Bare steel conductors, embedded in concrete

• Structural reinforcement steels must not be used as earthing conductors.
• Statically required components must not be used as earthing conductors.
• Welding earthing parts to the structural reinforcement is not permitted.

When laid in concrete

• Parts of the earth-termination system must be checked before concreting.
  This is done by an approved inspector or qualified electrician.
  This partial acceptance must be documented.
• For series-produced precast concrete parts, the check is carried out during technical acceptance.
• In case of individual concrete production, the check is carried out directly at the manufacturer's premises before concreting.

Concrete-embedded joints 

• Concrete-embedded joints must generally be welded to be short-circuit-current-proof. The defined welding seam lengths and thicknesses must be observed:
  
  Welding seam length
  In case of short-circuit currents ≤ 25 kA at the installation point, a length of at least 2 x 30 mm is required - in case of short-circuit currents > 25 kA, a length of at least 2 x 45 mm is required.
  
  Welding seam thickness
  To avoid a reduction in cross-section, an effective welding seam thickness of 4 mm is required.