Residential electricians have their own state license that allows them to perform electrical work in residential settings. Just as the name suggests, that generally means working on houses. Sometimes this also extends to apartment complexes and condos, but often these are considered to be commercial buildings, and thus different licenses are required.
Commercial electricians have what’s called a “general” electricians license. This allows them to perform electrical work in all types of settings, typically commercial and industrial. Commercial work is work on any commercial building or setting, which includes anything from fast food joints to hospitals, research facilities to amazon warehouses.
Industrial electricians also hold a general electricians license, they just work in industrial settings. Industrial settings are different in a number of ways; they often involve PLC’s, or programmable logic controllers, start-stop buttons, conveyor belts, heavier equipment.
Commercial and general electricians, or anyone with a general electricians license, can do residential work. Those with residential licenses can ONLY do residential work.