AIR FORCE JSTARS
The New Killing Fields: Electromagnetic Weapons
Ionizing and Non-ionizing Radiation
Radiation can be broadly
broken into two groupings: ionizing and non-ionizing. Ionizing
means that there is enough energy in the radiation to alter the chemical structure of matter
upon its absorption by knocking off electrically charged particles (ions). Non-ionizing
means that there is not enough energy in the radiation to create ions. Instead, the energy
is usually absorbed as heat. RFR is a form of non-ionizing radiation.
Because of their extremely
high frequencies and energies, X-rays and gamma rays are
electromagnetic types of "ionizing" radiation, as are many types of high-energy,
high-velocity sub- atomic particles that result from nuclear processes. When ionizing
radiation interacts with living structures, it can cause severe damage. The chemical bonds
of molecules struck by high energy particles can be broken, causing parts of the
molecules to be split off, often as reactive charged particles (ions). These ions can
promote additional chemical and physical reactions. If the absorbing molecules are DNA or
other genetic materials, cellular metabolism can be interfered with and the cell's ability to
reproduce itself can be destroyed or caused to malfunction (the latter sometimes leading
to cancers). (Barrett, see references.)
of lower frequency levels and energies, such RFR and EMFs
associated with radio systems, do not cause ionization and consequently are referred to
as "non-ionizing" radiation. If absorbed at all, this type of energy is absorbed as heat.
Unless generated at extremely high power densities and at just the right resonance
frequencies so as to produce large amounts of heat resulting in actual burns, the frequency
and resulting energy levels of non-ionizing radiation are almost always too low to affect
biological materials. Non-ionizing radiation is not known to damage DNA as can ionizing
radiation and generally has not been shown to cause irreversible changes that can
accumulate over time (Yost, see references).
There is one potential
problem, however. Sometimes in a complex organic molecule short,
linear groups of atoms extend off of a main chain or body of the complex. It has been
shown that at the right frequencies, these extensions can be excited by strong,
non-ionizing energy so as to cause frequency resonance to occur. The extension can then
vibrate and on occasion break off, altering the structure of the molecule. This is the only
other known interaction between non-ionizing radiation and biological structures. It is
considered to be a rare phenomenon, as the frequency of the radiation must exactly match
the natural resonance of the molecule and the power density must be very high. (Barrett,
Why the Concern?
Most scientists maintain
that RFR and lower frequency EMFs such as those associated
with wireless communications systems generally do not produce adverse health effects in
humans because they are non-ionizing in nature and normal exposures are controlled so
as not to result in thermal effects. Other researchers, however, note the possible molecular
resonance problem described above and propose that continuous low-level exposures or
exposures in combination with other chemicals may cause health problems that are not
immediately evident. These researchers suggest that extra care should be taken until more
The media continue to
report the work of these researchers and the public exhibits a sharp
interest in the debate between the two sides. Some members of the public believe that
even the remotest possibility of a health hazard constitutes grounds for forming public
policy and regulations for facilities using radiofrequency radiation and generating
electromagnetic fields. Consequently, there is often keen public interest in proposals for
new wireless cell sites and facilities.
ANSI, NCRP, and IRPA Radiation Protection Guidelines
"Both private organizations
and government agencies have proposed guidelines that limit
exposure to nonionizing radiation. These standards can be divided into broad categories:
emission standards, which set limits on the incidental (nonpurposeful) radiation emanating
from a device; and exposure standards, which set limits on the radiation power density to
which a person may be exposed. Emission standards limit unwanted leakage from devices
such as microwave ovens that should contain the radiation inside the device or that have
shielding to protect operators and others from exposure during normal operation. Exposure
standards limit exposure of persons to radiation present in the environment, for example
from a radio transmitter" (Yost, see references).
There is no official,
mandatory federal standard for radiation exposure protection in the
United States. The official guideline for facilities regulated by the Federal Communications
Commission (FCC) is currently the 1982 American National Standards Institute (ANSI)
guideline. The 1982 ANSI guidelines recommend exposure limits covering RFR from 300
kHz (kilohertz) to 100 GHz (gigahertz). The guidelines recognize that the human body
absorbs radiofrequency energy at some frequencies more readily than at others. The most
restrictive limits are in the frequency range of 30-300 MHz. However, the wireless
communications systems discussed in this paper operate in the frequency range of 800 to
2200 MHz -- frequencies outside of the most sensitive range.
ANSI has adopted C95.1-1992,
a revision of the 1982 standard, and the FCC has proposed
its adoption. The new standard "contains a number of significant differences from
guidelines and recommendations issued by ANSI in 1982. In many respects, the 1992
guidelines are more restrictive in the amount of environmental RF exposure permitted, and
they also extend the frequency range under consideration to cover frequencies from 3 kHz
to 300 GHz. The new 1992 guidelines specify two sets of exposure recommendations, one
for 'controlled environments' (usually involving workers) and another for 'uncontrolled
environments' (usually involving the general public). (FCC 93-142).
For controlled environments,
the 1992 ANSI/IEEE standards recommend maximum power
density levels calculated by dividing frequency by 300 (f/300). For example, for a cellular
frequency of 888 MHz, the standard would be calculated by dividing 888 by 300, yielding
an exposure level of 2.96 mW/cm2 (milliwatts per square centimeter). For uncontrolled
environments, the revised standards recommend maximum power density levels calculated
by dividing frequency by 1500 (f/1500). As a result, for the same cellular frequency of 888
MHz, the exposure standard for the uncontrolled environment would be 0.592 mW/cm2
(888/1500). Thus, for both controlled and uncontrolled environments, the ANSI/IEEE
exposure standards for wireless communications are dependent upon the technologies
In addition to the ANSI
standard, there are two other widely discussed public exposure
standards: that of the National Council on Radiation Protection (NCRP) and that of the
International Radiation Protection Association (IRPA). Because the NCRP standards cover
the 1500 MHz to 1011 MHz frequency range and the IRPA standards cover the 2,000 MHz
to 1011 MHz frequency range, these two exposure standards apply only to the upper
portions of the PCS frequency range. They do not apply to the cellular or ESMR
technologies, whose frequency ranges lie between 800 and 900 MHz.
The NCRP is a non-profit
corporation chartered by the United States Congress to, among
other things, develop information and recommendations concerning radiation protection.
The guidelines issued by the NCRP specify a level of 1 mW/cm2 (milliwatt per square
centimeter) for the exposure of the general public in the frequency range listed above.
The IRPA is a non-governmental
international organization representing most of the
national radiation protection societies in the world. These recommendations form part of
the World Health Organization (WHO) United Nations Environmental Programme (UNEP).
IRPA guidelines for public exposure also recommend 1 mW/cm2 for the frequency range
listed above. It should be noted that both the NCRP and IRPA exposure standards are
more restrictive than the revised ANSI standards for PCS frequencies above 1500 MHz in
uncontrolled environments and for all PCS frequencies in controlled environments.
Some states, including
Massachusetts, New Jersey, Oregon, and Washington, as well as
some local jurisdictions have adopted their own radiation guidelines.
The levels of RFR to which
the public is routinely exposed are far below the levels
necessary to pose a health risk. A 1989 report by the Office of Engineering and
Technology stated that the U.S. Environmental Protection Agency estimates that in seven
metropolitan areas studied across the United States, 98 to 99 percent of the population is
exposed to less than 0.001 mW/cm2 of radiation. The standards listed above are
considerably more restrictive than the exposure levels that the majority of the public
Additionally, the 1982
ANSI guidelines for radiation exposure indicate that devices
operating on less than seven watts of power at frequencies less than 1,000 MHz will not
cause immediate thermal effects. Cellular mobile phones operate between 0.6 and three
watts of power at frequencies between 800 and 900 MHz, ESMR mobile communicators
operate between 0.5 and 1.5 watts of power in the 800 MHz frequency band, and PCS
mobile communicators are anticipated to operate on no more than 1 watt of power at
frequencies between 1,850 and 2,200 MHz, all falling well below the seven watt threshold.
Typical cell sites, including
monopoles, roof-mounted antenna sites, and building-mounted
antenna sites, emit a maximum of 3,000 watts of effective radiated power (ERP) (the power
supplied to an antenna multiplied by the relative gain of the antenna in a given direction). In
comparison, radio broadcasting towers emit roughly 100,000 watts ERP, and television
broadcasting towers emit approximately 5,000,000 watts ERP. The radiation emitted from
these broadcasting sources decreases according to the inverse square principle. As a
result, exposure to radiation decreases as distance from broadcasting sources increases.
Ongoing and Future Research
Although many studies
have been conducted examining the effects of RFR and EMFs on
animals and humans, scientists have been unable to reach consensus on the results for
various reasons, including: difficulty in interpreting the extrapolation of studies performed
on animals and cells to humans; difficulty in explaining the effects of natural influences,
such as the earth's magnetic field; difficulty in controlling crucial variables in the study,
such as the amount of energy absorbed by test organisms; difficulty in replicating and
generalizing results obtained at specific power levels, frequencies, and modulation
patterns, to other situations; difficulty in distinguishing between slight normal human
changes and subject variations; and difficulty in agreeing on the results and methodologies
of epidemiological studies.
While some studies suggest
that long-term exposure to some forms of RFR may cause
adverse health effects in humans, many other studies do not. According to a report
published in 1994 by the United States General Accounting Office, both the Food and Drug
Administration (FDA) and the Environmental Protection Agency (EPA) agree that the
information from the most current studies is insufficient to determine whether the risks are
substantive, if present at all.
In fact, some cities,
such as the City of San Diego, have addressed this issue by
distinguishing between actual and perceived health hazards when performing CEQA
(California Environmental Quality Act) review. The city recognizes that the public's fear of
the unknown sometimes causes "perceived health hazards." Since studies have been
found inconclusive in relation to the thresholds established by the ANSI standards, the city
does not identify EMF impacts on human health as significant. Nonetheless, the policy of
the Environmental Analysis Section (EAS) of the Development and Environmental Planning
(DEP) section of the Development Services Department (DSD) is to disclose the presence
of EMF sources, and advise "prudent avoidance," where possible. An example of prudent
avoidance would be to place power lines or other sources of radiation in places of
low-intensity human uses, such as parking lots. Concurrently, the City of Poway has
suggested that required buffer distances would be helpful in separating such facilities from
areas where people tend to cluster, such as schools, residences, parks, and day care
RFR Research Related to Wireless Communications
In 1991, the California
Public Utilities Commission (CPUC) opened Investigation 91-01-012
to consider whether the CPUC should adopt a role to mitigate potential health effects, if
any, of EMFs created by electric utility power lines and cellular facilities. Consensus was
reached that EMF issues involving electric utilities and cellular utilities should be
addressed separately. A cellular steering committee composed of five individuals was
established with one individual representing each of the following agencies: the CPUC's
Commission Advisory and Compliance Division (CACD), the Division of Ratepayer
Advocates (DRA), the California Department of Health Services (DHS), the Cellular Carriers
Association of California (CCAC), and the "Citizens Concerned About Telecommunications
EMF." In July 1993, the steering committee held an informational workshop addressing
three issues: levels of cellular utilities' EMF and RFR impacts, issues for further
consideration, and interim safety measures.
In December 1994, the
CACD released a summary of the workshop. The report concluded
that although little is known about potential health hazards related to EMF and RFR
exposure levels, cellular power densities have been found to be consistently below present
exposure standards. In the absence of scientific evidence linking cellular exposure levels to
human health risks, the steering committee decided not to adopt a specific numeric set of
EMF and RFR exposure standards associated with cellular facilities. However, recognizing
that future scientific research may provide more definitive information, the CACD adopted
the responsibility to serve as a clearinghouse of EMF and RFR research and to hold
periodic workshops informing interested parties of new findings.
On November 8, 1995, the
CPUC released Decision 95-11-017. The decision (1) adopts the
CACD's workshop report (except for a proposed interim measure requiring cellular utilities
to consider alternative cell site locations and restrict access to their cell sites through
warning signs or physical barriers); (2) approves the designation of the CACD to hold
workshops as additional health information becomes available and requires that the
workshop results be reported to the CPUC through the resolution process; and (3) closes
In November of 1994, the
United States General Accounting Office published a report addressing
the status of scientific knowledge on the effects of RFR caused by cellular telephones. The report
found that no long-term studies on low levels of radiation from cellular phones have been
completed, and that the research conducted on other sources of low-level RFR are inconclusive.
The report further determined that both epidemiological and laboratory studies are needed to
ascertain whether portable cellular phones produce adverse health effects. Two such studies are
1. In 1991, Motorola,
Inc., contracted with a prominent U.S. research company to study the
effects of analog and digital signals from cellular telephones on animals and cells. Results are
expected to be released in late 1995 or early 1996.
2. In 1993, due to public
anxiety that portable cellular phones cause adverse health effects, the
Cellular Telephone Industry Association (CTIA) allocated $15 to $25 million to study the safety of
cellular phones for three to five years, including the effects of analog and digital radiation at
cellular and PCS frequencies. The CTIA and other industry representatives established a Science
Advisory Group on Cellular Telephone Safety to perform this research through epidemiological
studies, cell cultures, animal testing, and genetic research. The research will be submitted to a
scientific peer review coordinated through the Harvard University Center for Risk Analysis. This
research will be open for federal participation in order to provide further objectivity.
The federal government
also is undertaking research that focuses specifically on cellular
telephone safety issues. The National Cancer Institute has begun an epidemiological study of
people with brain cancer to ascertain whether there is a statistical relationship between cancer
and the use of cellular telephones. It is anticipated that this study will be completed between
1998 and 1999.
The research conducted
up to the present is considered inconclusive, but important questions
have been raised about the possible relationship between health complications and the exposure
to radiofrequency radiation and electromagnetic fields. The studies cited above, in combination
with other human and laboratory studies, could provide the kind of comprehensive research
needed to determine the safety of wireless communications devices.
RFR and EMF Information Sources
In January of 1995, the
Department of Energy released a booklet entitled Questions and
Answers about EMFs, published by the department's Research and Public Information
Dissemination (RAPID) program. The RAPID program was established in 1992 as a five
year, $65,000,000 program to study if exposure to EMFs causes adverse health effects. To
order free copies, call 1 (800) 363-2383, or call Alicia Hillery for bulk orders at (202)
For additional information
on EMFs, Planning Advisory Service Report #435,
Electromagnetic Fields and Land-Use Controls, by David Bergman, Louis Slesin, and
Matthew Connelly (Chicago: American Planning Association, 1991) can be ordered through
the American Planning Association's Planners Bookstore, 122 S. Michigan Ave., Suite
1600, Chicago, IL 60603; (312) 431-9100. Additionally, the ANSI Standards, also known as
IEEE Standard for Safety Levels with Respect to Human Exposure to Radio Frequency
Electromagnetic Fields, 3 kHz to 300 GHz, 1992 (ANSI/IEEE c.95.1-1992), and
Recommended Practice for the Measurement of Potentially Hazardous Electromagnetic
Fields - RF and Microwave (ANSI/IEEE C95.3-1992) are available through the American
National Standards Institute, 11 W. 42nd St., New York, NY 10036; (212) 642-4900.
ABBREVIATIONS OF TERMS
Amperes per meter
ANSI American National Standards Institute
BTA Basic Trading Area
CCAC Cellular Carriers Association of California
CDMA Code Division Multiple Access
CDPD Cellular Digital Packet Data
CEQA California Environmental Quality Act
CFR Code of Federal Regulations
CGSA Cellular Geographical Service Area
CPUC California Public Utilities Commission
CTIA Cellular Telecommunications Industry Association
DEP Development and Environmental Planning
DHS Department of Health Sciences
DRA Division of Ratepayer Advocates
DSD Development Services Department
EAS Environmental Analysis Section
EIR Environmental Impacts Report
ELF Extremely Low Frequency
EMF Electromagnetic Field
EPA Environmental Protection Agency
ESMR Enhanced Specialized Mobile Radio
FCC Federal Communications Commission
FDA Food and Drug Administration
G.O.159 (A) General Order 159 (A)
IEEE Institute of Electrical and Electronic Engineers
LCP Local Coastal Plan
MSO Main Switching Office
MTA Metropolitan Trading Area
mW/cm2 Milliwatt per square centimeter
PCS Personal Communications Services
RFR Radio Frequency Radiation
RSA Rural Statistical Area
SMR Specialized Mobile Radio
SMSA Standard Metropolitan Statistical Area
TDMA Time Division Multiple Access
V/m Volts per meter
WTB Wireless Telecommunications Bureau
Analog Technology (see
Analog technology replicates and amplifies voice messages as they are carried from the
transmitting antenna to the receiving antenna. Traditionally, cellular phone systems have
used analog transmission signals.
A device used in communications which transmits or receives radio signals.
A clearly defined range of radiofrequencies dedicated to a particular purpose.
California Public Utilities
Governmental agency which regulates the terms and conditions of public utilities in the
State of California. Of the three wireless communications services discussed in the Issues
Paper, the CPUC presently regulates only cellular service providers.
A segment of a frequency band. Also referred to simply as ìfrequency.î
Locating wireless communications equipment from more than one provider on a single site.
A public radio service in which a single licensee provides one-way or two-way service to
A land use facility supporting antennas and microwave dishes that sends and/or receives
radiofrequency signals. Communications facilities include structures or towers, and
Digital technology converts voice and data messages into digits that represent sound
intensities at specific points of time and data content. ESMR and PCS service providers
employ digital technology, and cellular providers are rapidly converting to digital as well.
A dish-like antenna used to link communications sites together by wireless transmission
of voice or data. Also called microwave antenna or microwave dish antenna.
Effective Radiated Power
The power supplied to an antenna multiplied by the relative gain of the antenna in a given
The local electric and magnetic fields that envelop the surrounding space. The most
ubiquitous source of EMFs is from the movement and consumption of electric power, such
as with transmission lines, household appliances and lighting.
The federal agency responsible for licensing and regulating wireless communications
providers. The FCC has primary regulatory control over communications providers through
its powers to control interstate commerce and to provide a comprehensive national system
in accordance with the Federal Communications Act.
The number of cycles made by electromagnetic radiation in one second, usually
expressed in units of hertz (Hz).
A unit for expressing frequency which is the number of times a wave-like radio signal
changes from maximum positive to maximum negative charge per second. 1 Hz = 1 cycle
per second. 1 kilohertz (kHz) = 1,000 Hz; 1 megahertz (MHz) = 1,000 kHz or 1,000,000
Hz; 1 gigahertz (GHz) = 1,000 MHz or 1 million kHz or 1 billion Hz.
Disturbances to reception caused by radiofrequency waves or other electric fields.
Electromagnetic radiation frequencies from 3 GHz to 300 GHz; highly directional when
used for radiofrequency transmissions. Uses relatively low transmitter power levels when
compared to other forms of transmission.
A structure composed of a single spire used to support communications equipment.
Electromagnetic waves of low frequency, long wavelength, and low photon energy unable to
cause ionization (i.e., to remove an electron from an atom).
An antenna or array of antennas designed to concentrate a radio signal in a particular area.
Panel antennae are typically flat, rectangular devices approximately six square feet in size.
Also called directional antennae.
The magnitude of the electromagnetic energy flux density at a point in space, in power per
unit of area (measured in milliwatts per square centimeter or mW/cm2).
A generic term referring to communication of impulses, sounds, and pictures through
space by means of electromagnetic waves.
Electromagnetic radiation in the portion of the spectrum from 3 kHz (kilohertz) to 300 GHz
Any communications facility which is designed to blend into the surrounding environment.
Examples of stealth facilities may include architecturally screened roof-mounted antennas,
building-mounted antennas painted to match the existing structure, antennas integrated
into architectural elements, and antenna structures designed to look like light poles. Also
called concealed antennas.
The distance between points of corresponding phases of a periodic wave of two constant
cycles. Wavelength = wave velocity/frequency.
An antenna that transmits signals in 360 degrees. Whip antennae are typically cylindrical
in shape and are less than 6 inches in diameter and measure up to 18 feet in height. Also
called omnidirectional, stick, or pipe antennas.