bubble covers are now the rage in the 02', you can read the if, buts & ands in 406.8 (a) (b)

there is not a handbook commentary on this, which is a pity because i suspect the history ties in with the recent UL uprade of GFI's to 'lockout' status.

IMO, GFI's are a sensitive device, easily abused by New England weather here, so i simply wire from the load side of the panel GFI on out to these.

Rumor has it that GFI listings allude to a bubble cover, maybe someone here can quide me into the correct white book section?