There were several postings to this forum on this topic in December 1996. Rich Nute listed 16 references.
U.S. levels for non-ionizing radiation have always been based on short term exposure and the thermal heating of internal tissues. Russia used a limit about two orders of magnitude lower based on beliefs with respect to long term exposure to low level radiation, i.e. not a heating issue. In 1976 the published ANSI levels that "should not be exceeded" (ANSI C95.1-1974) were: Mean squared electric field strength 40000V**2/m**2 Mean squared magnetic field strength 0.25A**2/m**2 Power density (skin surface?) 10mW/cm**2 Energey density (skin surface?) 1mWh/cm**2 The ACGIH Threshold Limit Values include suggested limits for RF/Microwave Radiation. However, my copy is three years old, and there is a lot of accompanying information which must be taken into account. George Alspaugh ---------------------- Forwarded by George Alspaugh on 06/05/98 04:31 PM --------------------------- Please respond to dougp%[email protected] (POWELL, DOUG) To: emc-pstc%[email protected] cc: (bcc: George Alspaugh) bcc: George Alspaugh Subject: Need help on non-ionizing radiation Hello Group, I am seeking information on non-ionizing radiation, primarily for workplace safety. I am not actually concerned about the on-going controversy dealing with low-level radiation (VDTs, overhead lines, etc.). This is not to say I don't care, but I am currently interested in high-level non-ionizing radiation which may actually be high enough to cause tissue heating. US standards are probably most applicable but information from any source is welcome. My company, among other things builds High Power RF fixed and variable frequency generators ranging from 100 kHz to 40 MHz at power levels now approaching 120 kW for some frequencies. Many times during test and repair these generators must be operated with the covers open. - What are acceptable limits? - How do I monitor/measure? I have heard stories of a device (probe?) which resembles a bathroom scale and may be connected to a spectrum analyzer. A person or human body model stands on the device. It operates on the idea that electromagnetic radiation received by a human body is conducted out through the ground below. Thanks in advance for any help. Doug Powell Compliance Engineer Advanced Energy Industries, Inc. Ft. Collins, Colorado USA
