The first thing to know is what these things are actually called so it helps to remember the difference. GFCI stands for ground fault circuit interrupter and AFCI is arc fault circuit interrupter. These two things will almost look identical but do completely different things. This article is not going to describe exactly what is going on with these devices but to explain it in a way that you will understand what it is for, which is the important part.
GFCI
This device is made to protect you from being severely electrocuted. The GFCI is constantly measuring the electricity going in and out of the device. If you were being electrocuted, some of that electricity is going through your body and would imbalance the measurement in the device. When the GFCI notices a drop in electricity, it will automatically shut off power so you are not continually being shocked.
A GFCI can come in the form of a receptacle or breaker but both devices will still do the same function. A GFCI receptacle can usually be found on the exterior of the home or areas near a pool of water like a sink or a bathtub. In 2014, there was a new electrical code established that essentially 95% of the receptacles in your home need to be protected by a GFCI/AFCI breaker. You do not have to convert your breakers if your home is older than 2014 but if you want to make your home 100% safe, these protectors would be a great addition to your home.
AFCI
This device is made to protect your home/office from an electrical fire. This type of protection is commonly seen in the breaker form but there are receptacles with the same function. Your normal breakers will trip if the live wire touches metal that is grounded or it touches the neutral (these are not the correct terms but is usually referred this way), an AFCI device will do this and sense if there are minor sparks in the circuit. The minor sparks can be a result of a nightstand pinching an electrical cord or a nail that is holding a picture nicks a conductor in the wall to name a few examples. When the AFCI device senses a minor spark, it will shut off power so that it will not continue to feed the possible electrical fire. These devices were starting to be used in the late 90s but before 2014 were only needed for bedroom receptacles. Now this device is needed for all receptacles except for kitchen counter receptacles and appliances.
Summary
The easiest way to remember the difference is a GFCI protects your health and an AFCI protects your property from an electrical fire. I hope this helps you understand your home or what you need in your home a little more. For more information, or questions or concerns, please contact us.