T 2.12 Insufficient documentation on cabling

If the exact locations of some cables are not known because the documentation is inadequate, these cables could be damaged during construction work inside or outside the building. It cannot be assumed that all cables and lines in the installation zones were installed according to DIN 18015-3 "Electrical installations in residential buildings - Part 3: Wiring and disposition of electrical equipment", or similar standards. In particular, when cable conduits are built or cables are laid during the concrete construction phase, cables may change position while the concrete is being poured due to changes in the surrounding system. Chaotic cabling is often found in gypsum board stud constructions. When cables and lines are installed in floors or ceilings, geometric or direct cable routing can be selected. Random cable routes are also possible, in which case it may be impossible to determine where cables are routed in the floors and ceilings based on the location of the electrical equipment (lamps, switches, tanks, etc.). Failure due to damaged cables can result in prolonged downtimes, or under some circumstances even in life-threatening hazards, e.g. due to electric shock.

Insufficient documentation can also make it more difficult to test, service, and repair cables.