eco living - electromagnetic fields

Electromagnetic fields (emf's) are invisible fields that most of us don’t pay much attention to.

They are generated by power lines outside our homes (overhead and underground), communications equipment, household wiring, lighting and appliances.

These sources generate both electric and magnetic fields. There have been many international studies on both types of fields, however mostly there are concerns about the effect of magnetic fields.

Most research agrees that the risks are from cumulative exposure to high voltage current, which is why people are wary about living close to electricity substations, power pylons or electrical transformers. DC currents – as from batteries make fields but these hardly affect us in the same way.

Whilst we might feel unconcerned about emf's (because we don't live under power pylons), we should be concerned about exposure from emf's in our own home.

British epidemiologist, Sir Richard Doll (who established the link between smoking and lung cancer) produced a report based on number of different studies of children living in high fields from domestic appliances. The report concluded that 'exposure to 04uT was associated with a doubling of the risk of leukaemia before age 15 from about one in 1,400 to one in 700'. (http://www.100megsfree4.com - originally published by The Guardian/London, by James Meek - March 7 2001).

This is a level of exposure equivalent to 4 milligauss which many people are exposed to in their homes, often as a result of hazards which are avoidable.

In 2001, The International Agency for Research on Cancer, concluded that 'ELF* magnetic fields are possibly carcinogenic to humans, based on consistent statistical associations of high level residential magnetic fields with a doubling of risk of childhood leukaemia' (http://www.iarc.fr).

*ELF = extra low frequency ie 50Hz mains power supply.

Therefore it is important, especially where small children are concerned to reduce the exposure to emf’s within your home.

The first thing to remember is keep a distance between your child and household appliances as fields from any source drop off rapidly with distance. One metre is usually OK in the house, but 1.5m is recommended from the TV and powerful speakers.

Also remember that the amount of exposure you receive depends on how much time you spend in a field. So limit the time your children spend in front of the television, computer or playstation. When the children do these activities, get them to take regular breaks and play outside and absorb some fresh air instead.

Avoidable electromagnetic hazards:

High voltage power lines:

How do you recognise them?

In New Zealand, the 230V 3 phase local distribution cables are in threes. These cables are sometimes referred to as 440V.

The 11,000V cables are the urban distributors that run along the street margins and supply the street transformers. There are sometimes two cables (or three cables in case of three phase). Cables are thicker than the 230V. Street transformers may be a box at the side of a street or mounted on the pole.

If you have either of these power lines and/or transformers outside your home, use the rooms towards the back of the house ie away from the street as bedrooms. Allow 6m from 230V cables, 10 metres from 11000V cables.

The overland links are usually 150,000 and 250,000V ie 150KV and 250KV and up to 500KV. In USA voltages vary from 110KV to 765KV. These are usually in two sets of three called a “delta” and are recognised by the size of the hanging insulators, which are huge. They are usually on steel pylons although concrete is now being used for 150 KV overland links. Research used to say that 100m would be a safe distance from these but recent research suggests this is not enough.

These grid power cables do not run underground because of the cost of insulating them.

The following are things are simple things you should do to reduce emf exposure for your family inside your home:

In the nursery:

• Move the baby’s nightlight or bedside light well away from the cot/bed.
• Avoid baby monitors.
• Move bedside cupboards away from the cot/bed. Bedside cupboards can conduct electrical emf's if they are touching the cot/bed.
• Check the cot/bed is not located above a metal water pipe that is conducting a high field. Iron and copper pipes can conduct power leakage and thus create magnetic field.
• Beware of power cables across under the floor of a bedroom or lounge. A fridge supply can keep cutting through the night and produce surges.
• Beware of garage door openers are often the garage ceiling and may be under the floor of a bedroom.
• Check what's on the other side of the nursery wall. Especially beware of computers, cellphones, digital alarm clocks and electric toothbrush chargers.
• Extension cables should never be pushed under the bed. Keep them away from legs of furniture .
• Don't put a baby on a water bed or electric blanket.

In the kitchen:

• Place your microwave away from the main working area of the kitchen - even better in the laundry or garage. It emits the strongest emf's in your kitchen. Even when it is not operating it emits a field up to 0.5m (1.5m when running).
• Never operate your microwave around baby.
• Do not stand in front of the oven, microwave, dishwasher etc with baby when they are running (an oven clock as well as the oven will emit a field up to 50 cm).
• Operate the dishwasher at night when baby is asleep.

Around the house:

• Keep children at least 1.5 metres from the television screen.
• Avoid speakers close to the lounge suite where they can charge up the coil springs or framing.
• For the same reason, do not run cables under your lounge suite.
• Do not trail electric cords including vacuum cleaners across the path of a crawling baby. Vacuum when baby is in bed!

Cellphones and digital cordless:

The signals from this type of equipment, in the 1 – 10 GigaHerz range, vibrate the living cell and the DNA causing faults in mitosis. If you must use it, make sure it is more than 2m from your baby.

Keep all cellphones away from sleeping areas. Remember to alert guests to this rule.

Cellphone transmitter towers should be shunned by at least 50m.

Tell everyone:

• Make your partner/caregiver/nanny aware of these guidelines.
• Tell guests and visitors to the house - especially about cellphones.