- All electric appliances connected to the mains will give off electric and magnetic fields (EMFs) in use. When plugged in, they will give off an electric field, even when switched off at the appliance.
- Electric fields are measured in volts per metre (V/m).
- Electric fields rise towards ceilings and light switches. Sockets give off electric fields unless metal-clad and unless the wires are in metal conduit.
- Walls which may be slightly damp can become conductive. They can then pick up an electric field and re-radiate it over a large area.
- Appliances that are unearthed, i.e. only having a 2-core cable, will give off high electric fields.
- The NRPB suggests that the average field level in the centre of a room in a modern house is about 10 V/m. We have found that fields are often considerably
higher than this.
- High electric fields increase the risk of developing illness, especially when combined with magnetic field exposure. Most people who suffer from electrical hypersensitivity (EHS), are particularly sensitive to electric fields. It seems that damage from EMFs can be both instantaneous and cumulative.
- International research has linked magnetic field exposure with cancer, especially childhood leukaemia and breast cancer, depression, some forms of dementia and immune system dysfunction. Some drugs such as the anti-cancer drug Tamoxifen are less effective when exposed to EMFs. High levels can reverse the effect, reportedly making Tamoxifen a possible cancer promoting drug.
- Magnetic fields are generally measured in units of magnetic flux called microtesla (µT) in the UK and milligauss in America.
- In living areas, magnetic fields should be below 0.15 µT, in bedrooms below 0.10 µT, and in other areas of the house (and garden) a maximum of 0.20 µT. The average field level in the centre of a room in a modern house is about 0.04-0.05 µT. It is important to minimise EMFs where you sleep and where you spend long periods of time sitting. Check the electric and magnetic field levels of clock radios, bedside lights, TVs, computer monitors (especially the side and back in offices), fluorescent and halogen lights, cars, washing machines and cookers (especially when pregnant), hairdryers, etc.
- There are a significant number of houses where large magnetic fields are produced by unseen and un-noticed wiring faults. See wiring factsheet.
- Field levels can vary significantly over a 24-hour period. In cold weather, they can be up to three times higher than hot weather, because of the extra demand for electrical heating.
- Many appliances in offices (photocopiers, computers and monitors, faxes, etc), and other workplaces (hospitals, schools increasingly, traditional and complementary health centres), and manufacturing environments, give off varying, sometimes high, levels of EMFs.
- The hormone melatonin helps the body repair cellular damage. It is produced by the pineal gland in the brain mainly at night, the pineal gland being "switched on" by dark conditions. EMFs reduce the effectiveness of melatonin. It is low in people suffering from clinical depression.
- Some appliances also give off microwave radiation. Microwave exposure has been linked to sleep disorders, headaches, heart arrythmias, epilepsy, blood pressure changes, concentration and memory problems, behavioural and mood disorders.
- Check the microwave field levels of cordless phones, walkabout baby monitors, microwave ovens, meter cupboards where the meter can be remotely read, cars, networked computers, laptops, game consoles, etc.
- Children are more susceptible to EMFs because their cells are multiplying much more rapidly as they grow and are therefore more prone to damage from microwave sources inside or outside the home.
If you are concerned about electromagnetic fields from electrical appliances within your home, our "Electrical Appliances" article in our article library looks at over 100 common household appliances and their associated field levels.