Where do I learn about timelines of code changes?

Is there any resource on the history of certain code additions or revisions? For example, when was AFCI first introduced into code and in what areas, and when were the required areas revised?

For questions such as that, I just ask ol’ GooGoo… Maybe others will have a good reference site they can post.

Yeah, Google is your best bet for specific items. As for AFCI, I believe it was first introduced early/mid 2000s. There were lots of exceptions and variations though. My state of Oregon only adopted it in bedrooms for a few years until finally requiring it in all the NEC places later. To this day there are exceptions for things like swapping panels in older houses (it’s not required). Pre-AFCI houses were not wired with the intent of AFCI protection and introducing it retroactively can cause a lot of nuisance tripping. For years vacuum cleaners caused a lot of nuisance tripping. I haven’t heard much lately so they must have got that figured out.

Can’t remember where I found these…


GOOD INFORMATION Ryan. I had these about 3 or 4 years ago, and lost them when I printed them out from my computer.

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wow thanks Ryan!

if anyone knows of similar resources id love to see them. I was actually specifically curious about gfci & afci but im sure there are other things I get asked about all the time by clients and realtors

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Here’s a chart from Jerry Peck - He’s an overflowing brain in the world of inspections. A bit of a know-it-all if you’ve run across him on message boards but a ton of knowledge that he’s willing to share freely if you can hang in there long enough.



Keep in mind the majority of building codes were written to ensure the health and safety of the occupants. Home inspectors can only point out health and safety reasons why complying with modern building codes are beneficial. Only licensed state, county and city building code inspectors enforce code. A home inspector can’t say a missing GFCI in a bathroom is a safety violation, Instead recommend adding a GFCI to help prevent electrical shock. IMO Every inspector should take the time to read and understand the safety and health reasons for building codes.

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Here is a good article about the different code organizations and how the ICC was formed. While it doesn’t go into the specifics of individual codes it does lay out the history of code groups. From there it easier to understand where individual codes originated.

Evolution of Codes.pdf (92.2 KB)

As to your AFCI question, it first appears in the 2002 NEC as a single reference.

440.65 Leakage Current Detection and Interruption
(LCDI) and Arc Fault Circuit Interrupter (AFeI).
Single-phase cord-and-plug-connected room air conditioners
shall be provided with factory-installed LCDI or AFCI
protection. The LCDI or AFCI protection shall be an integral
part of the attachment plug or be located in the power
supply cord within 300 mm (12 in.) of the attachment plug.

In the 2005 NEC it has its own article:

210.12 Arc-Fault Circuit-Interrupter Protection.

The rest is history!

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