The Safety of the HAARP Facility

HAARP has been Designed to Ensure Safety
with respect to Electromagnetic Fields

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The Inherent Safety of the HAARP Design

• The antennas used in the HAARP array are horizontal dipoles. The field associated with such antennas does not propagate (travel) well over ground and dies out rapidly as the distance increases.
• The HAARP Antenna array employs a ground screen and the antenna elements are energized in such a way as to form a pattern upward, not outward as in more conventional transmitting sites like the Voice of America or normal AM/FM/TV broadcast stations.
• The HAARP design spreads fundamental transmitter power over multiple antennas instead of concentrating it in only a few antennas. This produces a lower field on the ground without affecting the desired field overhead.
• The HAARP antenna array is located 0.7 mile from the closest point of public access. The power density at this point is approximately 20,000 times lower and safer than current safety standards, adopted by ANSI/IEEE.

HAARP Fields are Lower Than Adopted Safety Standards

The safety standard specifies that the power density in milliwatts per square centimeter (mw/$cm2$) shall be less than 180/$f2$ (where f is the frequency in MHz). For the frequency range used in the HAARP IRI, the maximum safe level of power density can be calculated to range from 23 mw/$cm2$ at 2.8 MHz to 1.8 mw/$cm2$ at 10 MHz.

Extensive computer modelling prior to construction predicted that these field strength levels would not be exceeded anywhere on the site, even directly under or at the edge of the ground screen. Nevertheless, an exclusion fence was placed around the array for additional safety. Measurements made during the period January - April 1995 on the prototype IRI at several frequencies, have confirmed that the electromagnetic field (scaled to the fully built IRI) would be below the established standard, as predicted. Within the temporary operations trailers, located about 100 yards from the antenna array, measurements indicate that the power density for the full IRI never will never exceed 0.03 mw/$cm2$ which is at least 60 times safer than the standard. At other locations on the site, the field will be considerably less. Measurements made at the site entrance, (the closest public approach to the HAARP IRI) indicate that the the electromagnetic field will have a power density of less than 0.00007 mw/$cm2$, a value that is approximately 27,000 less than (and safer than) the standard. Measurements, made along the Tok Highway confirmed that the field continues to decrease in a regular manner, as the distance from the array increases.

The greatest theoretical power density that could reach any point on the ground after reflection from the ionosphere for the full size IRI, (considering only distance travelled and none of the other loss factors that are nearly always present) is on the order of 0.1 microwatt per square centimeter, a level that is approximately 200,000 times lower than the safety standard level. In an attempt to confirm these predictions, measurements of field strength due to reflected signal from the ionosphere were made at various times during the period January - April 1995 using automatic monitoring equipment at locations in Glennallen, Anchorage and Prudhoe Bay. (At these sites, the only available field would be from ionospherically reflected signals.) None of the measurements (scaled to the full IRI) even approached the maximum, theoretically possible signal and most of the time, there was no signal observed.

Comparison of HAARP fields with other sources of RFR

An amateur radio operator, for example, operating his/her equipment completely in compliance with FCC rules in the HF band, is capable of generating an electromagnetic field exceeding 0.0003 mw/$cm2$ within a radius of 500 or more feet of the antenna. Standard AM broadcast stations can produce electric fields exceeding 0.0003 mw/$cm2$ at all points within a radius of one mile of the antenna and fields above 0.03 mw/$cm2$ at ranges of a quarter mile.

While the power densities in each of these examples are well below the safety standard, they are still many times greater than the power density that HAARP would produce at any public location. The HAARP design assures that the public is never exposed to fields anywhere near the level of the safety standard.

The Environmental Impact Process that was conducted during 1992 and 1993 for the HAARP project considered these and many other factors related to RFR health and safety. The conclusions presented in the final EIS document, published in July 1993, prior to beginning any construction of the HAARP facility, were that there would be no significant adverse effects on humans or animals, and those conclusions remain valid today.

[1] IEEE Standard for Safety Levels with Respect to Human Exposure to Radio 
    Frequency Electromagnetic Fields, 3 kHz to 300 GHz, IEEE C95.1-1992.

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