The IBC Section 302.1.1 covers incidental Use Areas. The only electrical only type incidental use requiring a fire rated barrier wall and floor/ceiling assemblies is for stationary lead-acid battery rooms having a liquid capacity of more than 100 gallons used for facility standby power, emergency power or interrupted power supplies.
These rooms require a 1 hour rating for Group B, F, H, M, S and U occupancies and a 2 hours rating for Group A, E, I and R occupancies.
Other common incidental use areas would be: furnace rooms, boiler rooms, refrigerant rooms, parking garages, incinerator rooms, paint shops, laboratories and vocational shops, also laundry rooms, waste and linen collection rooms and storage rooms over 100 square feet, and padded cells.
