American National Standard Techniques and Instrumentation for the Measurement of Potentially Hazardous Electromagnetic Radiation at Microwave Frequencies

This standard sets forth evaluation techniques and instrumentation to determine the existence of a potentially hazardous situation due to electromagnetic radiation. The scope includes hazards to flammable volatile materials and explosive devices. Emphasis is on techniques suitable for measuring power density at microwave frequencies. These techniques are generally applicable only in the far field, but reasonably accurate measurements can be made whenever the following necessary conditions are satisfied. (1) The transmitting antenna and any scattering objects must be in the far field of the receiving antenna. (2) The receiving antenna must be at least several 'aperture diameters' removed from the transmitting antenna and any scattering objects. (3) The transmitting antenna and any sources of multipath scattering must be contained within the main beam of the receiving antenna. Thus, leakage measurements and measurements in the reactive near field are specifically excluded. However, measurements can be made in the radiating near field with a receiving antenna which is small compared to the source antenna if the three conditions above are satisfied.