Please read a new article written by the leading Russian specialist in grounding and lightning protection, E.I. Bazelyan. This article is intended to provide the most common mistakes and errors made by the specialists designing lightning protection systems.
The considered technical solutions have been classified into three major groups: lightning rods, current collectors, and grounding devices. For each group the author details the errors associated with the solutions as well as the requirements of regulatory documents. Sometimes, clearly absurd things appear. For instance, the use of a lightning protection grid for a metal or reinforced concrete roof. Or a ridiculous point about insulated current collectors aimed to reduce electromagnetic interference to the electronic equipment.
And surely we will also consider in details the conventional example with the earthing resistance value for the lightning rod. We are talking about documents SO-22.214.171.124-2003 and RD 34.21.122-87, where, for some unknown reasons, only the lightning rod structure is rated rather than the grounding resistance. The author convincingly shows what danger is entailed for human health by the lightning rod's grounding electrode made without consideration of soil resistivity where this electrode is installed.
Other examples of what you "should not do" can be found in the article Worst Lightning Protection Ever.