REPORT OF PRELIMINARY MEASUREMENTS OF ELECTROMAGNETIC RADIATION FIELDS NEAR MICROWAVE OVENS
D.L. Solem, D.G. Remark, R.L. Moore, R.E. Crawford, H.J.L. Rechen · 1968
This 1968 government study pioneered microwave oven safety research, establishing radiation measurement protocols still used today.
Plain English Summary
This 1968 government report documented preliminary measurements of electromagnetic radiation leaking from microwave ovens, representing some of the earliest official investigation into microwave exposure from consumer appliances. The study measured radiation fields near operating microwave ovens to assess potential human exposure levels. This research helped establish early safety protocols for microwave oven manufacturing and household use.
Why This Matters
This 1968 government investigation represents a pivotal moment in EMF safety research - the first official recognition that microwave ovens could expose people to electromagnetic radiation. The timing is significant: microwave ovens were just entering American homes, and nobody yet understood the health implications of microwave leakage. The science demonstrates that even in 1968, government researchers recognized the need to measure and document microwave exposure from household appliances.
What this means for you today is profound. Modern microwave ovens still leak radiation - current safety standards allow up to 5 milliwatts per square centimeter at 2 inches from the oven door. Put simply, this 55-year-old report established the foundation for microwave safety standards we still use today, yet our understanding of biological effects has evolved dramatically since then. The reality is that what seemed 'safe' in 1968 deserves fresh scrutiny given current research on microwave biological effects.
Exposure Information
Specific exposure levels were not quantified in this study.
Study Details
To determine the levels of microwave energy to which people may be exposed if the safety devices on the ovens fail or are defeated, and to observe the response of three commercial microwave survey instruments when exposed to the microwave field emitted through the open door of an oven.
The microwave oven to be tested was placed in an anechoic chamber with the oven opening about 14 fee...
Commercially available instruments indicated power densities greater than 700 milliwatts per square ...
The Federal Communications Commission has assigned frequencies of 13.56 + 0.007, 27.12 + 0.16, 40.68 + 0.02, 915 + 25, 2450 + 50, 5800 + 75 and 22,125 + 125 Miz to devices such as microwave ovens. Four of the ovens examined in this study operated at 2450 MHz, and one operated at 915 MHz, the only frequencies currently utilized by oven manufacturers. Survey instruments used for estimating microwave power or power density levels associated with oven operation must be designed and calibrated, therefore, for at least the latter two frequencies. The observations made at NCRH on microwave ovens operating at 2450 MHz demonstrated that power density levels which measured above 700 nid / ome could be produced if the door safety devices failed or were bypassed. Under such conditions a separation of h feet between a person and the open door was often insufficient to bring the power density levels down to 10 n/on' . Tests which were performed with plastic strips in the oven door seal, a situation simlating accidental jamming or failure of sealing, revealed leakages near the door edges, some of which were 10 wiv [em or greater when measured with the instrument 5 cm from the door.
Show BibTeX
@article{report_of_preliminary_measurements_of_electromagnetic_radiation_fields_near_micr_g6813,
author = {D.L. Solem and D.G. Remark and R.L. Moore and R.E. Crawford and H.J.L. Rechen},
title = {REPORT OF PRELIMINARY MEASUREMENTS OF ELECTROMAGNETIC RADIATION FIELDS NEAR MICROWAVE OVENS},
year = {1968},
}