Outlets—the common term for electrical receptacles: You can’t enter a modern building without seeing them, and they all seem pretty much the same, right? Wrong! As electrical construction practices have evolved over the years, electrical outlets have evolved along with them, building in greater safety features.
The old-school, two-pronged receptacle that you remember from your grandma’s house was installed in residences before 1962 and is no longer recommended for any structure. Since 1971, the National Electrical Code has required at least the standard three-pronged, grounded receptacle, which reduces the risk of electrical shock and protects equipment from damage. From there, receptacle design has advanced to cover a range of safety needs.
TRRs: Tamper-resistant receptacles are recommended for homes with children or pets, as outlet covers have been proven not to provide adequate protection. In a TRR, a built-in shutter system prevents objects from being inserted, except when simultaneous, equal pressure to both slots is applied by a plug.
AFCIs: An arc-fault circuit interrupter reduces the risk of fire by interrupting power when an arc fault occurs anywhere in the circuit, including within the items plugged into it—even attached cords. The Consumer Product Safety Commission estimates that more than 50 percent of electrical fires occurring annually in the U.S. could be prevented by AFCIs.
GFCIs: Ground-fault circuit interrupters are recommended for installation in areas where water and electricity are in close proximity, such as bathrooms, garages, kitchens, laundry areas and any outdoor receptacles. A GFCI prevents shock by quickly shutting off power (in as little as 1/40 of a second) to a circuit if the electricity flowing into the circuit differs from that returning, indicating current leakage, or a “ground fault.”
Surge suppressors: A surge-suppression receptacle protects sensitive electronic equipment from transient power surges, as happens when large appliances such as air conditioners turn on and off. These often are installed to protect costly devices such as computers and TVs.
USBs: The newest kind of electric receptacle combines a computer USB port with a traditional outlet. The Electrical Safety Foundation International estimates that more than 10 billion electrical devices in use today are charged via USB cables.
