Epidemiological principles for EMF and EMR studies - Lincoln ...

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Figure 23 shows that the generally presented 8 or 9 horizontal peaks are smoothed
on a graph that actually has 15 or 16 sharp peaks forming each smoothed broad
peaks.
Broadcast engineers have told me and the data confirms that they can design and
build antennas with horizontal and vertical patterns to send most of the signals to
where most of the receivers are. The Fourier phasing of the antenna dipoles and
panels gives undulating patterns that can be focused to some extent to achieve the
design objectives.
Direct measurement RF exposure surveys:
The initial global ubiquitous exposure to RF/MW fields was produced by short-wave
radio and telecommunication and weather satellite signals. RF/MW fields are
produced by many more sources than is commonly known, including high voltage
power lines Vignati and Giuliani (1997). Many modern appliances at home and
work also produce RF/MW radiation fields, including microwave ovens, computers,
TVs and Play Stations, cordless and mobile phones Mild (1980) and Kraune et al.
(2002). Urban and rural areas have detectable and usable RF/MW signals from
many Radio and TV stations, Tell and Mantiply (1980), Mantiply et al. (1997), and
cell phone base stations, Bernardi et al. (2000).
Some occupations are identified as having above average exposures. They include
“electrical and electronic occupations”, radio and radar operators that include
military, police officers and fire fighters, heavy computer users, ICNIRP (1998),
welders (Skotte and Hjollund (1997), Kheifets et al. (1995)) and many industrial
situations where workers spend long period near operating electric motors. Some
office situations are worse than others because of proximity to transformers and
power cables. All occupations using mobile phones or two-way radios, including
police officers, security guards, commercial truck operators, and airport staff.
Commercial and military pilots are exposed to a mixture of ELF and RF/MW fields
from power supplies, visual displays, radios and radars (Nicholas et al. (1998,
2000)). Radar, radio and TV equipment and antenna repairmen are frequently
exposed to higher than average RF/MW radiation.
An early urban RF exposure assessment was carried out by Tell and Mantiply in
the late 1970s. The following graph, Figure 24, shows the spectral analysis from
Portland Oregon showing a number of FM stations. They carried out
measurements to survey 15 cities throughout the United States. The frequency
distribution of personal exposures is given in Figure 25.
The survey of 15 US cities showed that there were scores of RF/MW sources. The
mean exposure at that time was measured as 0.0048µW/cm 2 ranging from
0.002µW/cm 2 in Chicago and San Francisco, to 0.018µW/cm 2 in Boston. However
San Francisco had 2.34%, Chicago 0.4%, Boston 1.5% and Washington DC 2.8%
exposed to ≥1µW/cm 2 . About 1 % of the all populations were exposed to 1µW/cm 2
or more, 200 times the average.