8,700 Studies Reviewed. 87.0% Found Biological Effects. The Evidence is Clear.
Shield Your Body
Whole Body / General

Nonionizing Radiation Levels in the Washington, D.C., Area

Bioeffects Seen

Stephen W. Smith, David G. Brown · 1973

Share:

Urban EMF levels measured in 1969 were 30 dB below safety guidelines then, but today's wireless world creates vastly higher exposures.

Plain English Summary

Summary written for general audiences

Researchers measured radio frequency and microwave radiation levels across 10 locations in the Washington D.C. area in 1969, covering frequencies from 20 Hz to 10 GHz. The highest levels found were approximately 10⁻² μW/cm², primarily from commercial sources, which were 30 decibels below U.S. occupational exposure recommendations at the time.

Why This Matters

This 1973 study provides a fascinating historical snapshot of urban EMF exposure levels from over 50 years ago. The reality is that radiation levels have increased dramatically since then. The highest power density they measured (10⁻² μW/cm²) would be considered relatively low by today's standards in many urban environments. What this means for you is that we're living in a fundamentally different electromagnetic environment than previous generations. The science demonstrates that our daily exposure to radio frequencies has increased exponentially with the proliferation of cell towers, WiFi networks, and wireless devices that didn't exist in 1969. While these 1969 levels fell well below occupational guidelines of that era, today's cumulative exposure from multiple sources presents a more complex picture that warrants careful consideration.

Exposure Information

Specific exposure levels were not quantified in this study.

Cite This Study
Stephen W. Smith, David G. Brown (1973). Nonionizing Radiation Levels in the Washington, D.C., Area.
Show BibTeX
@article{nonionizing_radiation_levels_in_the_washington_d_c_area_g6897,
  author = {Stephen W. Smith and David G. Brown},
  title = {Nonionizing Radiation Levels in the Washington, D.C., Area},
  year = {1973},
  
  
}

Quick Questions About This Study

The study measured electromagnetic radiation across a broad spectrum from 20 Hz to 10 GHz, covering everything from extremely low frequencies to microwave ranges used by various commercial and communication sources in the urban environment.
Researchers estimated their measurement accuracy at ±10 dB, which represents a reasonable margin of error for the radiation detection equipment available in 1969. This level of precision was adequate for identifying general exposure patterns.
Commercial sources generated the highest radiation levels at almost all measurement sites. This likely included radio and television broadcasting stations, early microwave communication systems, and other commercial electromagnetic installations operating in the area.
The highest measured levels (10⁻² μW/cm²) fell 30 decibels below published U.S. occupational exposure recommendations of that time period, indicating a substantial safety margin according to the standards then in effect.
Researchers monitored radiation levels at 10 different sites within a 25-mile radius of Washington D.C. during summer 1969, providing a representative sample of urban electromagnetic exposure patterns across the metropolitan area.