Component density is the level of compactness or concentration of components on a printed circuit board. It is a measure of how closely the components are placed together on the board. Several factors influence the component density on a PCB, including the component pitch, the size and number of regulator circuits, the presence of large non-electrical hardware, component keep-out restrictions, space requirements for sensors and antennas, the nature of the board and its intended function, the IPC class indicating the level of reliability required, and any assembly process considerations.