Don - I thought I'd throw this at you since you are a wealth of information about the minute details of the code.
In the Mike Holt forum it was stated: "Also bonding is required around reducing washers if the metal raceway is used as an EGC per 250.118".......which led to "Reducing washers to not allow the low impedance path as required in 250.4(A)(3)."
My question: Where is the documentation, code recital, UL or other Standard that supports such a claim?
I have read in Mike Holt's 'Ground & Bonding' and in Soares ' Book on Grounding' that "reducing washers are not suitable for bonding and should always be bonded around"
HOWEVER - neither of these books cite or footnote a study, report, document, or standard that reducing washers do not meet a 'low impedance' criteria.
The reason I bring this up is that both of these books usually refer to studies, standards or the code, etc. in supporting such a statement......AND - how would an inspector be able to support such a requirement to the electrician in the field with 'Soares says so in his book'.?
I know some devices/materials are not tested by UL and as such automatically do not satisfy a standard - but I don't know where to look further to satisfy this curiosity I have around this reducing washer issue.
Thank you for any information you may be able to provide on this subject.
