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The Electrical Code Design of an electrical system involves applying the standards written into the building code. An electrical code specifies the minimum provisions necessary for protecting people and property from the improper use of electricity and electrical equipment. It applies to both the manufacture and installation of electrical equipment. National Electrical Code The National Electrical Code (NEC) is a set of specifications and standards in the form of a model code that can be adopted into local law by the local governmental entity. Most municipalities and counties in the United States require that residential and commercial electrical wiring conform to the NEC. In some jurisdictions, certain NEC requirements are superseded by local requirements. The NEC was established in 1897 through the combined efforts of insurance, electrical, architectural, and other interested groups. In 1911, the National Fire Protection Association (NFPA) became the sponsor of the NEC and continues to act in this capacity. The NEC is revised every three years to ensure that only the latest safety methods and procedures are used in electrical installations. In the United States, a new edition of the NEC does not become a legal regulation until it’s adopted into law by the local governmental entity. Each new edition must be enacted into law after a formal review of the new release. Generally, review of the new edition takes time and effort, so it’s possible that a city ordinance may still require use of an earlier edition even though a more recent edition has been released. Canadian Electrical Code The Canadian Standards Association (CSA) is the body that publishes and administers the Canadian Electrical Code (CEC). The Canadian Electrical Code Committee develops the Canadian Electrical Code. This committee's members represent regulatory authorities, manufacturers, installers, consumer groups, and the Canadian Electrical Association (utility industry advocate). The CEC establishes safety requirements for electrical work and the installation of electrical equipment operating, or intended to operate, at all voltages in electrical installations for buildings, structures, and premises across Canada. It’s similar but not identical to the National Electrical Code; there are differences. The CEC is revised every four years. When a new edition of the CEC is published, Canada's provinces and territories act to adopt it into legislation, usually with local revisions. As the Code is revised and a new edition is enacted into local law, previously acceptable regulations may become out dated; that is, what was formerly an acceptable electrical installation may no longer be acceptable. The newly enacted Code generally applies to new installations only. Existing electrical installations that don’t meet the current, more stringent regulations still remain permissible as long as they are not regarded as a hazard. A grandfather clause allows outdated electrical installations to remain in use if they are not regarded as hazardous. An outdated installation must be changed only if it’s part of a renovation project. For example, at the time a home was built in 1975, NEC requirements for ground fault circuit interruption (GFCI) protection of convenience receptacles in the kitchen did not exist and GFCI protection was likely not installed. The existing non-GFCI receptacles in the kitchen can remain in use without GFCI protection even though GFCI protection of certain kitchen receptacles was introduced in the 1987 edition of the NEC. If the kitchen was remodeled today, GFCI protection must be added to these outlets. Manufacturing Standards---Today, all electrical equipment, appliances, and devices should meet specific safety standards based on regular product testing. An approved product meets minimum safety standards as determined by extensive testing by an independent testing company or organization. Underwriters Laboratory, Inc. (UL), is a not-for-profit product safety testing and certification organization. It’s the leading third-party certification organization in the United States and the largest in North America. It has been evaluating products in the interest of public safety since 1894. UL is a leading developer of safety standards. The UL Standards for Safety are designed to be compatible with nationally recognized installation, building, and safety codes. ETL Testing Laboratories, Inc., of Cortland, New York, is another internationally recognized, fully independent testing company. In Canada, the CSA develops industrial standards. All electrical equipment for sale in Canada must bear a CSA product certification mark. A UL or ETL Mark on a product (CSA Mark in Canada) indicates that the device or piece of equipment has met mini mum safety standards as determined by extensive testing. Testing of the product is done at the laboratory and by unannounced visits to the manufacturing plant to check ongoing production to ensure the product continues to meet applicable standards. These marks, sometimes known as labels, are found on electrical devices, fixtures, appliances, panelboards, and thousands of other products. The National Electrical Manufacturing Association (NEMA) is the leading trade association in the United States representing the interests of electrical manufacturers. NEMA's member companies manufacture products used in the generation, transmission and distribution, control, and end use of electricity. NEMA has been developing standards for the electrical manufacturing industry since 1926 and is today one of the leading standards development organizations in the world. As such, it contributes to an orderly marketplace and helps ensure the public safety. The Council for Harmonization of Electrotechnical Standards of the Nations of the Americas (founded in 1992) is known in most other countries in North and South America as Consejo de Armonizacion de Normas Electrotecnicas de las Na ciones de las Americas (CANENA). The purpose of CANENA is to facilitate and promote the development of harmonized electro-technical codes and standards and uniform conformity assessment methods. CANENA is not a standards developing organization. It’s an industry-driven organization that encourages the reduction of nontariff trade barriers between the member countries. The ultimate objective of CANENA is to have one standard for a product for all of the western hemisphere, submit the product to a conformance assessment-testing laboratory in one of the countries, and upon successful completion of the testing, receive listings in all countries. Licensing Most municipalities have ordinances (local laws) that require that any person who wishes to engage in the business of in stalling electrical systems must be licensed (usually by the state or province). This means that the person must have a minimum number of years of experience working with a licensed electrician and must pass a written test that deals with the electrical code being used and with methods of installation. By requiring a license, it’s assured that the electrician knows, at a minimum, the code requirements and the installation procedures. There are areas where no laws require that only licensed electricians may install electrical systems and, in effect, there is no protection for the consumer against an un skilled electrician. It’s good practice to insist on licensed electricians for all installations. In some states, electrical contractors must register with the state electrical board. Documentation of current workers' compensation and unemployment insurance coverage is usually required. The individual must sign an acknowledgment of responsibility form to register as an electrical contractor. Permits Most municipalities require that a permit be issued before any electrical installations may be made on a project. A complete electrical construction drawing may also be required for review and approval by a plans examiner before installation begins. This is typically the case on large projects. Other municipalities may not require drawings at all. In general, most municipalities that require electrical permits also require licensed electricians. Municipalities that require a permit will have electrical inspectors who check the project during regularly scheduled visits. Typically, they will inspect the installation after the rough wiring is in but before it’s concealed behind construction materials. When all of the fixtures and devices are installed and wired back to the panel and the service and meter installed, the final inspection is completed. On large projects, it may be necessary for several rough-in and final inspections as electrical work may be done in phases. For example, conduit encased in concrete may have to be inspected before the concrete is poured, and conduit to be built into masonry walls will have to be inspected before the walls are begun. The installer and designer should become aware of when inspections are required and what will be inspected. Also, it’s important that close coordination and cooperation be maintained with the inspector, because the inspector could slow down the progress of the work if the inspection is not made promptly. Whenever possible, the electrical inspector will need to know as early as possible when inspections will be scheduled. Prev: [coming soon] |