A. I think the code is specific enough to make it clear when violations are present. I would ask the local inspector to clarify any concerns or gray areas. Meeting the requirements as set forth by code and inspectors is the only sure way to cover yourself, and liability is a real concern when doing electrical work. I am not aware of any specific National Electrical Code references to old work correction requirements. The local rule for remodeling a residence is that if 50% or more of a building is being affected, then the entire building must be brought up to code.
If you don’t know exactly what you’re looking at and how it should look, call someone who does. This stuff (electricity) is responsible for deaths every year that can be avoided.
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