There may be a Canadian equivalent to NFPA standard 780-2000 that is used below the 49th parallel. It is not ‘breezy’ reading, but carries a lot of weight. Using such a document as the basis for review of an existing installation “do’s and don’ts” may be worthwhile.
Periodic ground-resistance “fall of potential’ {3-lead} testing is also fairly common in lightning-protection maintenace. With the lightning-protection ground rods forming a grid of larger area, {than, say, a single rod} recommended spacing for test electrodes may be quite large
http://www.aemc.com/techinfo/techworkbooks/ground_resistance_testers/950-WKBK-GROUND.pdf [40 pages ~360KB]
http://205.247.219.223/training/catalog/common_viewproduct.asp?product=122 [description only]
The effort and expense generally expended for maintenance of a lightning-protection system has a lot to do with the value of the protected facility. A 17th-century museum or television studio usually gets a lot more attention than a convenience store or hay barn.
