Report on the Safety from Electromagnetic Radiation in and Around the CN Tower
Authors not listed · 1977
Canada's 1977 CN Tower radiation safety assessment shows early government recognition of EMF exposure risks from major broadcast infrastructure.
Plain English Summary
In 1977, Health and Welfare Canada conducted a safety assessment of electromagnetic radiation exposure levels in and around Toronto's CN Tower, which was then the world's tallest structure. This government report evaluated potential health risks from the tower's broadcast antennas and transmission equipment. The study represents an early official examination of EMF exposure from major broadcasting infrastructure in urban environments.
Why This Matters
This 1977 government assessment of CN Tower radiation exposure offers a fascinating glimpse into early official recognition of EMF health concerns from broadcast infrastructure. What makes this particularly relevant today is that the CN Tower housed multiple high-power television and radio transmitters in a densely populated urban area, creating exposure scenarios similar to what we now see with cell tower deployments in cities worldwide. The reality is that broadcast towers like the CN Tower can generate significant electromagnetic fields extending well beyond their immediate vicinity, potentially affecting thousands of residents and workers. While we don't have the specific findings from this report, its very existence demonstrates that government health agencies were taking EMF exposure seriously nearly five decades ago. Today's cell towers operate at different frequencies but often at much closer distances to homes and schools, making historical assessments like this one valuable benchmarks for understanding how official attitudes toward broadcast radiation have evolved.
Figures from the Original Paper
Diagram extracted from the original research document.
Exposure Information
Specific exposure levels were not quantified in this study.
Study Details
To assess any possible health hazards to the general public and employees working within the CN Tower from electromagnetic radiation emissions
Field intensity measurements were taken at all levels of occupancy within the CN Tower, on the roofs...
Measurements were recorded in db(uV) and converted to watts per square centimetre by taking into acc...
From the results of this survey and the data gathered during 'other surveys', it appears that within and around the CN Tower and in buildings in downtown Toronto normally occupied by the public, microwave radiation levels were well within permissible limits. Within the CN Tower, at locations generally occupied by workers and not normally frequented by the public, microwave radiation levels were also found to be well within the permissible limits. Measurements taken at generally inaccessible locations around the antenna feed dividers and near the vibration dampers, were significantly higher. However, when one accounts for the occupancy of the areas, the microwave radiation levels were within the recommended exposure limits for microwave radiation workers. At the time of the survey all equipment had not been installed at the CN Tower, and some broadcasting stations had not been operating at their fully licenced power levels. However, based on the data gathered during the survey, it is expected that the power density levels in all accessible areas will still be within the recommended limits. There does not appear to be a health hazard to either the microwave radiation workers or the general public from the electromagnetic transmissions of the CN Tower.
Show BibTeX
@article{report_on_the_safety_from_electromagnetic_radiation_in_and_around_the_cn_tower_g7315,
author = {Unknown},
title = {Report on the Safety from Electromagnetic Radiation in and Around the CN Tower},
year = {1977},
}