Question

during the construction a of a building the lightning conductor was left hanging in the air by mistake. Would the lightning conductor still be effective? Explain.

Answer 1

They may only be used in new construction.  You cannot use building steel as your ground terminal (electrode) when installing a lighting protection system on an existing building.  NFPA 780 4.13.3The concrete encased electrode must be installed near the bottom concrete foundation or footing of the building.  This means that it must be a spate electrode and cannot be the foundation itself.  NFPA 780 4.13.3.1The concrete encased electrode must be indirect contact with the earth and be at least 20-ft (linear) in length.  There are additional rules as to the copper vs. steel content of the electrode.  NFPA 780 4.13.3.1 & 4.13.3.2

Answer 2

during the construction is a lighting condecter was left hanging in the air by mistake