Electrical components on an electrical engineer’s plans
The safe use of electrical appliances and equipment depends on reliable and effective electrical engineering solutions. This requires careful planning together with specification of approved materials and equipment that will safeguard people and property from hazards that might arise from the use of electricity. This includes provision for tamper-resistant receptacles to be installed at power outlets so that plugs or electrical equipment can be used safely, without any unnecessary risks.
In the U.S., the primary legislation for electricity is a National Fire Protection Association (NFPA) code: NFPA 70 National Electrical Code, 2017 Edition. While many states and cities have adopted the NEC, any local variances or local codes must be followed by electrical engineers when they design systems for buildings.
Chicago has adopted the newly updated NEC and the 2018 edition of the Chicago Electrical Code (CEC), which is part of the city’s Municipal Code, is based on the NEC.
The NFPA also publishesNFPA 70: National Electrical Code with Chicago Amendments, which incorporates annotations indicating changes made to NFPA 70 by the Chicago City Council. In its entirety, the amended version of NFPA 70 forms the CEC, which is Title 14E Electrical Code of the Municipal Code of Chicago.
There are 10 chapters in the Code, including 14E-4: Equipment for General Use. Article 406 of 14E-4 is titled Receptacles, Cord Connectors, and Attachment Plugs (Caps), with 406.12 specifically covering tamper-resistant receptacles.
CEC 406.12 Tamper-Resistant Receptacles
CEC 406.12 lists tamper-resistant receptacles of the non-locking type. These are specifically for use with 15-ampere and 20-ampere, and/or 125-volt and 250-volt electrical systems.
The areas stipulated in the Code are:
- Dwelling units, in areas that are specified elsewhere in the Code
- Guest rooms and suites of both hotels and motels
- Childcare facilities
- Preschools as well as elementary education facilities
- Business offices, waiting rooms, corridors and so on in medical and dental offices, and in clinics, and outpatient facilities
- Assembly occupancies that are designed or intended for gatherings of at least 100 people for a range of purposes that include:
- Eating and/or drinking
- Amusement or entertainment
- Awaiting transportation
Both entire buildings and portions of buildings or structures are included and these include auditoriums, gymnasiums, skating rinks, assembly halls, conference rooms, courtrooms, dance halls, mortuary chapels, museums, and restaurants.
Receptacles that are located more than 5½ ft or 1.7 m above the floor do not have to be tamper-resistant.
The areas where tamper-resistant receptacles should be located in dwelling units are specified in Article 210 Branch Circuits and Article 550 Mobile Homes, Manufactured Homes, and Mobile Home Parks.
Additionally, it is a requirement that tamper-resistant receptacles or tamper-resistant covers should be installed or used in pediatric locations that are designated for general care. This includes patient rooms, playrooms, activity rooms, and bathrooms in pediatric units, or comparable areas that have a similar risk factor. Ultimately, the governing body will determine the risks.
Tamper-Resistant Receptacles for Dwelling Units
The section on Dwelling Unit Receptacle Outlets (CEC 210.52) gives the Chicago City Council’s requirements for 125-volt, and 15- and 20-ampere receptacle outlets for dwelling units. These range from single units that provide “complete and independent living facilities” for one or more people, and include permanent provision for living, sanitation, cooking, and sleeping. In effect, they include any building where a person or family would live including houses and apartments.
Because the voltage and amperage is the range that applies to tamper-resistant receptacles, all the receptacles required by 210.52 must be tamper-resistant. Furthermore, these receptacles are in addition to receptacles that:
- Form part of a luminaire or appliance.
- Are controlled by wall switches in habitable rooms, each of which must have at least one wall switch. Receptacles controlled by wall switches are allowed in place of lighting outlets, except in kitchens and bathrooms.
- Are located in cupboards or cabinets.
- Are located more than 5½ ft or 1.7 m above the floor.
Electric baseboard heaters equipped with outlets that have a separate assembly or factory-installed receptacle outlet may be permanently installed but they may not be connected to heater circuits.
In addition to the general provisions of 210.52, the areas specified for receptacles in dwelling units relate to:
- Countertops and work surfaces in kitchens, pantries, breakfast and dining rooms, and similar areas.
- Bathrooms, that are required to have at least one receptacle within 3 ft or 900 mm of the outside edge of basins, either on the wall or on a partition adjacent to the basin, or on the face or side of the basin cabinet. It must not be below the basin countertop or top of the basin.
- Outdoor areas including balconies, porches, and decks.
- Laundry areas.
- Basements, garages, and accessory buildings that are equipped with electrical power.
- Hallways that are 10 ft or 3 m or longer. These must have at least on receptacle outlet.
- Foyers that aren’t part of hallways and are at least 60 sq ft or 5.6 sq m in size. These must have a receptacle in each wall space.
Receptacles for small appliances are also covered.
Tamper-Resistant Receptacles for Mobile Homes
Mobile Homes, Manufactured Homes, and Mobile Home Parks (CEC 550.13) provides the Chicago City Council’s requirements for receptacle outlets as they apply to these dwelling types.
Like the dwelling unit receptacle outlets specified previously, the voltage and amperage of these receptacles are such that they have to be tamper-resistant.
This section of the Chicago Electrical Code details:
- Compliance for grounding-type receptacle outlets.
- Where ground-fault circuit interrupters (GFCI) must be located:
- In bathrooms
- In kitchens where receptacles serve countertops
- Near sinks where receptacles should be installed within 6 ft or 1.8 m of the sink’s outer edge
- The need for grounding-type receptacle outlets for each fixed appliance that is plugged in.
- Specific areas where receptacle outlets are required and where they should be installed.
- Where pipe-heating cable outlets should be located.
- Receptacle outlets that are not allowed including within or directly above bathtubs or showers.
- Receptacle outlets that are not required, for instance directly behind doors that open fully against a wall surface.
Electrical Designs that Incorporate Tamper-Resistant Receptacles
New York Engineers’ electrical engineers prepare electrical designs for all construction needs, including lighting, heating, and ventilation. This includes incorporating tamper-resistant receptacles required by the NEC and local codes like Chicago’s CEC 406.12.