Air Ion Measurement

Air Ion measurement has been primarily the concern of meteorologists and geophysicists. Accurate instrumentation was developed by these scientists many decades ago and as a result, we have substantial knowledge of atmospheric electricit and the forces which control it. Though the devices employed by these early investigators were technically fine instruments, they lacked high sensitivity and reliability so necessary for continuous observations. The fundamentals of air ion measuring techniques are thoroughly described in books on atmospheric electricity (1.2) and it is not a purpose of this paper to repeat the principles involved except as they relate to specific problems of instrumentation. It suffices to say that the electronic age has produced new devices to ease the problem of collecting accurate data. It is now possible to systmatize measuring equipment for simultaneous and continuous recording. In the study of biological and physiological response to air ions it is even more important that complete information on ion density, ion size distribution and ion fluctuations are recorded for careful evaluation. There are so many forces at work to balance physiological changes that air ion effects can easily be missed or mistakenly claimed of occasional point observations are relied upon for interpretation. A valid criticism of most clinical and biological studies reported has been the lack of sufficient correlating data on air ion density and size distribution. Presumably equipment has not been readily available, but for test results to have any real meaning accurate density measurements must be included as a part of the experiment.