August 12, 1993

Editor, Tesla Coil Builders Association News
3 Amy Lane
Queensbury, NY 12804

Dear Sir:

Since 1980 evidence has been accumulating that there may be a cancer hazard associated with exposure to electromagnetic fields, from the 60-Hz fields surrounding power lines up into microwave frequencies. Indeed, the higher the frequency, the stronger the evidence of a hazard to health!

As an industrial hygienist who has given this matter some attention, I am writing to point out that tesla coil builders may be unwittingly exposing themselves - and possibly members of their families - to a cancer hazard. The purpose of this letter is to alert tesla coil builders to this possibility, and to suggest precautions that can be taken to minimize any hazard that may exist.

I should emphasize at the outset that no hazard has been confirmed. But the evidence is growing, and it is particularly strong at high frequencies. Whatever hazard exists arises from the current flowing through the coil. At present, the best way to minimize any hazard is to put distance between yourself and the apparatus when it is energized.

Because most tesla coil builders probably want to be close to their equipment when it is operating, this advice is unlikely to be followed, so here are some alternatives. Limit the amount of time spent close to the coil when current is flowing through it. Keep the periods of operation brief, and repeat them only at extended intervals.

What this advice means is that it probably lowers any cancer risk if equipment is operated only briefly, and at widely spaced intervals of time, than if the apparatus is operated continuously for a long period of time (with someone close to it). This advice applies only to activating the coil. It should be possible to build apparatus with negligible hazard, for example. But the prudent tesla coil builder should treat the testing of apparatus and the operation of the tesla coil as potentially hazardous activities.

It should be pointed out that anyone in the near vicinity of the apparatus may be at risk. Since most tesla coil builders have their apparatus in their homes, this means that members of their family may be at risk, as well. While the tesla coil builder may be willing to take risks with his own health, his spouse deserves the right to make this decision for herself. And the possible risk to children should be considered, as well. The best solution is for the tesla coil builder to activate his apparatus only when other members of his family are away from the house.

The writer of this letter, a Ph.D. physicist who is also a certified industrial hygienist, believes that it will eventually be determined that a cancer hazard is indeed associated with exposure to a.c. electromagnetic fields. The advice in this letter is being offered so that tesla coil builders who may wish to take action to reduce any possible risk to their own heath, or the health of family members, will know what action to take.

The objective of the industrial hygiene profession is to prevent disease that arises from exposure to hazardous or potentially hazardous environmental agents. The advice in this letter therefore comes from an appropriately qualified health professional.

Yours for more healthful environments,

(Editor's note: I have no idea who M. Lundquist is or of the Industrial Hygiene Institute. However, I thought her comments would be of interest to our subscribers.)