When it comes to upgrading or repairing household wiring and electrical systems, homeowners usually call a licensed professional to do the work. But whether you own your home or rent an apartment, bringing the wiring in your residence up to the current National Electrical Code could enhance your safety - every time you flip a switch or plug into an outlet. The NEC sets the minimum electrical standards for essentially all cities, states and municipalities throughout the United States. In all likelihood, your local electrical codes are based on rules set down in the NEC, which is reviewed, revised and updated every three years. Here are some Code highlights that should concern you the most:
Most homeowners are aware that the electrical system must be grounded to the main incoming water pipe - right? But how many know that that alone is no longer sufficient, according to the NEC? Because increasing use of plastic water pipe and non-conducting fittings has made the effectiveness of grounding to plumbing systems questionable, the method does not meet current safety standards. Although water lines still must be used in most circumstances, the Code now states that the home may also require one or more "supplemental grounding electrodes" buried in the house foundation or in the earth outside the home. One or more copper-clad grounding rods several feet in length are often recommended. Local code-enforcement may also require that grounding rods be added to existing homes when new electrical work is done, or if you sell your home.
To increase safety in areas of the home where it counts the most, the NEC requires that ground-fault circuit interrupters or GFCIs, be installed in specific locations. Outlets in so-called "wet" locations such as kitchens, baths and crawl spaces, as well as damp areas like unfinished basements, garages and outdoors, now require GFCI protection. This can be achieved by installing new outlets with built-in GFCIs (identifiable by their "Test" and "Reset" buttons), or by GFCI circuit breakers wired into the house service panel.
The latest innovation beyond GFCIs are arc-fault circuit interrupters, and starting in 2002, these protective wiring devices will be Code-required in circuits serving bedrooms. Arc faults occur when thin electrical wires crimp and fray, which is typically caused by crushing, bending and repeated impact. Why bedrooms? Surveys show that bedrooms are most likely to have exposed lamp cords and electrical devices connected with extension cords - the type of wiring most vulnerable to damage, which in turn leads to arc faults.