Important points: 

• Only materials with an appropriate fire index may be used. 
• Materials that are highly flammable and produce heavy smoke are prohibited in certain areas!

The PV direct current main line must be installed in a fixed location, and insulation materials that meet increased insulation requirements (halogen-free insulation materials) must be used. PVC insulation is not suitable for this purpose.
If the possible short-circuit current does not or only insignificantly exceeds the operating current, no further measures are required for short-circuit protection.

If such cables pass over combustible building parts (surface mounted) or are installed in combustible building parts (flush mounted), they must be installed in low-flammability (RF2/BKZ 5.2) or non-flammable (RF1/BKZ 6q, BKZ 6) pipes or ducts, or cables with a metallic sheath or a concentric conductor must be used (no PVC insulation)