A critical assessment of the US code for lightning protection of boats

It is argued that the US code for lightning protection of boats is seriously inadequate. Downconductor conductance should be specified as that of #4 gauge copper rather than the #8 gauge presently specified in order to minimize the risk of overheating and melting. The 1-ft² ground plate is shown to be inadequate to prevent side flashes in fresh water. The magnitude of the potential gradients involved is 2 orders of magnitude larger than the breakdown value if the effect of breakdown in the water is ignored. In salt water, a 1-ft² ground plate is adequate. The concept of a cone of protection with a 90° apex angle is not applicable to the attractive effect of sailboat masts because it underestimates the probability of strike occurrence by an order of magnitude