Overhead transmission line located near an educational institution
Overhead transmission line located near an educational institution
An existing overhead transmission line (120 to 315 kV) runs close to a school building in a residential neighborhood in Ontario, Canada. The center of the power line is approximately 100 feet (30 meters) from the building. Measurements taken near the structure indicated a potential for exceeding recommended levels based on guidelines in other countries. In other countries at similar distances, values have been recorded that exceed limits set by strict regulations for educational institutions. In sensitive places such as schools, it is recommended to aim for the lowest possible exposure levels. In many cases, simple mitigation measures can be applied, such as relocating classrooms or installing an active shielding system, without the need to bury or move the power lines.
Magnetic Field Levels Measured at Various Distances from the Line Center (End of November)
At a distance of 0 m beneath the centerline of the transmission line, a magnetic field level of 17 milligauss was measured.
At 5 m, the measured field was 14 milligauss.
At 10 m, the measured field was 10.7 milligauss.
At 15 m, the measured field was 8 milligauss.
At 20 m, the measured field was 6.2 milligauss.
