Part 5-56 contains general requirements for safety systems, the selection and installation of electrical supply systems, and power sources for safety systems. The requirements apply to supply circuits and power sources for electrical equipment used in safety systems.
Published Amendment A1 introduces clarifications regarding the installation of fire-resistant cables by easing fastening requirements on horizontal cable ladder sections. The amendment clarifies the interpretation that the primary objective is to ensure that cables remain on the cable route. At the same time, it emphasizes a comprehensive approach to the operational reliability of safety systems, including during fire situations.
SFS 6000-5-56:2022/A1:2026 – Low-voltage electrical installations. Part 5-56: Selection and erection of electrical equipment. Safety services / Amendment
Previously, the fastening requirement for cables specified a maximum fixing interval of 1.5 metres also for horizontal sections. This was re-evaluated by SESKO committee SK64. The review was based on the interpretation that, on horizontal cable ladder sections, the key objective is to ensure that the cables remain on the cable route rather than being tightly mechanically fastened along their entire length. As a result, it may henceforth be considered that, for example, bridge-type supports provide a sufficient means of ensuring that fire-resistant cables remain on the cable ladder in accordance with the intent of the standard.
Less rigid fastening makes it possible for the cable to remain in place or retain its functionality for a longer period even if the cable ladder fails. Excessively dense and rigid fastening does not necessarily improve overall safety. The review also took into account the structural effects of fire situations:
- if the cable ladder collapses, tightly fastened cables may collapse with it
- more lightly supported cables may therefore better retain their functionality
The published standard may be applied immediately, and it can be purchased here:
SFS Suomen Standardit – SFS 6000-5-56:2022/A1:2026
Further information on low-voltage electrical installation standards is available from Olli Hakulinen at SESKO ry.
Participation in standardization activities: Joining SESKO standardization work
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