The real issue is the guy who drops a packaged spa on an existing concrete patio slab (no supplemental decking).
The AHJs were requiring that they install a raised deck, nonconductive material, around the spa, out 3'. This was typically Trex or another plastic. This was to avoid tearing up the slab and putting in bonding. The spa stores have them as an accessory but I am guess the spa people thought, in tough times, it was hindering sales.
