210.25. Branch ckts in buildings with more than one occupancy.

210.25(B)- common area branch ckts.
Ma. has an exception:210.25(B)-

"Exception:Branch ckts supplying lighting outlets in common areas on the same floor as a dwelling unit in a new or existing two-family or an existing three-family building shall be permitted to be supplied from equipment that supplies one or more of those dwelling units."

My question: Existing two-family.
If I install interconnected smokes & CO det. (required in Ma.) for both units and common areas (2-family)and the common area lights (same ckt),Off of a tenants panel.
Side by side units 2 floors each. Existing house.(used to be owner occupied).

Would this be accepted?