f) Membrane Penetrations. Walls may have openings for steel electrical outlet boxes not exceeding 16 square inches in area ,provided the aggregate area of such openings is not more than 100 square inches for any 100 square feet of wall or partition area . Outlet boxes on opposite sides of walls and partitions shall be separated by a horizontal distance of at least 24 inches . Where wall-protective membranes are penetrated by other materials or where larger openings are required than permitted above, the penetrating items shall be:
1. Protected with membrane-penetration fire stops suitable for the methods of penetration.
2. Installed in accordance with the installation instructions of their listing for such use.
EXCEPTION:Penetrations not larger than a 4-inch nominal pipe or 16 square inches in overall cross-sectional area containing noncombustible penetrating items, where the annular space between the penetrating items and the protective membrane being penetrated is filled with a material which will prevent the passage of flame and hot gases sufficient to ignite cotton waste when subjected to U.B.C. Standard No.43-1.Time-temperature fir conditions under a minimum positive pressure differential of 0.01-inc water column at the location of the penetration for the time per
Checking with the AHJ is the best answer because there could be other factors involved like.. is that an acceptable location for the panel.
If it is going in the wall a generally accepted way of maintaining the raiting is a drywall box out. Maintaining required air space between layers. Being a house and probably a 3-1/2" studwall, with a box out it will end up a semi-recessed panel.