Shielding Electric Fields Emitted from Refrigerators

Because refrigerators generate large electric fields, they should be given a dedicated circuit and the wiring should be shielded with one of the recommended metal conduits in order to block the fields. In addition, the metal refrig­erator cabinet should be bonded to the elec­trical ground. Since the compressor motor and defroster will still produce high magnetic fields, the home should be designed with the refrigerator at least 12 feet away from living and sleeping areas.

Gasketed Electrical Boxes

As discussed in the section on air barriers in Division 7, electrical boxes must be sealed in order to make an exterior wall airtight. You may have experienced the flow of air coming through an outlet on a cold day if the boxes are not installed in an airtight manner. It is neces­sary to prevent air from flowing into the living space from a wall cavity not only for the sake of energy efficiency but also to maintain opti­mal indoor air quality. The following gasketed electrical boxes are designed to create an air­tight seal:

. AirFoil

• Lessco Air Vapor Barrier Boxes

• Allied Moulded Vapor Seal Boxes

Residential Lighting

Residential lighting can also be a source of electromagnetic fields. Here are some point­ers on residential lighting and EMFs:

• Transformers of low-voltage lighting pro­duce a magnetic field. If you use low volt­age lighting, choose remote transformers and locate them in closets at a distance from where you spend a lot of time.

• Fluorescent lighting with ballasts emits magnetic fields that may not be detect­able on an inexpensive gaussmeter. Avoid fluorescent lighting with ballasts in areas where you spend a lot of time, and never locate it on a ceiling below a bedroom. It should also be noted that fluorescent light tubes and compact fluorescent lights con­tain mercury and should be properly re­cycled. Breaking the tubes may release the mercury. (For more information about proper disposal, see

• If you are using recessed can lighting, spec­ify insulation contact airtight (ICAT) cans. These cans save energy and prevent dust and attic gases from filtering into the cans.

• If wiring is run through a metal conduit, the metal housing of the fixture must be in electrical contact with the metal conduit in order to shield the occupied space from electric fields.

Smoke Detectors

The two basic types of smoke detectors are ionizing and photoelectric. The ionizing type contains a radioactive substance called ameri­cium-241. Although the radioactive substance

is shielded, we cannot recommend this type because there is no safe place for disposal once the smoke detector is discarded. Smoke detec­tors are available for use with 9-volt batteries or for hardwiring into the 110-volt household wiring, with or without battery backup. We recommend a hardwired photoelectric system with battery backup, which can be purchased through BRK/First Alert and MCS Referral & Resources. If you are wiring so that your bedroom circuitry can be shut off, it is impor­tant to put the smoke detector on a separate circuit so that it will always remain active. If this circuit is run through a metal conduit, the electric field will be minimal.

Carbon Monoxide Detectors

All gas-burning appliances to which occu­pants are exposed, such as gas ranges and dry­ers, should be tested for carbon monoxide emissions prior to building occupancy. Hie installation of a simple monitoring device en­sures that you will be alerted if a problem with carbon monoxide develops. The device should have battery backup and a digital readout. The following CO monitors meet these criteria:

• Aim S-450 is a portable pocket alarm CO detector unit with a digital readout.

• BRK/First Alert

• NightHawk Carbon Monoxide Detec­tor contains a sensor that samples the air every 2У2 minutes and updates the digital readout.

Further Reading

Becker, Robert O. Cross Currents. J. R Tarcher, 1990. A timely and eloquent warning on the hazards of electronic pollution

Von Pohl, Gustav Freiherr. Earth Currents: Caus­ative Factor of Cancer and Other Diseases. Freeh – Verlag, 1987.

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