ElectromagneticFields

Living with your laptop

Written by Karen Kingston Sunday, 06 December 2009 00:14

Laptops with LCD or TFT screens emit much lower electromagnetic fields (EMFs) than regular computers and are much easier on the eyes too (less flicker). However this is only the case while the laptop is running on battery. As soon as you plug it into the mains, the electric field of most laptops soars. I've taken readings as high as 800 volts per meter (V/m) on some laptops, and it's rare to get readings of less than a few hundred V/m.

So always check the EMFs of a new laptop before you buy one (see my recommendations about how to do this) and NEVER put a laptop on your lap while it’s running on mains power. If you're electrically sensitive, having one on your lap even when it's being run on batteries is not pleasant either, and some models can get hot enough to burn you (story about a Swedish scientist who burnt his genitals).

Laptop earthing leads
Sometimes the problem is not the laptop itself but the wiring system it is plugged into. In one office I used to work in, the electric field of my laptop was 460 V/m. The same laptop, when plugged in at home, measured only 5 V/m. That's a huge difference! Working in such a high electric field day after day my hands, arms and neck got progressively stiffer, my vision fuzzier and my perception woozier. It was difficult to complete any task and by the end of each day I was exhausted. Something had to be done.

I got an electrician in to check the earthing of the building and he managed to get the electric field down to 330 V/m, but it was only when I attached an earthing lead to the back of my laptop and plugged it into a mains socket that the field reduced down to the tolerable level of 9 V/m. Not as good as the 5 V/m I get at home but infinitely preferable to the zapping I was enduring before. Now I always take an earthing lead with me wherever I go in the world. It's small, lightweight and because of the amount of time I spend using my laptop, absolutely essential.

Why laptops need earthing leads
The reason why an earthing lead is needed at all is because most laptops have a 2-wire mains lead. Manufacturers say that this is to protect against electric shocks but when I talked to Alaisdair Philips at Powerwatch about this years ago he told me he believes it is mostly done this way because it's a cheaper option. If they choose to, all manufacturers could make a very simple modification to reduce the electric fields of the laptops they sell down to almost zero but if you get an electrical engineer who knows about this to do it for you, it makes the manufacturer’s warranty invalid.

Actually, a few years ago, after a purchaser threatened to take Dell to court over electrosensitivity damage to her daughter, the company started to supply their Inspiron range in the UK with a properly earthed power supply. But this only lasted for about two years and they now seem to have gone back to the two-wired non-earthed supply again. Once I bought a top end IBM laptop myself simply because it had this feature built in, but it was double the price and not really worth it. That was before I discovered earthing leads, which Alaisdair taught me how to make myself, and now sells ready-made at www.emfields.org/screening/overview.asp.

A lead currently costs £7.00 when fitted with a UK plug or £5.00 if you fit your own plug (European, US, etc). If you have a new kind of laptop that doesn’t have any exposed metal parts at the back to clip the earthing lead's crocodile clip to, then you will also need to buy a Belkin USB extension cable, price £4.40 (it must be Belkin because other types of extension leads are not suitable). Yes, there is postage to pay on top of these prices but even so, it’s a very cheap and viable solution. Leads can be ordered online if you live in the UK, or call +44 1353 778814 for overseas ordering. Those of you who live outside the UK may be able to find earthing leads from other sources, get a local electrics or electronics technician to make one up for you, or even make one yourself (but only if you understand electrical safety issues!).

Wired keyboards & mice
A few years ago, when external keyboards and mice had the round PS2 connectors rather than USB and were a lot less sophisticated that the ones you can buy today, plugging them in to your laptop and using them rather than the laptop’s keyboard or mousepad would significantly reduce your electromagnetic field exposure. The new USB keyboards and mice still do this to some extent where the magnetic field is concerned, but I haven't found they do anything at all to reduce the electric field level. I don’t know why this has changed over the years, but it has. The only solution, therefore, is to fit an earthing lead to the entire laptop, which reduces the electric field of the keyboard and mouse too.

The best way to tell if you need a laptop earthing lead is to use an accurate EMF meter that can measure electric fields as well as magnetic fields. The EMFields Pro Meter and the much cheaper Gigahertz Solutions 3030B meter will both do this, and if you mention my name the retailer, Sensory Perspective, will give you a 10% discount.

Wireless keyboards and mice
Wireless keyboards and mice do not expose you to electric fields but they operate on radiofrequency microwaves which pose health hazards of their own so are definitely not recommended. Infrared seems to be fine.

Alasdair Philips advises: "Almost all new laptops come with BOTH WiFi and Bluetooth built-in and set to "active" as the default. Both should be switched off and each needs to be done separately. There are many reports of adverse effects of WiFi on wellbeing and you should always use a plugged-in wired Ethernet connection. If you need to use the laptop in different rooms in your house, you can connect the signal from your router/modem using a pair (or more) of dLANS that send the signals along the mains wiring. They do use low-frequency RF but at very low power levels and virtually none radiates into the room. Even so, they should all be switched off at night when you go to bed."

Posture
This has nothing to do with EMFs but if you habitually use a laptop, I recommend putting it on a stand so that you can look straight ahead at the screen when working at it instead of having to tilt your head down. If you don't have a custom-built stand, use an upturned box or a pile of large books.

Personally I also work at a low table sitting cross-legged rather than sitting in a chair. This makes for even better posture and much less back strain (the standard design of a western chair is one of the most stressful postures there is for a human back). An alternative to this is to get yourself a wide padded bench seat so that you can sit cross-legged at regular desk height and put your legs down any time they get tired. Whatever you do, make sure your posture is as vertical as possible when working at a laptop or computer.

Laptop screens
Laptops with non-reflective screens are best. Many are now coming with highly reflective screens that are difficult to use in daylight or in rooms with lights behind you. The reflections also cause near/far focussing problems for your eyes because the screen image and the reflections are located in different places. About ten years ago there were strong recommendations that screens should be non-reflective. It's not clear why this good advice is now being ignored. It feels to me like a fashion thing. The glossy screens look more glamorous, but at what cost to your eyesight?

Many thanks to Alasdair Philips who kindly checked the content of this article for accuracy and added some information of his own. Alasdair is qualified in both Electrical and Electronic Engineering and in Agricultural Engineering. Since 1986 he has built up a considerable knowledge of EMF bioeffects, and is one of the leading 'alternative' voices on the subject in the UK. He is also a member of SAGE (the UK Department of Health Stakeholder Group on ELF EMFs), a member of the UK Health Protection Agency's EMF Discussion Group, and one of the main contributors to the Powerwatch website, which I have found to be one of the most reputable and reliable sources of EMF information available today.