In article ,
Doug Miller wrote:

[ sneck ]

... That's not unheard of, you
know: the Chicago electrical code, as I understand it, is *based* on the
NEC,

Chicago Electrical code bears only a vague resemblance to the NEC. Most
jurisdictions cite a particular year of the NEC (or of the BOMA -- Building
Owners and Managers Association -- code, which incorporates by reference
the NFPA -- National Fire Prevention Association -- code, which incorporates
the NEC by reference) as 'base', and then add any additional jurisdiction-
specific rules.

The Chicago building code specifications for electric wiring does *NOT*
do that. Everything is specified directly in the local code. And the
code itself is a 'swamp'. I once had a 'difference of opinion' with
a building inspector over an electrical issue, and we spent a good
five minutes citing code 'exceptions' back and forth at each other.
Chicago code does -not- say 'this section rules _unless_ the exception
in xyz applies', it says "if this condition is met, then section xyx does
not apply". Chasing the applicable exceptions to a given section is a
challenge. And the section that contains an exception to the base-line
rule, may itself be subject to an 'exception' in a far-removed section
of the code. "lather, rinse, repeat" applies.

I eventually prevailed over the electrical inspector, having reverse-
engineered the code one step further than the inspector had. And he
'went away unhappy', having _not_ collected a payoff over the purported
'code violation'.

Chicago electrical code allows some things that are forbidden by NEC,
and forbids other things that are allowed by the NEC. There is a fair
amount of 'coincidental' overlap on the basics, but a *lot* of difference
in the 'details'.