Low voltage
The electric code makes a distinction between "high" voltages above 100 volts, and "low" voltages below that. For circuits defined as low voltage, in some jurisdictions, there is no requirement for licensing, training, or certification of installers, and no inspection of completed work is required, for either residential or commercial work. Low voltage cabling run in the walls and ceilings of commercial buildings is also typically excluded from the requirements to be installed in protective conduit.