Chapter 40 is titled 'Devices and Luminaires' and covers the requirements for the use of elements of an electrical system which provide safe means for end users to connect and disconnect a circuit and provide illumination. The purpose of this chapter is to prevent explosions, fires, electrical shocks and burns, electrocution, and/or premature degradation of materials.
The model shows a receptacle which allows an end user of the electrical system to safely connect appliances, equipment, and/or lighting fixtures; and a light bulb (defined as a 'lamp' in the code), which gets installed into a luminaire.