See Also: Electric Field
Related to the Currents in the line, the primary cause of induction to long objects, such as fences
and pipelines (see Specifications - Piping). A magnetic field’s strength is determined by the amount of current flowing through a wire (see Conductor). Strange as it may seem, the magnetic field around a 161,000-Volt transmission line carrying 100 Amperes can be the same as the field around a 120-volt line carrying 100 amperes.
For example, a common, hand-held hair dryer emits a surprisingly high magnetic
field because its fan and maximum Heat setting pull significant amperage. Magnetic fields are measured in
milligauss (see Gauss, Carl Friedrich). Unlike electric fields, however, magnetic fields cannot be blocked, but
their intensity decreases dramatically as you move away from the source. Because
magnetic fields cannot be blocked, even by the ground, burying overhead lines
to lower fields for supposed health reasons would not help.