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Medical Evaluation of Man Working in AC Electric Fields

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W. B. Kouwenhoven, O. R. Langworthy, M. L. Singewald, G. G. Knickerbocker · 1967

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Power line workers exposed to extreme 60 Hz electric fields showed measurable physiological changes over 32 months of monitoring.

Plain English Summary

Summary written for general audiences

This 1967 Johns Hopkins study tracked 11 power line workers exposed to high-voltage 60 Hz electric fields over 32 months, comparing health effects between conventional workers using insulated tools versus those working barehanded from aerial buckets connected to live wires. The research examined physiological impacts of occupational AC electric field exposure and evaluated protective equipment effectiveness.

Why This Matters

This study represents one of the earliest systematic attempts to document health effects in workers exposed to power frequency electric fields. What makes this research particularly significant is its focus on extreme occupational exposures - these linemen experienced field strengths thousands of times higher than typical household levels. The 32-month monitoring period provided valuable longitudinal data on sustained exposure effects, something often missing from modern EMF research. The comparison between conventional safety methods and direct contact techniques offers insight into dose-response relationships. While the study predates our current understanding of EMF bioeffects, it established important precedents for occupational safety standards and highlighted the need for protective measures in high-exposure work environments.

Exposure Information

Specific exposure levels were not quantified in this study.

Cite This Study
W. B. Kouwenhoven, O. R. Langworthy, M. L. Singewald, G. G. Knickerbocker (1967). Medical Evaluation of Man Working in AC Electric Fields.
Show BibTeX
@article{medical_evaluation_of_man_working_in_ac_electric_fields_g6104,
  author = {W. B. Kouwenhoven and O. R. Langworthy and M. L. Singewald and G. G. Knickerbocker},
  title = {Medical Evaluation of Man Working in AC Electric Fields},
  year = {1967},
  
  
}

Quick Questions About This Study

Power line workers can be exposed to electric field strengths thousands of times higher than typical household levels, particularly when working on energized high-voltage transmission lines using direct contact methods from aerial buckets.
The Johns Hopkins researchers conducted physiological examinations on the 11 linemen over a 32-month period, providing one of the longer-term occupational EMF exposure studies of its era.
Hot stick methods use insulated tools to maintain distance from live wires, while barehanded technique involves workers in aerial buckets making direct contact with energized conductors, creating much higher EMF exposure levels.
Yes, this 1967 study specifically examined how Faraday screens provide protection for workers in high-voltage AC electric fields, contributing to early understanding of occupational safety equipment effectiveness.
60 Hz is the standard power line frequency in North America, making it the primary occupational EMF exposure for electrical utility workers maintaining and repairing high-voltage transmission infrastructure.