Safer Use of Computers
To view information on Netgear Network Extenders that use electric circuits to carry Internet from your router to other rooms in your house so that you can avoid Wi-Fi, click here.
Page last updated April 11, 2014.
There are four main kinds of EMFs, and you will potentially find all four at a computer work station. These are magnetic fields, electric fields, Wi-Fi, and so-called "dirty electricity." These are each discussed separately below.
The most harmful type of EMF at computers, although it is fast becoming the least common, is magnetic field exposure from the old cathode ray tube style of monitor, which is really a TV set. We would never sit as close to a television set as we do in front of a computer monitor. The field can extend three to four feet in all directions, even through a wall into another room.
This is rapidly becoming a non-issue with the use of flat screen monitors and laptops, both of which use LCD, or Liquid Crystal Display, technology or even newer LED, or Light Emitting Diodes to light up the screen. Neither LCD nor LED monitors emit magnetic fields beyond a couple of inches from the base.
If you still own a cathode-ray tube monitor, the best solution is to replace it with a flat screen stand-alone monitor or a laptop as soon as possible. They are much more affordable now than initially. If you are still really sensitive to even a flatscreen monitor or laptop, then purchase a remote keyboard and move the flat screen monitor or laptop further away. Find the setting in the Control Panel to change the pixel size on the screen (usually under "Display," and then click on the tab labeled, "Settings"). This way you can increase the size of the icons and font on your screen to see them from farther away. You can also purchase radiation screens and anti-static shields from Less EMF (remember you need to ground the shield).
There are also magnetic fields around every transformer that you have plugged into the power strip. The field extends out about 1-2 feet. The solution is to move the power strip away from your feet by at least three or four feet. A little distance makes a big difference.
There are also small magnetic fields produced from the motor of the hard drive inside the computers, but that is relatively small. Still, you should move a computer tower away from your knees by a few feet rather than having it right against your knee. Ideally move it outside the desk to the side as far away from you as possible. Once you move the computer, purchase extension data cables from Radio Shack, Frye's or Best Buy if your existing data cables do not reach between the computer and your keyboard, monitor and peripheral equipment.
Finally, if you have a laptop computer, there will be a magnetic field around the in-line transformer. Just move it as far away as the cord will allow and you should be fine.
You can reduce electric field levels at your computer workstation by replacing the electric power cords of most desktop computers, monitors and some printers with a shielded AC power cord available at Radio Shack for $10. If the existing power cord pulls out from the back of your computer, monitor or printer, take it to Radio Shack and show it to the clerk. Ask for the AC Shielded Power Cord, Part # 61-206, to replace it. Use that shielded power cord instead of the cord that came with the computer (unless you already have a shielded power cord, indicated by the word "SHIELDED" mixed in with the lettering imprinted on the cord itself, which is very rare).
Replacing the AC power cord with a shielded cord is not possible with most inline transformers, unless you have one that has a detachable AC power cord that has a plug on the appliance end that matches the shielded AC power cord from Radio Shack.
Laptop computers can also be sources of high electric field exposure while they are plugged in if they are ungrounded. (This is not a problem with desktop computers because they are already grounded through a three-pronged plug, but you must make sure the outlet has a properly working ground--see below.)
Many PC laptops have a two-pronged, ungrounded plug on the end of the cord, and Mac laptop power cords can be configured in such a way that they, too, are ungrounded.
When the power cord plug is ungrounded, placing your hands on the keyboard can produce significantly high electric field exposure, even if you don't touch the case, and even if the case is plastic and not metal. This is particularly a problem if you spend hours each day on an ungrounded laptop computer, like several clients of mine who complain of marked fatigue and agitation when doing so.
If the AC power cord is already grounded (three-pronged), then the laptop will be grounded and there will be no problem. When the plug has only two prongs, however, then the laptop will be ungrounded.
If the laptop's power supply is not already grounded, there are several workarounds:
You will notice an immediate reduction in fatigue when you make sure that your laptop is properly grounded. Now, instead of seeing 5,000 milliVolts (mV) or higher of electric field exposure on the body voltage test when you touch the keyboard, as I have seen with many clients with ungrounded computers, the level drops down to a healthy 100-200 mV. That is the range, or close to it, that you want to see.
If the electric field level drops but not as low as 100-200 mV, what remains would be coming from having your legs close to plastic-jacketed AC power cords for a lamp and other appliances at your desk (paper shredder, printer, etc.), as well as plastic-jacketed "Romex" circuits in the walls, but at least you won't be tired all the time when you use your laptop. You can reduce these remaining electric field levels by moving all 120 Volt plastic AC power cords as far away from your legs as possible, preferably 3-4 feet. Distance does make a difference. The low voltage cords generally do not cause a problem.
You also have a problem when the computer plug is grounded but the outlet is an older ungrounded two-pronged outlet and you are using a three-to-two, so-called "cheater plug" in order to power your computer. Or, the outlet does have a third hole but a circuit tester shows that the ground is non-functional.
If either of these conditions are the case, call an electrician to provide you with a properly grounded outlet where you use your computer. While waiting for that repair, run a grounded (three-pronged) extension cord to your desk that is plugged into an outlet that is properly grounded, and verify that by plugging your circuit tester into the extension cord.
You can also have a surge protector or power strip with a non-working ground. I have seen that. Verify this with your tester and if the surge protector/power strip is not grounded but the outlet is, you must replace it.
Reducing Electric Fields at Computers with Grounding and "Earthing" Pads
The discussion above has relavence to a topic that is on many people's minds these days, and that is, grounding or "earthing" pads for your bed and computer work station. If you have high electric fields at your computer, some advocate that you simply put your feet on a grounded earthing pad.
While a body voltage meter will show a reduction in electric field exposure when you do this, the German building biologists found that you are in fact passing man-made micro-current and micro-voltages through your body to the earth. This is not healthy. We believe you are better off grounding an ungrounded computer first and foremost using one of the options given above and then using an earthing pad for all of its benefits, rather than just solving the problem by using an earthing pad alone. You will be better off in my opinion if you do both.
Just be sure to move any 120 Volt AC power cords as far away from your legs as possible. These include the power cords for lamps, paper shredders, sound systems, batter back-ups, and anything else at your feet under or near your desk. Move these cords at least 3-4 feet away, if you can.
I discuss earthing pads in more detail in my "Position Paper on the Proper Use of Earthing and Grounding Pads to Combat Elevated Electric Fields.
Wired Versus Wireless (Wi-Fi) Routers and Local Area Networks (LANs)
The most significant EMF at computer work stations today is wireless frequencies. Your network to the world wide web can either be hardwired, as it was in the "old days," or wirelessly between your computer and an Internet router. You can also connect to other computers and your printer through wireless, also known as Wi-Fi.
Wi-Fi networks are in fact being used for many more purposes today, allowing you to connect your smart cell phone, camera and even appliances and your electric meter with your computers and with each other. The plan is to eventually have a total grid within and between homes securely sharing information. The problem is, research shows this to be detrimental and many have fallen ill as a result of exposure to these technologies.
Our goal is to show you how high speed Internet service can get to multiple computers in your house on the same Internet account without using Wi-Fi. We recommend that you set up a hardwired network or local area network (LAN). It doesn't matter how the data stream gets into the home (DSL from phone lines, now FIOS and U-Verse, or from the cable company or satellite). There is no problem with that from an EMF standpoint. The radio frequency EMFs come from the use of a router to connect computers and printers in a house in a wireless network. You want to connect these devices in your house through a hardwired network.
That is accomplished by ideally using Ethernet cables. These are installed in your crawl space, attic or outside along the soffits. An Audio Video contractor can install these Ethernet cables to jacks in your walls in the room with your router and any other room in the house where you want Internet service without having to use Wi-Fi. You then purchase an Ethernet cable and plug that into the wall jack and into your computer. If your computers are all in the same room, you can simply run Ethernet cables that you purchase at the store from the router to each computer in the room. If you run out of Ethernet jacks or ports on the back of the router, you can purchase an Ethernet Switch, also known as a Hub, that connects to the router using an Ethernet cable. This gives you more ports for more Ethernet cables connected to more devices.
If you have more than one device in the distant room that needs to be connected to the Internet, you can put a Switch or Hub in that room and then connect to each device with Ethernet cables plugged into the Switch.
You can add printers to this network and print from any computer in the house that is also plugged into this unit, just as you do now with Wi-Fi.
You can also now hook up your TV/Entertainment Center to your router over this hardwired network, rather than using Wi-Fi, in order to stream movies and TV shows from such companies as Netflix and Hulu. You will need a decoder at the TV that does not produce Wi-Fi, as the Apple TV unit does. I have heard conflicting information about Roku about being able to disable the Wi-Fi on that unit at the TV. Inquire about disabling Wi-Fi in the unit at the TV when you connect your TV to the Internet for streaming media.>
If you don't want to or can't install Ethernet cables in your house, there are two other options to get your Internet to distant rooms without using Wi-Fi. The first technology puts the Internet signal onto existing electric circuits and the other uses the existing coaxial cables that usually already exists for television service.
Network Extenders Using Electric Circuits
The first technology uses a pair of Network Extenders, such as the Netgear Powerline series. The Powerline 500 model carries up to 500 Megabits of data per second (Mbps). Purchase Model XAVB5101 at Amazon for roughly $66 by clicking here.
There is also a less expensive model that is not quite as fast (200 Mbps), Model XAVB2101, available here. It retails for about $48.
Don't purchase a model of network extender that has Wi-Fi built in (the models listed above do not). See below for details.
You are purchasing a pair of network extenders in each box. One unit goes in the room with the router, and the other unit goes anywhere in the house that you want to use your computer. Each unit plugs into an electric outlet, so while one unit stays with the router, you can move the other unit around as you move the location of your laptop or desktop computer.
First plug one unit directly into an outlet (not a power strip, surge protector or extension cord) that is near the router. An Ethernet jack exists on the side of each unit. Plug that Ethernet cable into the back of your router and into the Ethernet jack on the side of the network extender. They provide you with two 6-foot Ethernet cables in the box when you buy the units, but if that 6-foot cord is not long enough to reach an available electric outlet in the room with the router, then just order a longer Ethernet cable from Amazon when you purchase the network extender. For example, you can purchase a 14-foot Ethernet cable for $5.49 by clicking here. If you need a cable longer than that, just put "Ethernet Cable" in the Amazon search box.
Plug the second unit into an outlet anywhere you want to use your computer. Then connect another Ethernet cable to the jack on the side of the network extender unit and to the Ethernet jack or port on your laptop or desktop computer. For a Mac Air, which has no Ethernet port, you can purchase from Apple a USB to Ethernet adapter for $29 by clicking here or a Thunderbolt to Ethernet adapter for $29 by clicking here.
Be sure to then turn off the Wi-Fi on your laptop or desktop computer, if the desktop has Wi-Fi (many older models do not). If you plug an Ethernet cable into your laptop or desktop and assume that doing so automatically disables the Wi-Fi, you will unfortunately continue to experience the constant transmission of a radio signal by the computer every few seconds looking for a Wi-Fi router, even with an Ethernet cable plugged in and no Wi-Fi on in the house. You must manually disable the Wi-Fi on your computer. I show you how to do this below.
Be aware that at the present time there is no Ethernet port (nor even a USB port) on an iPad, but you can connect a Microsoft Surface tablet, at least the Surface 2 or Surface Pro, model to an Ethernet cable using an Ethernet to USB adapter. This is available from Microsoft. It plugs into the USB port on the side of the Surface 2 or Surface Pro tablet — but not the basic Surface model. Then put the Surface tablet into Airplane mode to eliminate the Wi-Fi. iPads do not have a USB port and so you cannot connect an iPad to the Internet with an Ethernet cord.
Pay attention to the instructions that come with the network extenders that say you get the best results if you plug each unit directly into an electric outlet rather than into a surge protector, power strip or extension cord. We recommend that you instead use a Surface 2 or Surface Pro tablet, or the Mac Air ultra-small and lightweight laptop, or your regular laptop.
If you have more than one computer that you want to remotely connect to a router using the electric circuits, the you will need to purchase a separate pair of network extenders for each device. You will need to plug one of the network extender pairs into its own outlet and run an Ethernet cable from each unit to the back of the router or Switch, providing a separate set up for each remote device. You cannot share two remote computers on one network extender device plugged into the router. The remote network extender unit synchs up with its matching unit in the pair that comes in the box.
If you purchase another model from Netgear or from another company other than the models listed above, be sure that the network adapter you purchase does not have a Wi-Fi access point transmitter in the unit you plug in somewhere else in the house beyond where the router is. Netgear and other companies do make network extenders for that purpose, to send the Internet signal over the electrical circuits to a distant part of the house where the network extender unit you plug in then transmits a Wi-Fi signal. You only want this remote unit to provide an Internet signal from the Ethernet jack on the side through an Ethernet cable to your computer and not also transmit a Wi-Fi signal into this room.
If you are electrically sensitive to high frequencies (dirty electricity), network extender technology may not be for you. Since the Internet signal travels on the electric cables at the zero crossing point of the 60 Hz sine wave, it may emit some frequencies off electric wires, which are not fully shielded. (This is true even with metal-clad wiring, which shields electric fields but not magnetic fields below 1 MHz, and most dirty electricity is below 1 Mhz. Even if you have metal clad electrical wiring, you still also have plastic AC appliance power cords plugged into outlets throughout the house, and they can possibly emit harmonic frequencies of dirty electricity, if it exists, both the electric and magnetic components).
Instead, if you are sensitive to dirty electricity or you don't want to install Ethernet cables, you have two other options to provide remote Internet in your house: The first is to hire an Audio Video contractor to install Ethernet cables in your crawl space, attic or outside along the soffits. Ethernet cables are shielded.
Multimedia Over Cable Alliance Technology (MOCA)
The other option is to use MOCA, or multimedia over cable alliance technology. The device they use is called an Ethernet to Coax Adapter Kit for Homes with Cable TV Service. This sends the Internet signal over existing coaxial cables in your house, which are shielded, even if you already use your coaxial cables for TV service.
In one room you connect one Ethernet to Coax adapter unit to your router using a provided Ethernet cable. You then connect the unit to a nearby coaxial cable using the provided coaxial cable. Then connect the other adapter unit to a computer in another room anywhere in the house using another Ethernet cable and connect the unit to a nearby coaxial cable jack in a wall in that room. This assumes your coaxial cables are connected and you have a continuous path. If not, you will need an Audio Video contractor to make sure the coaxial cable is continuous.
The Ethernet to Coax Adapter Kit is available by clicking here. The kit retails for $106 and is advertised to send data at speeds up to 270 Mbps. There will be instructions on how to install them.
Putting aside cost and throughput speed considerations, of the two, the coaxial cable solution is perhaps better because the coaxial cable is shielded, while the electric circuit, which is the path that the network extender over power lines uses, is not. Therefore the coax is a better choice from an EMF standpoint, but if coaxial jacks are not available in either room and you are not electrically hypersensitive, then use the Netgear network extender over circuits. Installing Ethernet cables is always the best solution, particularly for electrically hypersensitive clients.
Disabling Wi-Fi on a Router
Don't forget to then disable the Wi-Fi on your computer, as well as your router. To disable the Wi-Fi broadcast feature of the router, this can be done using any computer that is connected to the router with an Ethernet cable from any room in the house. The router will stay on and function as a hardwired router but the Wi-Fi will be turned off. I can assist you with this if you are in Southern California, or you can call the Technical Services department of your router manufacturer and they will walk you through it.
This will involve opening your browser and typing in a string of numbers instead of a web address. This opens the Control Panel of the router that the computer is connected to. Once you enter the correct username and password, you must then find the wireless network setup page, where you can disable the Wi-Fi. You can bookmark this page so you can easily disable and enable the Wi-Fi, if other family members need it, with just two or three clicks. Unless you are computer savvy, however, you will need assistance to do this.
Disabling Wi-Fi on a Mac
You will also need to disable the Wi-Fi on your laptop or desktop computer (if it has built-in Wi-Fi). If you don't, your computer will continue to put out freqeuncies as the computer tries to find a Wi-Fi router in the area, even if you are now connected to your router with an Ethernet cable.
To disable the Wi-Fi on a Mac laptop or iMac, first make sure your Ethernet cable is plugged into the Ethernet jack and that you are connected to the Internet. Then find the wedge-shaped icon, located in the upper right corner of the menu bar to the left of the volume icon and the day and time. If the Wi-Fi is on, you will see black or gray curved bars in the wedge (black if there is a strong Wi-Fi signal close by, and gray if it is weak or non-existent). Next, click on the wedge-shaped icon. The first line of the drop down menu will say, "Wi-Fi: On". If so, and you are ready to disable it, then click on the second line, which currently says, "Turn Wi-Fi Off". That turns off the Wi-Fi and the curved lines go away. You want to see an empty wedge-shaped icon. That means there is no Wi-Fi signal coming from the computer.
Next, make sure you are still connected to the Internet. If your Ethernet connection is good and the technology you use to get that Internet signal to your computer over the Ethernet cable is good, you should still be able to get onto the Internet. In fact, hardwired connections are usually faster, more stable and more secure than wireless connections, and there are no radio frequency EMFs.
(You also want to make sure the BlueTooth icon, to the left of the wedge-shaped icon, is also disabled (gray versus black), because if it is enabled, the computer will send out a BlueTooth radio signal to connect to a wireless device such as a wireless mouse or keyboard, and the wireless mouse and keyboard themselves send out a continuous radio signal. If you have a wireless mouse and / or keyboard, we highly recommend that you replace these with a hardwired mouse and keyboard. Then turn the BlueTooth off in the wireless mouse and keyboard, because if you don't, they can still transmit a signal in a drawer until the battery within them runs out.)
Disabling Wi-Fi on a PC Laptop
To disable the Wi-Fi on a PC laptop, there is often a button that turns this on and off. If not, and you have Windows XP operating system, open the control panel and click on "Network Connections." You will see an icon for the "LAN or High-Speed Internet," which will say "Connected." That means you are connected through the Ethernet cable. Leave that alone. Look for the icon that says "Wireless." You want to right-click that and click to make it "Disabled."
The Choice of Using Wireless Tablets Compared to New, Slim, Lightweight Laptops
Tablets are very popular these days, and more and more people are switching over to using them for everything they did on their computer, including surfing the web and email. There is a problem with them, however, and for that reason, we recommend that clients choose one of the newer laptops on the market, such as the Mac Air.
The reason why we prefer a Mac Air, and any other new, slim, lightweight laptop, to tablets is because you cannot connect to the Internet with a tablet any other way except wirelessly. The only jack on a tablet is used to recharge the battery and to synch up with a computer to exchange and download files, but I was told that these tablets do not allow you to access the Internet through a computer that it is synched up with.
Any laptop, however, including the Mac Air, will have one or more USB ports. With all but the latest slim laptops, you can plug an Ethernet cable directly into the Ethernet jack on the side or back of the laptop. You can then get a long Ethernet cord and connect to the Internet that way, turning off the Wi-Fi feature on the laptop so you don't get exposed to the radio frequencies that still come out of the laptop as it looks for a Wi-Fi enabled router even if an Ethernet cable is plugged in.
Since the Mac Air is so slim, however, it does not have an Ethernet jack, but you can purchase a USB to Ethernet adapter cable from Apple that you can plug into one of its USB ports and then plug an Ethernet cable into the other end of the adapter
Then you can plug the other end of the Ethernet cable into any Ethernet jack on your router or in your wall, if you have an Ethernet network in your house. You should then put your Mac Air into Airplane mode, which shuts off the Wi-Fi radio broadcast feature, since you don't need it until you take the tablet out of the house.
When you leave home, you can then take your Mac Air out of Airplane mode to get onto the Internet using Wi-Fi. However, remember that now you are in the presence of "second-hand smoke," so to speak, so keep your use to a minimum until you can get back to a hardwired connection. Or, take an Ethernet cable with you, keep the Mac Air on Airplane mode and plug into an Ethernet jack at the coffee shop or library, if they have one, or at the hotel. Most hotel rooms still have an Ethernet jack available.
Harmonic Frequencies of "Dirty Electricity"
In computers and printers, dirty electricity can be produced by small, chip-based transformers used to step power down or up from one voltage to another.
A typical computer has circuit boards that run on up to five different voltages, so the 19 or so Volts that enters the computer, having been stepped down from 120 Volts by the first, usually linear transformer (that does not produce dirty electricity), is then dropped further down to various voltages for the different circuit boards. It is a switched mode power supply that does this reduction.
In the process, however, switched mode power supplies change the configuration of the 60 Hz sine wave of electricity within the computer, and this spills out onto the electricity travelling within our circuits from the electric utility.
Since we need to use our computers, the only way to really decrease dirty electricity in computers and printers is with dirty electricity reduction technologies, such as filters sold by Greenwave and the RxDNA and PxDNA units sold by RFReduce. These are discussed in detail in my article on Dirty Electricity, that you can link to by clicking here.
Protection From EMFs Caused By House Wiring
For steps to protect you and your family from the effects of electric and magnetic fields from house wiring, see "Tips for a Healthy Home" on this website by clicking here.
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