Lights that flicker and dim periodically are very common. However, they can also be a sign of something more dangerous.  If you begin to notice a slight flicker or a brief dimming, this indicates that there is a poor connection in your electrical system, and arcing electricity is most likely the cause. An arc fault occurs when there is a loose connection in the wiring.  The electricity will jump through the gap in the loose connection to complete the circuit. This arcing causes a great deal of heat, and here's the danger:  arcing - especially over time - causes the wires to deteriorate, resulting in a serious fire hazard. Call McNatt Electric immediately if you are experiencing any of these issues.