Magnetic Fields and Electrical Appliances
High current devices, appliances and machinery will by definition create high magnetic fields. When an appliance is turned on, there will be a powerline magnetic field, due to current, which can be measured by an AC gaussmeter in the unit of the milligauss or microTesla.
Key scientific reports and statements on magnetic fields suggest a safety level of 1 milligauss. This stands in stark contrast to much higher official standards of 833 mG at 60 Hz, which are not sufficiently protective of public health.
The following provides a partial list of appliances (point sources) typically found in a household. The first half of the list indicates appliances that can produce high intensity magnetic fields but because they are on for a relatively short time pose less of a threat than appliances that are on more or less continuously.
High fields, short use:
- Electric kettles
- Electric can openers
- Electric stoves, ovens, hubs
Moderate to high intensity fields, long term use:
- Electric blankets
- Electric ‘blow’ heaters
- Digital alarm clocks
Appliances and Safety Distance
Anything that runs electricity, including all electrical appliances are sources of magnetic fields. However, for most point sources, the strength decreases quickly with the square of the distance (see Distance Matters). After 1 meter from typical appliances, levels are generally within limits thought to be acceptable, but conversely, levels within 1 foot of the source could be high. Coils can also generate huge magnetic fields which decrease with the cube of the distance. For most household appliances, observing a 1 meter distance is usually good enough for ELF safety concerns, since the strength of the field decreases quickly with distance from the source. To give you a general feel for EMF levels of typical appliances, an alarm clock or radio measures about ~50 mG (milligauss) directly at the source, ~2 mG at 1 foot, and ~0.6 mG at 2 feet.