Safety devices in homes have come in many forms over years, some of which are relatively inexpensive and require only small modifications to existing hardware to put in place. However, these changes can have a significant impact on the safety and well-being of a home’s occupants and create a safer environment to call home.
One type of safety device which has become more widespread in recent years is the Arc Fault Circuit Interrupter (AFCI). While GFCI’s (Ground Fault Circuit Interrupter) serve to prevent shock or electrocution due to a ground fault, AFCI’s protect occupants from an arc fault, which can result in an electrical fire. While GFCI’s have been around since 1965, AFCI’s first came onto the scene in the 1980’s.
An AFCI is an advanced detection system that turns off a circuit when an unsafe electrical arc is detected. AFCI’s can tell the difference between a normal arc (such as a vacuum or furnace motor turning on or off) and an abnormal and dangerous arc. While arcing can be intentional (such as with an arc welder) arc faults are an unintended arc flowing through an unplanned path. These can reach extreme temperatures that exceed 10,000 degrees Fahrenheit, a temperature similar to the surface of the sun. This can quickly ignite wood and insulation near the arc fault, which are common items inside a home near electrical wiring.
A significant part of what an AFCI does is detecting the difference between normal and abnormal arcs. Normal arcs are typically periodic or repetitive and can be non-sinusoidal, while abnormal arcs are non-periodic or non-repetitive waveforms. When an abnormal arc is detected, the circuitry inside the AFCI trips the internal contacts, which de-energizes the circuit and helps to prevent an electrical fire. The time between an arc fault being detected and the AFCI breaking the circuit can be less than one-tenth of a second. Like a GFCI, this extremely fast breaking of the circuit can prevent dangerous conditions from forming inside the electrical system.
In recent years, AFCI’s have become standard in almost every living area of a home such as bedrooms, living rooms, kitchens, and other areas. Like GFCI’s, Arc Fault Circuit Interrupters work constantly and silently to protect occupants from the hazards surrounding arc faults and the fires they can cause. With over 40,000 fires being attributed to electrical sources every year, resulting in more than 1,400 injuries and 300 deaths, AFCI’s are a critical electrical safety device to have in place in homes both new and old.