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The goal of this project is to advance the state of the art of RFR dosimetry to a level of sophistication where computer graphically generated, high-resolution SAR distributions can be obtained and displayed with anatomical features for any section of the human body. Procedures are to be developed to allow modeling of the realistic exposure conditions for whole-body or partial-body irradiation due to spatially uniform or nonuniform (far-field or near-field) EM fields that are CW, pulsed, or transient in nature. Effects will also be directed at improving thermal models of the human body so that expected temperature distributions due to RFR exposure can be predicted and displayed graphically. Participants have generated recommendations for research in subspecialty areas relevant to the above, such as standard models of humans and animals, graphical display methods, numerical algorithms; validation of computer-generated data, extrapolation of SAR data to thermal physiology, and others., Prepared in collaboration with AUSA, Cupertino, CA.

Pacemaker responses were measured on twenty-one different types (manufacturers and models) of devices, exposed free-field and simulated-implant configurations. Relative interference thresholds were vastly different; the most sensitive pacemaker being adversely affected at electric (E) field levels as low as 10 volts per meter and the least sensitive pacemaker being relatively free of interference at levels as high as several hundred volts per meter. In many cases the real time E-field level around radiofrequency radiation (RFR) emitters manifests itself as a pulsed or pseudo-pulsed (changing E-field) signal which can adversely affect cardiac pacemakers and is potentially hazardous for other types of medical prosthetic devices. These empirical findings demonstrate the need for continuing awareness of potential RF interference situations and provide reasonable evidence that through such awareness many of the potential EMI problems can be effectively circumvented., Pub. in Fundamental and Applied Aspects of Nonionizing Radiation, p351-363 n.d.

The response of two Model EFS-1 field-strength meters was measured when exposed to 10, 20, 30, 40, and 50 MHz fields. This electric field sensor is advertised as responding directly from 10 kHz to 200 MHz. Tests were completed for continuous wave and pulsed square wave exposure conditions. These test results indicate that the EFS-1 would be a useful radiofrequency radiation field sensor.

The most common biological effect of overexposure to radiofrequency radiation (RFR) fields may be described as an acute thermal burden. The extent of the effect depends primarily on the time rate of transfer of the energy to the biological specimen. The depth of penetration and the amount of incident energy absorbed varies as a function of the frequency of the incident radiation. As the frequency decreases, the penetration of energy into biological tissue becomes deeper; however, wavelengths in the kilohertz (kHz) and lower megahertz (MHz) regions are so long with respect to the physical dimensions of the human subject that energy absorption is negligible. The purpose of this research was to measure the energy absorption in human phantoms when exposed to high frequency (HF) band fields.

Pub. in Radio Science, v14 n6S p1-4 Nov-Dec 1979.

A Dewar calorimeter system has been built and demonstrated to be a practical instrument for determining the absorbed power of rodents exposed to radiofrequency fields. Some of the potential pitfalls of this technique have been pointed out and solutions are presented in this paper.

The effect of radiofrequency (RF) radiation emission on cardiac pacemaker function is a unique bioeffects phenomenon. Dependent of the pacemaker type and design, and on the frequency, peak E-field intensity, pulse width, and effective pulse repetition rate of the incident RF signal, the pacemaker may cut off completely, revert to a fixed interference-rejection mode of operation, experience intermittent disruption, or be totally unaffected. Experimental evidence is presented for a wide variety of tests conducted under controlled laboratory conditions and in the vicinity of numerous types of RF emitters prevalent in U.S. population centers. These test results are discussed in terms of their clinical significance, technical feasibility of designing pacemakers to avoid electromagnetic interference, and appropriate design goals to achieve overall RF environmental compatibility.

The power absorbed by biological systems and thus the biological insult vary as a function of the frequency of the incident radiofrequency (RF) field. To define the effects of RF radiation on man, it is necessary to quantitate the absorbed power in man and experimental animals over a broad range of frequencies. Prolate spheroid phantoms representing man and monkey were used to determine the absorbed power by differential power measurement techniques, and these data were compared with theoretical results. Power absorption measurements were performed on live monkeys, and these results were compared with the results using phantoms to determine the adequacy of the prolate spheroid model. The results indicate the theory to be excellent for predicting power absorption in the phantom, but the more complex ellipsoid model will be required to predict power absorption in primates.

This review examines the characteristics of millimeter-wave radiofrequency radiation, predicts possible exposure levels, and analyzes the millimeter-wave bioeffects literature. Data gaps and possible mechanisms of millimeter-wave bioeffects are examined. (Author)

Tests were performed to determine the effect of 3050 MHz radio- frequency radiation on cardiac pacemakers. Five pacemaker models were implanted in large dogs and tested in each of two laboratories. The electrocardiographs of each animal were continuously monitored for various exposure conditions. Most of the pacemakers exhibited some electromagnetic radiation interference (EMI) under certain conditions of these tests. The most sensitive unit, of those tested, cut off at approximately 100 V./m. at pulse repetition frequencies less than approximately 35 pps--while one pacemaker exhibited no effects from EMI throughout these tests.

Tests were performed to measure the effect of pulsed 450 and 3100 MHz RF radiation on cardiac pacemakers. All models were tested in both a free-field and a simulated-implant configuration and were continuously monitored during testing. Most of the models exhibited some type of electromagnetic interference under some conditions of the tests, although five recent, different models were unaffected under all conditions of these tests.