Distance for field to fall to various values

The usual way of expressing the field from a power line is to show how the field falls with distance. Sometimes it is more helpful to express the distance for the field to fall to a certain value of field. This table presents this information.

* typical fields from this line do not reach this value anywhere

"Corridors" round power lines

The UK does not have any restrictions on how close power lines and homes can be to each other, but "corriidors" are sometimes proposed.  The width of these corridors is sometimes derived from the distance for the field to fall to a particular value - see more details.

Other countries

A report from the Netherlands* calculated the equivalent distance for fields from overhead lines at 50 kV up to 380 kV to fall the various values.  (These distances were calculated as the single distance from all power lines that included the same number of homes as the actual number of homes exposed at the given level - this is a way of averaging over lines where the range of the fields is greater or lesser.)

* Kelfkens et al, Costs and benefits of the reduction of magnetic fields due to overhead power lines