Chapter 5.2.2.4 - Electromagnetic Fields

Electromagnetic fields (EMFs) have been the subject of much discussion and considerable
research. Most concern has focused upon the impact of long-term residency
in proximity to electric power high-voltage transmission lines. Considerable
research has been funded by the electric utility industry and conducted through the
Electric Power Research Institute in the United States, and by universities and concerned
science and health organizations worldwide. To date the research has been
unable to establish a causative link between EMF and health effects.

Electric and magnetic fields occur throughout nature and in all living things. Positive
electric charges and negative charges occur in all things electrical (Fig. 2.4).A
handheld or laboratory gauss meter is used to measure the magnetic field in milligauss
(mG), which is one-thousandth of a gauss. Readings have been established for
all major electrical appliances, including electric heating equipment. The fourth
power characteristic of electromagnetic waves tells us that intensity rapidly diminishes
from the designated base distance reading.

Of common electric appliances using a heating element, perhaps the most frequently
used is the hair dryer, which is normally arm’s length at most from the head.
A 1500-W hair dryer employs resistance coils compacted in a circular area approximately
1^1/2 in. in diameter.The milligauss reading, including the fan motor, measured
from a comprehensive representation of products, ranged from a low of 1 at 6 in to
a high of 700. Along with electric razors, this represented the high end of appliance
milligauss readings in daily use within 2 ft of the body (Fig. 2.5).

Radiant panel readings for 1600 W requiring an area of 48 × 96 in that is permanently
ceiling mounted has a milligauss reading of 1.6 at 2 ft, and 0.2 or less at 4 ft,
which is normal sedentary head height. Portable floor heaters tested had a range at
6 in of 5 to 150 mG, which dropped to a range of negligible to 8 mG at 2 ft. Radiant
electric floor heating elements producing 1500 W might encompass anywhere from
100 to 500 ft². In all likelihood, the electric field would be blocked by the panel mass,
and the magnetic field may be self-canceling depending upon the element design
and control. Although the examples provided are representative, each product and

installation should be reviewed with the manufacturer in order to determine relevant
EMF specification information.

Within the built environment, the general guideline is “prudent avoidance” of
long-term exposure to magnetic fields with readings above 4 mG, although no known
harmful relationship has been established. Formal health and safety standards do not
exist because there is no agreement on whether setting standards would do more
harm than good.

Section 2118 of the Energy Policy Act designates lead responsibilities to the
National Institute for Environmental Health Sciences and the U.S. Department of
Energy to oversee EMF health effects research and engineering research, respectively.
The reader looking for current information is advised to contact these organizations,
the Electric Power Research Institute, and the relevant state health services
department.

Electromagnetic fields (EMFs) have been the subject of much discussion and considerable
research. Most concern has focused upon the impact of long-term residency
in proximity to electric power high-voltage transmission lines. Considerable
research has been funded by the electric utility industry and conducted through the
Electric Power Research Institute in the United States, and by universities and concerned
science and health organizations worldwide. To date the research has been
unable to establish a causative link between EMF and health effects.

Electric and magnetic fields occur throughout nature and in all living things. Positive
electric charges and negative charges occur in all things electrical (Fig. 2.4).A
handheld or laboratory gauss meter is used to measure the magnetic field in milligauss
(mG), which is one-thousandth of a gauss. Readings have been established for
all major electrical appliances, including electric heating equipment. The fourth
power characteristic of electromagnetic waves tells us that intensity rapidly diminishes
from the designated base distance reading.

Of common electric appliances using a heating element, perhaps the most frequently
...