680.26(B)(2)(a) now requires Conductive paved portions of perimeter surfaces, including pavers, to contain an equipotential bonding grid to protect from stray and contact voltage. The provision for a Single Wire has been REMOVED. The single wire can be used in areas that are not paved pedestrian walkways, such as infinity edges and rock waterfalls, etc. But it can only be used to connect sections of the grid that are installed in pedestrian walkways.
The Three Acceptable Methods
1. Use minimum #3 rebar tied in a 12” x 12” grid, chaired to be fully embedded in the paving.
2. Use minimum ASTM 6×6-W2.0 x W2.0 welded wire sheet, chaired to be fully embedded in the paving.
3. Use minimum # 8 solid bare copper wire grid, welded in a 12” x 12” grid. Embedding not required, can be installed on or in the earth or paving.
Whichever grid is chosen, it must be connected to the pool shell at four (4) places spaced uniformly apart if the shell is conductive, such as gunite/rebar or steel wall for vinyl liner. The grid must be placed no more than 6” below finished surface, and cover the first 3’ from the inside edge of the pool.
Option 3 – CMI’s Equibond
CMI’s EquiBond™, equipotential bonding grids are constructed from #8 AWG 99.99% pure solid copper bare wire, welded in 12” x 12” spacing, and are 3’ wide. Stock lengths are 100’, 125’, and 150’ long, but custom lengths are always possible. Each Grid also contains engineered drawings and product information, 16 metal stakes, and 20 pcs. of #8 Direct Burial Split bolt. The quantity of 20 is developed from 4 corners with 4 connections at each corner, and 4 more for connecting the bond wire to the shell spaced equal distance apart. Everything needed to be installed by one person.
CMI’s copper EquiBond™ grid does not need to be chaired and embedded in the paving, it can be installed in the paving or the earth, or on top of the earth. This is especially useful with paver decks, as the copper grid can be place right at the top of the fine sand and the pavers installed directly onto it and the sand as usual. Because it is constructed from pure copper, it will not rust or erode, and over great lengths of time, will provide proper protection against stray and contact voltage.
CMI’s staff includes members of the NFPA and IAEI. We attend national, section, chapter, and department meetings, are always willing to answer questions and provide training.