As of this writing, no scientific evidence proves conclusively that electromagnetic radiation (EMR) emitted from television or computer monitors poses a health risk to operators. A number of major U.S. companies and Federal agencies are continuing to study EMR emissions that emanate from TVs and video display terminals (VDTs). The question of whether there is a link between EMR emissions and reported symptoms experienced by operators continues to be a topic of debate both within and outside the industry.

All electromagnetic radiation can be classified by frequency from the extremely low (ELF) to extremely high (UV). Extremely high frequency radiation such as ultraviolet and x-radiation is sometimes called "ionizing" because it is powerful enough to effect changes in the atoms of matter it strikes, thus altering their chemical and biological nature (ref). EMR at those frequencies below the ultraviolet band are generally classified as nonionizing because they typically lack the energy to effect changes in atomic structure.

Televisions, computer monitors, and a host of other electrical appliances as well as utility power lines emit a broad range of EMR from 30 cycles up to many gigacycles (109). It has generally been accepted that the kind of biological injury caused by ionizing radiation does not occur by exposure to nonionizing radiation at the atomic level. This conclusion, however, does not apply to molecular-level ionizing effect in the breathable atmosphere.

Televisions and VDTs typically emit electromagnetic radiation at frequencies of 60 hertz and 15-30 kilohertz. The radiation emanates from the cathode ray tube (CRT), the deflection system and transformers, and other coils used in the system. The emissions vary in levels and are measured in milliwatts (.001 watt) for the "E" field and milligause (.001 gauss) for the "H" fields. Contrary to popular belief, most of this type of radiation does not protrude from the front of the screen but from inductive components located near the inside rear or sides of the equipment. Since 1980, manufacturers have been required to add internal shielding to the high voltage transformer used in TVs and VDTs. This requirement, however, primarily addresses compliance with Federal Communications Commission mandates which limit the amount of radio frequency interference produced by such appliances. Radio Frequency Interference (RFI) is limited to avoid jamming noise from penetrating air waves and power lines. RFI requirements are generally not mandated for prevention against possible health hazards.

The intensity of EMR from VDTs is comparable to emissions from other household appliances. These levels of emission are extremely low. The human body absorbs only a minimal amount of radiation below 200 kilohertz. Given the weak energy field source of appliances, this is not generally considered harmful.

In his recent book Currents of Death, (ref) 1989, Paul Brodeur succeeded in reviving the emotionally sensitive issues relating to possible extreme health hazards due to "H" field (magnetic radiation). Mr. Brodeur cites a number of questionable studies which suggest there is overwhelming evidence magnetic emissions from virtually every electrical appliance, as well as power lines, are responsible for an extremely broad spectrum of maladies including cancer deaths and miscarriages. He goes on to suggest a cover-up exists in government and industry to conceal scientific findings which would prove pulsating magnetic fields (ELF), including those from VDTs, are directly responsible for virtually every symptom experienced by operators.

For every study cited in Mr. Brodeur's book, there can be found an equally contrary finding via another study. This may appear to be a cover-up to some; however, what it really amounts to is a continuation of a very long debate among researchers as to specific causes and effects. Dr. Janet Healer (ref) wrote in her 1989 report to the Congressional Office of Technology Assessment:

...studies over the last fifteen years have demonstrated unequivocally that under certain circumstances, the membranes of cells can be sensitive to even fairly weak externally imposed low frequency electromagnetic fields. Extremely small signal changes can trigger major biochemical responses critical to the functioning of the cell." (ref)

There seems little doubt enough evidence has been presented to date to at least justify further investigation into the possible health effects of low level electromagnetic radiation. However, pending further studies, it is premature to identify symptoms ranging from headaches to miscarriage and cancer death to these little understood emissions.

To our knowledge there are no products commercially available which deal with preventing exposure to "H" field magnetic radiation. There are, however, a number of conductive shields which are designed to fit over the front of VDTs and block some of the "E" field electrical emissions. These devices usually double as a glare screen and claim to attenuate a broad range of EMR emissions. In actuality, tests have determined that EMR emissions, whether benign or not, generally emanate from areas far removed from the screen of the computer monitor. Also, these studies have demonstrated that exposure to "E" field electrical emissions at the VDT levels poses the least probability of potential health risks.