Laptops: hoe je te beschermen tegen de straling daarvan

woensdag, 16 oktober 2013 - Categorie: Voorlichting

Bron: .
okt. 2013

Protect yourself from laptops’ electromagnetic radiation

EMF help, info, smart meters, detection, protection, shielding

Laptops and notebooks have become powerful enough to satisfy the computing needs of most people. They have also become very affordable and consequently gained much popularity especially with the younger generation and professionals. The problem with laptops is that they expose the user to significant levels of electromagnetic radiation. Their compact structure and light weight may lead to a false belief that they are relatively EMF safe. However using a laptop actually exposes you to higher levels of electromagnetic radiation (EMR) than using a bulkier desktop computer. There are several reasons for this and it is important to get a good grasp of the concepts as this will help you apply an effective laptop EMR defensive strategy and use your laptop safely.

Laptops emit several types of electromagnetic radiation

Laptops emit several types of electromagnetic radiation. Each requires specific detection, measurement and protection measures.

Most if not all laptops are Wi-Fi enabled. What this means is that they are able to connect to a wireless local area network (WLAN) by transmitting and receiving radio frequencies (RF). At the time of writing this article the most common WLAN frequency band in use is the 2.4 GHz band (i.e. 2.4 billion cycles per second). This frequency band is part of the microwave sector of the electromagnetic spectrum. Other microwave frequency bands that are often used for WLAN networks are 3.6 GHz, 4.9 GHz, and 5 GHz microwave bands. The good news is that this problem can be eliminated completely in some cases and in other cases reduced as described below.

Laptops contain a range of internal and external components including an AC adapter, a screen, fans, a processor, a hard drive, speakers, microphone, camera and electronic circuitry. Low frequency (LF) radiation is a by-product of the alternating electric (AC) current that flows into the laptop (frequency is usually 50 or 60 Hz depending on the country you live in) and various direct currents (DC) flowing inside the laptop. These currents create low frequency (LF) electromagnetic fields that radiate into the environment causing increased electromagnetic radiation exposure. The good news is that LF radiation diminishes rapidly as you distance yourself from the source. I will discuss this in detail below.

Many of the laptops internal electronic components also generate high frequency transients that often infiltrate your home’s electrical network in the form of “dirty electricity”. The good news is that your home can be protected effectively from dirty electricity triggered by your laptop as explained below.

Here are laptop radiation causes and solutions:

Problem: If you are using your laptop with the Wi-Fi feature enabled you are being exposed to very significant levels of RF electromagnetic radiation.


If you are using your laptop to connect to the Internet get a standard Ethernet cable (also called CAT 5e RJ45) and connect your laptop directly to the router. Some Apple MAC laptops may require a special adaptor to connect the laptop to the standard Ethernet cable. Consult your Apple dealer.

Turn off the Wi-Fi functionality of the router. Some routers have a special button that enables turning the Wi-Fi off. Others may require turning the Wi-Fi off via the router’s administration software installed on your computer. Please refer to a post I wrote explaining how to turn OFF the router’s Wi-Fi functionality . Consult the user’s manual if you cannot find it.
Make sure the router’s Wi-Fi functionality stays OFF. Some routers re-enable the Wi-Fi functionality automaticlly after the router is powered off/on, after a router reset or after receiving an update via the Internet. The way to check if the Wi-Fi is on or off is to look at the router’s front panel. The WLAN led should be off. If for some reason it is on, turn the Wi-Fi off again.

You may also like to double check RF radiation levels around the router using an RF meter just to make sure the router is actually turned off. Similarly, check RF radiation levels around the laptop using the same RF meter.

Some routers can transmit on two different RF frequency bands. At times one band may be turned on and the other band turned off. To make extra sure both frequency bands are disabled you need to measure radiation levels using a wide range RF EMF meter that can measure electromagnetic frequencies of up to 5.5 GHz at least. Many RF EMF meters can only detect and measure frequencies up to 3 or 3.3 GHz (this is enough to detect most Wi-Fi routers and cell phones but not for all Wi-Fi frequency bands).

If you are planning a trip you need to prepare in advance so you can connect to the Internet safely while away. Please read the article on EMF safe travel here.

I suggest you always put your laptop on a desk and not on your lap. However if you are on the road and this is the only way for your to use your laptop you can get a laptop anti-radiation pad that will at least shield your reproductive organs from direct exposure to the laptop. However you must realize that the rest of your body will still be exposed to EMR as it radiates in all directions. As mentioned above the further you are from the source of the radiation the lower your exposure so if your laptop is sitting on your lap your reproductive organs suffer the higher levels of radiation exposure so using a laptop anti-radiation pad will reduce some of the potential harm to your reproductive organs and to your future offspring.
Note: If you are travelling or in a public library or cafe and have no other alternative but to connect your laptop to the WLAN via Wi-Fi make sure the reception is good. You can tell by the number of bars on the Wi-Fi icon on the screen. Do not connect if the reception is poor as in some cases this may result in higher radiation levels being emitted from the laptop’s Wi-Fi.

Problem: Laptops emit significant levels of low frequency (LF) radiation. There are several sources of LF radiation associated with laptops. These include the laptops AC Adapter/power supply, the screen, the fans, and circuitry. Unlike RF radiation most sources of LF radiation in the laptop cannot be turned off. However there are steps that you can take to significantly reduce your level of LF electromagnetic radiation exposure. Each of these requires specific attention and protection.


Problem source: Most laptops are connected to the electric socket via an external AC adapter that usually looks like a little black box (or little white box in some MAC Apple laptops and notebooks). These adapters all emit significant LF radiation. If they are old and/or slightly defective they may emit very high LF radiation.

Solution: Take the following steps to protect yourself:
Step no. 1: Measure LF radiation levels close to the AC adapter using an LF EMF meter. The magnetic field directly next to the adapter should not exceed 2-3 milligauss. If it exceeds 3 milligauss you may consider testing similar adapters and perhaps getting a new adapter.
Step no. 2: Move the AC adapter as far away from you as possible. It usually comes with a long cord that will allow distancing it at least one meter away. Then re-test LF radiation levels close to your body to make sure they have dropped considerably. Hopefully readings close to your body will be similar to the general ambient levels of magnetic EMR in the room.

Problem source: The internal components of the laptop emit LF electromagnetic radiation. Your hands are positioned directly on the keyboard and exposed to a high level of LF EMR. Even if you are not worried about your hands you should be because radiation exposure affects the nerves running through your fingers and the blood supply. Since the blood circulates throughout the body, exposing the fingers to EMR will eventually affect every blood cell in your body.

Step no. 1: Measure radiation levels using an LF EMF meter. Disconnect the laptop from the AC power and use it on battery power. This may reduce levels of LF EMR.
Step no. 2: Measure radiation levels again using an LF EMF meter. If they are still too high get an external wired mouse, wired keyboard and perhaps also an external LCD display screen. The external display, mouse and and keyboard should be equipped with sufficiently long cables. Connect the keyboard, mouse and display to the laptop. Position them in front of you on the desk. Position the laptop as far from you on the desk as the cables allow. Position the AC adapter as far from you as its cable allow. Re-test EMR levels . Hopefully they will be much closer to the general ambient level of EMR in the room.

Problem source: Some laptops are not grounded. In other words the power cord connecting the laptop to the AC adaptor only has two pins and two wires and not three electric pins and three wires as in grounded laptops. Laptops that are not grounded emit higher levels of EMR than grounded laptops.

Step no. 1: Apply the same procedure and solutions described above. In other words, test radiation levels, connect the laptop to an external wired keyboard, mouse and LCD screen and position the laptop itself as far away from you as the keyboard and external display screen cords allow.
Step no. 2: If radiation levels around your body are still higher than ambient levels you may use the following additional measure. Get a universal earthing mat . Connect it following manufacturer’s instruction and position it on your desk as far away from you as cord length allows. Position the laptop on top of the mat. Re-test radiation levels. Whether or not this helps depends on your laptop’s configuration. This is only an additional measure and not a substiture for using external keyboard, mouse and screen.

Problem source: The laptop’s external AC adapter and/or laptop itself may be inducing an AC voltage in your whole body.
solution: Get a universal earthing mat connect it according to manufacturer’s instructions. Position it on the floor under your feet. Take off your shoes and socks and have your bare feet firmly on the mat. This will earth your body and reduce levels of AC voltage on your body.
Problem source: The laptop’s electronic components may be generating high frequency transients that leak back into the electrical network and create dirty electricity throughout your home’s electrical network.

Step no. 1: Get an extension cord with a multi-socket and plug it into the AC socket you intend to use for the laptop.
Step no. 2: Get a Graham Stetzer dirty electricity meter. Measure the level of dirty electricity (in GS – Graham Stetzer units). It should be lower than 50 GS units.
Step no. 3: Plug the laptop into the multi-socket and remeasure using the Graham Stetzer dirty electricity meter. A significantly higher reading than before indicates the laptop is polluting your electrical network with dirty electricity.

As you can see using a laptop computer exposes you to significant levels of electromagnetic radiation but by applying the simple steps above you can dramatically reduce your exposure and stay EMF safe.

For adaptor see: .

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