When equipment fails

I am new to NACHI and studying for my certification. Here is a scenario that I need guidance in.

An inspector is with the client during the inspection of a newly constructed house. The inspector uses a tester to check the Arc Fault interrupter. Using the tester, it shows that the Arc Fault fails to trip in several rooms. The finding in the report is noted as such. The builder insists there is no problem with the wiring. It is an evolving situation and not resolved yet, but I have come to learn that this particular tester is discontinued due to failure to properly test.

If a testing device indicates a failed system, do you have a backup to confirm the accuracy of it, what is it and what is the liability of the inspector?

When in doubt use the test button on the device. That is the approved method of testing. You could trip the device with the test button and then go to the various locations to confirm that power has been removed where it should be, then reset the device and again confirm that power has been restored.

Yes… and also always have spare batteries , camera shoes and socks pants and shirt water soap and towel , Flash lights too.

Always use the test button and procedure supplied by the manufacturer of the listed device, not a third party tester or unsupported protocol.

I think some have missed the real question:

Yes, you need a back-up method to confirm or validate your findings, no matter what type of system you are testing. It could another tester or device (same brand, different brand, older version, newer version, etc.)

If the system you’re testing has an established testing protocol or Standard, then use it.

As to liability, once you report a finding you had better be sure of it’s accuracy, no matter what method you used to arrive at the conclusion.


As stated above, the AFCI test button on the unit itself is the only approved testing device approved by the units manufacturer. What is the brand/type of AFCI tester in question? Plug-in AFCI testers are not yet common. A GFCI tester DOES NOT test for AFCI. We need the facts for any qualified reply.

There is no backup to the manufactur’s on board tester for an installed AFCI device. It works or it doesnt. It passes that test or it fails.

In general, I have back up of almost everything.

Tools can and will fail in the middle of an inspection. And yes, sometimes I grab a back up device to get a 2nd opinion.

Ian, Specifically, how do you test AFCI devices? And Backup? Thx.

That’s fantastic, however, I think he was using that as an example. There are plenty of other devices or testers we all use for many systems, not including AFCI breakers.

That’s all good and well, but the OP specifically used the AFCI scenario, therefore my reply was directed to that device.


Come on Joans, put on your reading glasses and follow the thread.

As Dominic correctly pointed out "he was using that as an example. There are plenty of other devices or testers we all use "

This isn’t about AFCI, it’s about having back up plans.

Which is why I said, very clearly

"In general, I have back up of almost everything. "

Keywords being “in general” (i.e. general inspection equipment, not limited to AFCI) and “almost” (meaning, no, I don’t have a back up of every last tester).

But since I do pay you in imaginary cookies to give me a hard time, I’ll answer your question, even though it has NOTHING to do with my response:

Up unit 6 months ago, Los Angeles County only required AFCI if the receptacle was brand new, and specifically exempted all panel upgrades from having to follow the NEC recommendation on AFCIs.

As of 6 months ago, Los Angeles County dramatically altered their language but specifically still exempted all panel upgrades if the new panel is within 6 feet of the old panel (why 6ft? I don’t know, do arc faults care about length? I doubt it).

Given 98% of the homes I inspect were built between 20 to 100 years ago, I rarely ever see AFCI breakers installed.

And the few times I do actually see these almost near-mythical breakers, I test them at the breaker at the panel by pushing the test button with my finger. Thankfully, I have 10 fingers, so I have 9 back up fingers should one finger become unusable during an inspection. :stuck_out_tongue:

Having a backup is good practice and I recommend it. It’s happened to me before.

Wow! Bad day?

As you know, I am not green behind the ears, and I actually respect your opinion on many topics. I simply was curious what methods you employ for testing AFCI’s. Just because it is me asking, does not mean you should automatically get defensive thinking I have an ulterior motive.

<<Well, maybe just a little.>> Ha-ha-ha! :wink:

Several test meters today have the capability of testing GFCI’s & AFCI’s.

Most of these cost in the mid $200 to mid $300 range.

Although I’ve heard inspectors say the AFCI did not trip with this OR that meter, its never happened to me. If it did I’d still report it.

I’ve had GFCI’s trip by their trip button BUT not with a meter … I report it, cause being old, I don’t think if I was getting shocked I would have the presence of mind to say “Oh golly, I’m getting shocked I better reach over there and push that little trip button”.

I don’t carry a back up inspector with me, but sometimes I still end up with a 2nd opinion. :exploding_head: