do display screens give out harmful radiation quotation

According to the American Academy of Ophthalmology (AAO), "there is no convincing scientific evidence that computer video display terminals (VDTs) are harmful to the eyes."  The common complaints of eye discomfort and fatigue are associated with ergonomic factors such as distance from the person to the monitor, monitor height and brightness, etc.

I have a colleague who is pregnant and who types at a computer. How much radiation does her baby receive at a typical computer? Is there a lead shield that she could wear? Like an apron?

Regulations of the US Department of Health and Human Services require manufacturers to test computer monitor emissions for radiation and to label them attesting to the fact that they have been found to meet the standards of Title 21 of the Code of Federal Regulations. You should be able to find this label on the rear of the computer monitor or the computer processor. Health studies of pregnant women who work with VDTs have not found harmful effects on the women or on their children. Heavy lead aprons or other shields are not considered necessary for units that meet the x-ray emission standards of 21 CFR. Such shields may actually be counterproductive from an ergonomic point of view.

Radiation emissions from VDTs (for example, television sets and computer monitors) are regulated by the US Food and Drug Administration (FDA) and manufacturers are required to test and label these products.  Regulations limit radiation emissions from electronic products to levels considered safe.

I have heard a lot of answers about the ill effects of computer radiation but almost all that I have read claim no certainty in their answers. Has there been any valid and indisputable answer to this?

This means that if there are health risks they are too small or of a kind that have not been detected by current methods. Scientists often say that they "cannot disprove a negative," meaning that it is not logically possible to prove that something does not exist. This is because the list of things to be disproved can be endless, and the type and level of sensitivity of the tests that are used can always be improved upon.

I"m getting a computer for my child and would like to know which type of monitor/computer is safest in terms of the different types of radiation that exist. I was told years ago that the flat screens had a different, yet worse, type of radiation. Are there two types of radiation, and is this type worse?

All television receivers (including computer monitors), regardless of type, must meet a mandatory federal performance standard so any x-ray emissions, if they exist at all, must be at very low levels.  I am unaware of two types of radiation, unless you categorize the visible light which you see on the television screen as one type, which is, in fact an electromagnetic radiation; You can also consider radiowaves, which are also electromagnetic radiation. Both of these types of radiation are nonionizing and generally considered safe unless one is exposed to very intense levels.

All television receivers (including computer monitors), regardless of type, must meet a mandatory federal performance standard so any x-ray emissions, if they exist at all, must be at very low levels. The key point is that the emission standard is for "any point on the external surface" which means whether someone is in front of, to the side of, or behind the display or receiver, he/she is protected against any potential emissions of the display to the same degree.

My mom worries about the effects of computer radiation. She says that I am putting my health at risk by being on my PC more than four hours a day. Is this true?

The radiation emission from any computer is RF (radiofrequency) waves. There is no proof that these are harmful unless the intensity is high enough to warm tissue (like a microwave oven). You are not putting yourself at risk (from radiation) by being on your computer more than four hours a day.

My grandchildren often sit with their laptop computers in their laps. Is there any danger to their health and reproductive organs from low-level radiation that may be reaching them?

The only measurable radiation emission from a laptop computer is radio waves. We are constantly exposed to such radiation from all directions and multiple sources, including radio and TV signals, electronic appliances, etc. Current data indicate that these are not harmful to our health. There is, however, quite a bit of heat generated within the laptop while it is on. It is for this reason manufacturers recommend against extended periods of use with the computer on your lap.

The information posted on this web page is intended as general reference information only. Specific facts and circumstances may affect the applicability of concepts, materials, and information described herein. The information provided is not a substitute for professional advice and should not be relied upon in the absence of such professional advice. To the best of our knowledge, answers are correct at the time they are posted. Be advised that over time, requirements could change, new data could be made available, and Internet links could change, affecting the correctness of the answers. Answers are the professional opinions of the expert responding to each question; they do not necessarily represent the position of the Health Physics Society.

In this post, I’m going to tell you how computer monitors emit EMF radiation, how much they emit, how you can test this, and what you can do about it.

(Just a quick note before we move on. I would love for you to take just a minute and check out Nicolas Pineault’s groundbreaking E-book “A Non-Tinfoil Guide To EMFs.” It is the most entertaining and informative book on EMF radiation you’ll ever read, I promise.)

There are primarily three types of radiation sources that a computer monitor is likely to have, UV light radiation, x-ray radiation, and EMF radiation. Which radiation, and how much they emit, will depend largely on the monitor. Let’s talk a little bit about each kind.

There are basically two categories of monitors: cathode-ray tubes, and the flat-screen monitors that you see today, which are typically either LED or LCD based screens.

Prior to about 2001, almost all monitors were using cathode-ray tube (CRT) technology to power the screens. However, these types of monitors generate, and leak, small amounts of highly dangerous X-Ray Radiation. Although this had been recognized since the 60’s as being dangerous, it was not until the late 1990’s that manufacturers really fell under scrutiny for continuing to make a knowingly dangerous product.

This led to the manufacturing of Light Emitting Diode (LED) and liquid crystal display (LCD), which is what I used for nearly all modern monitors (and televisions)

Exposure to x-radiation is obviously extremely harmful and is an unfortunate bi-product of older style cathode ray tube (CRT) type monitors. The electronics in these old monitors generated extremely high voltages that would often result in x-ray radiation.

Although x-radiation that you could receive from one of these older style CRT monitors is dangerous and harmful, it is much less than you would receive from a medical x-ray machine or the x-ray at the dentist. This is the reason that they have you wear led vests to protect your body from the radiation.

Later versions of CRT monitors were slightly safer, as manufacturers began to take steps to reduce this x-ray radiation by adding lead to the cathode ray tube, which helped to cut down on this issue.

The EMF meter that the gentleman is using in this video is the older version of the Trifield meter, the company now has the new TriField TF2 (read my review), but we’ll talk about that a bit more down below in the section about measuring computer monitor radiation.

Ultraviolet light (UV) is much less harmful than x-ray radiation, but high amounts over a long period of time can still certainly cause harm. Some monitors actually have a fluorescent lamp that is part of the illumination. When the ultraviolet light strikes a white phosphor, the visible light that you see is created, but it has the side effect of sometimes leaking ultraviolet light out.

Luckily they make screen protectors for computer monitors that not only block 100% of the UV light but also help to filter out blue lights that can cause computer vision syndrome (CVS) from longterm exposure to computer monitors.

The EMF Radiation from your computer monitor will be relatively small and come from circuitry in the back of the unit. As you can see from the video above when he is testing an LCD monitor, there is still a noticeable amount of EMF radiation, but you have to be quite close.

This amount of radiation is enough to cause damage over time. In fact, a study showed that the radiation emitted from a monitor was enough to destabilize the oxidant/antioxidant balance in the cornea’s of rats over even a small amount of time.

The Long Island Power Authority did a study where they measured the average EMF radiation from many home appliances. Although they did not specifically test LCD or led computer monitors, they did test led and LCD televisions. Here are the numbers they came up with at the following distances:

As you can see, there is quite a large amount of EMF radiation at VERY close distances, but if you sit at least three feet away from the screen, you will not much need to worry about EMF radiation exposure. Be sure that you don’t sit so far away that you strain your eyes, but do keep at least 3 feet between you and the screen.

This applies to almost anything that you want to test, but you first need to start by getting a high-quality EMF meter. I personally use, and love, the new TriField TF2 (read my review). It is super easy to use, incredibly accurate, and measures every kind of EMF radiation, which you’ll realize is really important. If you need to start with a lower cost version I also like the Meterk (read my review).

Getting a good EMF meter is one of the absolute best things you can do if you care about the dangers of EMF radiation. Whether it’s figuring out how much radiation your Smart Meter is emitting, or testing to see if your microwave is leaking radiation, or comparing cell phone radiation, having a good EMF meter is the first step in knowing what the problem is, and knowing if your solutions are working.

Now, to test the radiation from a computer monitor, start by turning the monitor off, and getting a baseline reading near it. Then, turn the monitor on and give it a few seconds to boot up.

Start from about 5 feet away, and slowly move towards the monitor with your meter. Take notes of the radiation levels at different distances and note how it exponentially increases as you get within a few inches.

First of all, computer monitors do emit a relatively small amount of EMF radiation at reasonable distances. So the absolute best thing you can do is keep at least a reasonable distance (3 feet or more) between you and the monitor whenever possible.

They don’t seem to make a good shield for computer monitors that are actually intended to block EMF radiation, but they do make this window film that you can pick up on Amazon, that you could cut to fit the size of your monitor if you really wanted to reduce the amount of radiation you’re exposing yourself to.

Although it won’t block radiation, if you are staring at a computer or tv quite a bit during your day, you should consider picking up a pair of glasses that block the blue light rays. This will help protect your eyes from long term exposure.

Since the advent of modern flat-panel screens, the vast majority of computer monitors have few, if any, radiation safety issues. The older technology used with vintage monitors, however, does have a potential for emitting certain types of harmful radiation, though manufacturers were aware of the risks and designed them to be safe. Overall, radiation safety issues from monitors are very minor and easily mitigated.

Monitor Types Computer monitors have used two basic types of technology: traditional cathode-ray tubes and more modern flat-screen designs. Before 2000, most computer equipment makers produced CRT-based monitors. These create images by sending a high-voltage beam of electrons in a vacuum tube to a phosphor screen, causing it to glow. The high voltage generates weak forms of radiation, a fact manufacturers have recognized since color TVs became widespread in the 1960s. Flat-screen monitors, by contrast, dispense with the CRT, creating images using a finely detailed grid of liquid crystals. Inside a flat-screen monitor, a bright lamp produces white light, which the liquid crystals filter into a broad range of colors. Although this technology uses low voltages, some of the lamps used produce mild radiation.

Radiation Types The radiation that comes from computer monitors takes the form of X-rays and ultraviolet light. This is not the same radiation normally associated with radioactive materials such as uranium, although it is associated with long-term exposure risks to living things. Of the two radiation types, X-rays are more harmful as they have more energy. Where monitor designs have the potential to produce X-rays or UV, the manufacturer adds materials that block the radiation, greatly reducing the safety issue.

X-Rays Traditional CRT-based monitors use high voltages that generate X-rays. The voltages used in black-and-white monitors is much lower than that found in color models, so X-rays are an issue only for the latter type. X-rays from a computer monitor are much weaker than those produced in a medical X-ray, as the operating voltage is lower and the radiation is a side effect, not the intended purpose of the design. CRT manufacturers solved the X-ray problem by adding lead to the glass picture-tube material.

Ultraviolet Although ultraviolet light is less harmful than X-rays, high levels of UV can burn skin and even cause blindness. Some flat-panel computer displays employ a fluorescent lamp as a bright light source. In the lamp, ultraviolet light strikes a white phosphor, creating visible light, but a small amount of the UV also escapes. In most LCD monitor designs, a layer of plastic absorbs the UV, minimizing the safety risk. Some flat-screen computer monitors use light-emitting diodes in place of fluorescent lighting, eliminating the UV problem completely.

Even the World Health Organization admits that EMF radiation at certain levels can trigger symptoms like headaches, stress, suicide by depression, vomiting, fatigue, and loss of libido.

Unlike the two products mentioned so far, this Screen Protector exclusively obstructs blue light. It’s not mean to attenuate radiation but to shield your eyes from the harmful effects of blue light.

Yes, but it’s mostly the old CRT monitors that are concerning. Newer LCD screens don’t emit as much. The more immediate threat stems from the blue light they emit.

It depends on your distance from the monitor. Inches away would give you 25-500 mG of EMF radiation, 1 foot emits 0.4-20 mG, while 3 feet emits just 0.1-1.5 mG of radiation.

Monitors emit such a low level of radiation that most agree it’s not a concern. However, even low levels over long periods of time have induced side effects like headaches and depression.

Certified EMF Expert, Chief Editor & Researcher at Beat EMF. I’m in charge of testing all the products and sorting through the duds to deliver effective EMF solutions for your family. Learn more about me here.

Electromagnetic radiation consists of waves of electric and magnetic energy moving together (i.e., radiating) through space at the speed of light.  Taken together, all forms of electromagnetic energy are referred to as the electromagnetic "spectrum."  Radio waves and microwaves emitted by transmitting antennas are one form of electromagnetic energy.  They are collectively referred to as "radiofrequency" or "RF" energy or radiation.  Note that the term “radiation” does not mean “radioactive.”  Often, the terms "electromagnetic field" or "radiofrequency field" are used to indicate the presence of electromagnetic or RF energy.

The RF waves emanating from an antenna are generated by the movement of electrical charges in the antenna.  Electromagnetic waves can be characterized by a wavelength and a frequency.  The wavelength is the distance covered by one complete cycle of the electromagnetic wave, while the frequency is the number of electromagnetic waves passing a given point in one second.  The frequency of an RF signal is usually expressed in terms of a unit called the "hertz" (abbreviated "Hz").  One Hz equals one cycle per second.  One megahertz MHz equals one million cycles per second.

Different forms of electromagnetic energy are categorized by their wavelengths and frequencies.  The RF part of the electromagnetic spectrum is generally defined as that part of the spectrum where electromagnetic waves have frequencies in the range of about 3 kilohertz (3 kHz) to 300 gigahertz (300 GHz).  Microwaves are a specific category of radio waves that can be loosely defined as radiofrequency energy at frequencies ranging from about 1 GHz to 30 GHz. (Back to Index)

"Ionization" is a process by which electrons are stripped from atoms and molecules.  This process can produce molecular changes that can lead to damage in biological tissue, including effects on DNA, the genetic material of living organisms.  This process requires interaction with high levels of electromagnetic energy.  Those types of electromagnetic radiation with enough energy to ionize biological material include X-radiation and gamma radiation.  Therefore, X-rays and gamma rays are examples of ionizing radiation.

The energy levels associated with RF and microwave radiation, on the other hand, are not great enough to cause the ionization of atoms and molecules, and RF energy is, therefore, is a type of non-ionizing radiation.  Other types of non-ionizing radiation include visible and infrared light.  Often the term "radiation" is used, colloquially, to imply that ionizing radiation (radioactivity), such as that associated with nuclear power plants, is present.  Ionizing radiation should not be confused with the lower-energy, non-ionizing radiation with respect to possible biological effects, since the mechanisms of action are quite different. (Back to Index)

The most important use for RF energy is in providing telecommunications services.  Radio and television broadcasting, cellular telephones, personal communications services (PCS), pagers, cordless telephones, business radio, radio communications for police and fire departments, amateur radio, microwave point-to-point links and satellite communications are just a few of the many telecommunications applications of RF energy.  Microwave ovens are an example of a non-telecommunication use of RF energy.  Radiofrequency radiation, especially at microwave frequencies, can transfer energy to water molecules.  High levels of microwave energy will generate heat in water-rich materials such as most foods.  This efficient absorption of microwave energy via water molecules results in rapid heating throughout an object, thus allowing food to be cooked more quickly in a microwave oven than in a conventional oven.  Other important non-telecommunication uses of RF energy include radar and industrial heating and sealing.  Radar is a valuable tool used in many applications range from traffic speed enforcement to air traffic control and military surveillance.  Industrial heaters and sealers generate intense levels of RF radiation that rapidly heats the material being processed in the same way that a microwave oven cooks food.  These devices have many uses in industry, including molding plastic materials, gluing wood products, sealing items such as shoes and pocketbooks, and processing food products.  There are also a number of medical applications of RF energy, such as diathermy and magnetic resonance imaging (MRI). (Back to Index)

An RF electromagnetic wave has both an electric and a magnetic component (electric field and magnetic field), and it is often convenient to express the intensity of the RF environment at a given location in terms of units specific to each component. For example, the unit "volts per meter" (V/m) is used to express the strength of the electric field (electric "field strength"), and the unit "amperes per meter" (A/m) is used to express the strength of the magnetic field (magnetic "field strength").  Another commonly used unit for characterizing the total electromagnetic field is "power density."  Power density is most appropriately used when the point of measurement is far enough away from an antenna to be located in the "far-field" zone of the antenna.

The quantity used to measure the rate at which RF energy is actually absorbed in a body is called the "Specific Absorption Rate" or "SAR."  It is usually expressed in units of watts per kilogram (W/kg) or milliwatts per gram (mW/g).  In the case of exposure of the whole body, a standing ungrounded human adult absorbs RF energy at a maximum rate when the frequency of the RF radiation is in the range of about 70 MHz.  This means that the "whole-body" SAR is at a maximum under these conditions.  Because of this "resonance" phenomenon and consideration of children and grounded adults, RF safety standards are generally most restrictive in the frequency range of about 30 to 300 MHz.  For exposure of parts of the body, such as the exposure from hand-held mobile phones, "partial-body" SAR limits are used in the safety standards to control absorption of RF energy (see later questions on mobile phones).  (Back to Index)

Biological effects can result from exposure to RF energy.  Biological effects that result from heating of tissue by RF energy are often referred to as "thermal" effects.  It has been known for many years that exposure to very high levels of RF radiation can be harmful due to the ability of RF energy to heat biological tissue rapidly.  This is the principle by which microwave ovens cook food.  Exposure to very high RF intensities can result in heating of biological tissue and an increase in body temperature.  Tissue damage in humans could occur during exposure to high RF levels because of the body"s inability to cope with or dissipate the excessive heat that could be generated.  Two areas of the body, the eyes and the testes, are particularly vulnerable to RF heating because of the relative lack of available blood flow to dissipate the excess heat load.

At relatively low levels of exposure to RF radiation, i.e., levels lower than those that would produce significant heating, the evidence for production of harmful biological effects is ambiguous and unproven.  Such effects, if they exist, have been referred to as "non-thermal" effects.  A number of reports have appeared in the scientific literature describing the observation of a range of biological effects resulting from exposure to low levels of RF energy.  However, in most cases, further experimental research has been unable to reproduce these effects.  Furthermore, since much of the research is not done on whole bodies (in vivo), there has been no determination that such effects constitute a human health hazard.  It is generally agreed that further research is needed to determine the generality of such effects and their possible relevance, if any, to human health.  In the meantime, standards-setting organizations and government agencies continue to monitor the latest experimental findings to confirm their validity and determine whether changes in safety limits are needed to protect human health. (Back to Index)

Studies have shown that environmental levels of RF energy routinely encountered by the general public are typically far below levels necessary to produce significant heating and increased body temperature.  However, there may be situations, particularly in workplace environments near high-powered RF sources, where the recommended limits for safe exposure of human beings to RF energy could be exceeded.  In such cases, restrictive measures or mitigation actions may be necessary to ensure the safe use of RF energy. (Back to Index)

Some studies have also examined the possibility of a link between RF exposure and cancer.  Results to date have been inconclusive.  While some experimental data have suggested a possible link between exposure and tumor formation in animals exposed under certain specific conditions, the results have not been independently replicated.  Many other studies have failed to find evidence for a link to cancer or any related condition.  The Food and Drug Administration has further information on this topic with respect to RF exposure from mobile phones at the following Web site: FDA Radiation-Emitting Products Page . (Back to Index)

For many years, research into the possible biological effects of RF energy has been carried out in laboratories around the world, and such research is continuing.  Past research has resulted in a large number of peer-reviewed scientific publications on this topic.  For many years the U.S. Government has sponsored research into the biological effects of RF energy.  The majority of this work was initiated by the Department of Defense, due in part, to the extensive military interest in using RF equipment such as radar and other relatively high-powered radio transmitters for routine military operations.  In addition, some U.S. civilian federal agencies responsible for health and safety, such as the Environmental Protection Agency (EPA) and the U.S. Food and Drug Administration (FDA), have sponsored and conducted research in this area.  At the present time, other U.S. civilian federal health and safety agencies and institutions, such as the National Toxicology Program and the National Institutes of Health, have also initiated RF bioeffects research.

In 1996, the World Health Organization (WHO) established a program called the International EMF Project, which is designed to review the scientific literature concerning biological effects of electromagnetic fields, identify gaps in knowledge about such effects, recommend research needs, and work towards international resolution of health concerns over the use of RF technology.  The WHO maintains a Web site that provides extensive information on this project and about RF biological effects and research (www.who.int/peh-emf/en/).

The FDA, the EPA and other federal agencies responsible for public health and safety have worked together and in connection with the WHO to monitor developments and identify research needs related to RF biological effects.  More information about this can be obtained at the FDA Web site: FDA Radiation-Emitting Products - Current Research. (Back to Index)

Exposure standards for radiofrequency energy have been developed by various organizations and governments.  Most modern standards recommend safe levels of exposure separately for the general public and for workers.  In the United States, the FCC has adopted and used recognized safety guidelines for evaluating RF environmental exposure since 1985.  Federal health and safety agencies, such as the EPA, FDA, the National Institute for Occupational Safety and Health (NIOSH) and the Occupational Safety and Health Administration (OSHA) have also been involved in monitoring and investigating issues related to RF exposure.

The FCC guidelines for human exposure to RF electromagnetic fields were derived from the recommendations of two expert organizations, the National Council on Radiation Protection and Measurements (NCRP) and the Institute of Electrical and Electronics Engineers (IEEE).  Both the NCRP exposure criteria and the IEEE standard were developed by expert scientists and engineers after extensive reviews of the scientific literature related to RF biological effects.  The exposure guidelines are based on thresholds for known adverse effects, and they incorporate prudent margins of safety.  In adopting the current RF exposure guidelines, the FCC consulted with the EPA, FDA, OSHA and NIOSH, and obtained their support for the guidelines that the FCC is using.

Many countries in Europe and elsewhere use exposure guidelines developed by the International Commission on Non-Ionizing Radiation Protection (ICNIRP).  The ICNIRP safety limits are generally similar to those of the NCRP and IEEE, with a few exceptions.  For example, ICNIRP recommends somewhat different exposure levels in the lower and upper frequency ranges and for localized exposure due to such devices as hand-held cellular telephones.  One of the goals of the WHO EMF Project (see above) is to provide a framework for international harmonization of RF safety standards.  The NCRP, IEEE and ICNIRP exposure guidelines identify the same threshold level at which harmful biological effects may occur, and the values for Maximum Permissible Exposure (MPE) recommended for electric and magnetic field strength and power density in both documents are based on this level.  The threshold level is a Specific Absorption Rate (SAR) value for the whole body of 4 watts per kilogram (4 W/kg).

The FCC authorizes and licenses devices, transmitters and facilities that generate RF radiation.  It has jurisdiction over all transmitting services in the U.S. except those specifically operated by the Federal Government.  However, the FCC"s primary jurisdiction does not lie in the health and safety area, and it must rely on other agencies and organizations for guidance in these matters.

Under the National Environmental Policy Act of 1969 (NEPA), all Federal agencies are required to implement procedures to make environmental consideration a necessary part of an agency"s decision-making process.  Therefore, FCC approval and licensing of transmitters and facilities must be evaluated for significant impact on the environment.  Human exposure to RF radiation emitted by FCC-regulated transmitters is one of several factors that must be considered in such environmental evaluations.  In 1996, the FCC revised its guidelines for RF exposure as a result of a multi-year proceeding and as required by the Telecommunications Act of 1996.

Facilities under the jurisdiction of the FCC having a high potential for creating significant RF exposure to humans, such as radio and television broadcast stations, satellite-earth stations, experimental radio stations and certain cellular, PCS and paging facilities are required to undergo routine evaluation for compliance with RF exposure guidelines whenever an application is submitted to the FCC for construction or modification of a transmitting facility or renewal of a license.  Failure to show compliance with the FCC"s RF exposure guidelines in the application process could lead to the preparation of a formal Environmental Assessment, possible Environmental Impact Statement and eventual rejection of an application.  Technical guidelines for evaluating compliance with the FCC RF safety requirements can be found in the FCC"s OET Bulletin 65 (see "OET Safety Bulletins" listing elsewhere at this Web site).

Low-powered, intermittent, or inaccessible RF antennas and facilities (including many cell sites) are normally "categorically excluded" from the requirement of routine evaluation for RF exposure.  These exclusions are based on calculations and measurement data indicating that such transmitting stations or devices are unlikely to cause exposures in excess of the guidelines under normal conditions of use.  The FCC"s policies on RF exposure and categorical exclusion can be found in Section 1.1307(b) of the FCC"s Rules and Regulations [47 CFR 1.1307(b)].  It should be emphasized, however, that these exclusions are not exclusions from compliance, but, rather, only exclusions from routine evaluation.  Transmitters or facilities that are otherwise categorically excluded from evaluation may be required, on a case-by-case basis, to demonstrate compliance when evidence of potential non-compliance of the transmitter or facility is brought to the Commission"s attention [see 47 CFR 1.1307(c) and (d)]. (Back to Index)

The FDA, which has primary jurisdiction for investigating mobile phone safety, has stated that it cannot rule out the possibility of risk, but if such a risk exists, "it is probably small."  Further, it has stated that, while there is no proof that cellular telephones can be harmful, concerned individuals can take various precautionary actions, including limiting conversations on hand-held cellular telephones and making greater use of telephones with hands-free kits where there is a greater separation distance between the user and the radiating antenna.  The Web site for the FDA"s Center for Devices and Radiological Health provides further information on mobile phone safety: FDA Radiation-Emitting Products - Cell Phones.

Measurements and analysis of SAR in models of the human head have shown that the 1.6 W/kg limit is unlikely to be exceeded under normal conditions of use of cellular and PCS hand-held phones.  The same can be said for cordless telephones used in the home.  Testing of hand-held phones is normally done under conditions of maximum power usage, thus providing an additional margin of safety, since most phone usage is not at maximum power.  Information on SAR levels for many phones is available electronically through the FCC"s Web site and database (see next question). (Back to Index)

As explained above, the Specific Absorption Rate, or SAR, is the unit used to determine compliance of cellular and PCS phones with safety limits adopted by the FCC.  The SAR is a value that corresponds to the rate at which RF energy absorbed in the head of a user of a wireless handset.  The FCC requires mobile phone manufacturers to demonstrate compliance with an SAR level of 1.6 watts per kilogram (averaged over one gram of tissue).

Information on SAR for a specific cell phone model can be obtained for almost all cellular telephones by using the FCC identification (ID) number for that model.  The FCC ID number is usually printed somewhere on the case of the phone or device.  In many cases, you will have to remove the battery pack to find the number.  Once you have the number proceed as follows. Go to the following website: Equipment Authorization. Click on the link for “FCC ID Search”.  Once you are there you will see instructions for inserting the FCC ID number.  Enter the FCC ID number (in two parts as indicated: "Grantee Code" is comprised of the first three characters, the "Equipment Product Code" is the remainder of the FCC ID).  Then click on "Start Search."  Grant(s) of Equipment Authorization for this particular FCC ID number should then be available.  Click on a check under "Display Grant" and the grant should appear.  Look through the Grant for the section on SAR compliance, certification of compliance with FCC rules for RF exposure, or similar language.  This section should contain the value(s) for typical or maximum SAR for your phone.

For portable phones and devices authorized since June 2, 2000, maximum SAR levels should be noted on the grant of equipment authorization.  For phones and devices authorized between about mid-1998 and June 2000, detailed information on SAR levels is typically found in one of the "exhibits" associated with the grant.  Therefore, once the grant is accessed in the FCC database, the exhibits can be viewed by clicking on the appropriate entry labeled "View Exhibit."  Electronic records for FCC equipment authorization grants were initiated in 1998, so devices manufactured prior to this date may not be included in our electronic database.

Although the FCC database does not list phones by model number, there are certain non-government Web sites such as www.cnet.com, that provide information on SAR from specific models of mobile phones.  However, the FCC has not reviewed these sites for accuracy and makes no guarantees with respect to them.  In addition to these sites, some mobile phone manufacturers make this information available at their own Web sites.  Also, phones certified by the Cellular Telecommunications and Internet Association (CTIA) are now required to provide this information to consumers in the instructional materials that come with the phones.

If you want additional consumer information on safety of cell phones and other transmitting devices please consult the information available below. In particular, you may wish to read or download our further consumer information: Cell Phones: Wireless Devices and Health Concerns, Specific Absorption Rate (SAR) For Cell Phones: What It Means For You, or General Wireless Device FAQ"s. If you have any problems or additional questions you may contact us at: rfsafety@fcc.gov or you may call: 1-888-225-5322 (1-888-CALL-FCC).  You may also wish to consult a consumer update on mobile phone safety published by the U.S. Food and Drug Administration (FDA) that can be found at: FDA Radiation-Emitting Products Page. (Back to Index)

A number of devices have been marketed that claim to "shield" or otherwise reduce RF absorption in the body of the user.  Some of these devices incorporate shielded phone cases, while others involve nothing more than a metallic accessory attached to the phone.  Studies have shown that these devices generally do not work as advertised.  In fact, they may actually increase RF absorption in the head due to their potential to interfere with proper operation of the phone, thus forcing it to increase power to compensate.  The Federal Trade Commission has published a Consumer Alert regarding these shields on its website at: FTC Consumer Information -Cell Phone Radiation Scam. (Back to Index)

The FCC does not normally investigate problems of electromagnetic interference from RF transmitters to medical devices.  Some hospitals have policies, which limit the use of cell phones, due to concerns that sensitive medical equipment could be affected.  The FDA"s Center for Devices and Radiological Health (CDRH) has primary jurisdiction for medical device regulation.  FDA staff has monitored this potential problem and more information is available from the CDRH Web site: http://www.fda.gov/Radiation-EmittingProducts. (Back to Index)

In urban and suburban areas, cellular and PCS service providers commonly use "sector" antennas for their base stations.  These antennas are rectangular panels, e.g., about 1 by 4 feet in size, typically mounted on a rooftop or other structure, but they are also mounted on towers or poles.  Panel antennas are usually arranged in three groups of three each.  It is common that not all antennas are used for the transmission of RF energy; some antennas may be receive-only.

At a given cell site, the total RF power that could be radiated by the antennas depends on the number of radio channels (transmitters) installed, the power of each transmitter, and the type of antenna.  While it is theoretically possible for cell sites to radiate at very high power levels, the maximum power radiated in any direction usually does not exceed 500 watts.

As discussed above, radiofrequency emissions from antennas used for cellular and PCS transmissions result in exposure levels on the ground that are typically thousands of times below safety limits.  These safety limits were adopted by the FCC based on the recommendations of expert organizations and endorsed by agencies of the Federal Government responsible for health and safety.  Therefore, there is no reason to believe that such towers could constitute a potential health hazard to nearby residents or students.

Radio and television broadcast stations transmit their signals via RF electromagnetic waves.  There are thousands of radio and TV stations on the air in the United States.  Broadcast stations transmit at various RF frequencies, depending on the channel, ranging from about 540 kHz for AM radio up to about 700 MHz for UHF television stations.  Frequencies for FM radio and VHF television lie in between these two extremes.  Broadcast transmitter power levels range from less then a watt to more than 100,000 watts.  Some of these transmission systems can be a significant source of RF energy in the local environment, so the FCC requires that broadcast stations submit evidence of compliance with FCC RF guidelines.

Public access to broadcasting antennas is normally restricted so that individuals cannot be exposed to high-level fields that might exist near antennas.  Measurements made by the FCC, EPA and others have shown that ambient RF radiation levels in inhabited areas near broadcasting facilities are typically well below the exposure levels recommended by current standards and guidelines.  There have been a few situations around the country where RF levels in publicly accessible areas have been found to be higher than those recommended in applicable safety standards.  As they have been identified, the FCC has required that stations at those facilities promptly bring their combined operations into compliance with our guidelines.  Thus, despite the relatively high operating powers of many broadcast stations, such cases are unusual, and members of the general public are unlikely to be exposed to RF levels from broadcast towers that exceed FCC limits

Land-mobile communications include a variety of communications systems, which require the use of portable and mobile RF transmitting sources.  These systems operate in several frequency bands between about 30 and 1000 MHz.  Radio systems used by the police and fire departments, radio paging services and business radio are a few examples of these communications systems.  They have the advantage of providing communications links between various fixed and mobile locations.

There are essentially three types of RF transmitters associated with land-mobile systems:  base-station transmitters, vehicle-mounted transmitters, and hand-held transmitters.  The antennas and power levels used for these various transmitters are adapted for their specific purpose.  For example, a base-station antenna must radiate its signal to a relatively large area, and therefore, its transmitter generally has to use higher power levels than a vehicle-mounted or hand-held radio transmitter.  Although base-station antennas usually operate with higher power levels than other types of land-mobile antennas, they are normally inaccessible to the public since they must be mounted at significant heights above ground to provide for adequate signal coverage.  Also, many of these antennas transmit only intermittently.  For these reasons, base-station antennas are generally not of concern with regard to possible hazardous exposure of the public to RF radiation.  Studies at rooftop locations have indicated that high-powered paging antennas may increase the potential for exposure to workers or others with access to such sites, e.g., maintenance personnel.  This could be a concern especially when multiple transmitters are present.  In such cases, restriction of access or other mitigation actions may be necessary.

Hand-held "two-way" portable radios such as walkie-talkies are low-powered devices used to transmit and receive messages over relatively short distances.  Because of the low power levels used, the intermittency of these transmissions ("push-to-talk"), and due to the fact that these radios are held away from the head, they should not expose users to RF energy in excess of safe limits.  Although FCC rules do not require routine documentation of compliance with safety limits for push-to-talk two-way radios as it does for cellular and PCS phones (which transmit continuously during use and which are held against the head), most of these radios are tested and the resulting SAR data are available from the FCC’s Equipment Authorization database.  Click on the link for FCC ID Search. (Back to Index)

The RF signals from these antennas travel in a directed beam from a transmitting antenna to the receiving antenna, and dispersion of microwave energy outside of this narrow beam is minimal or insignificant.  In addition, these antennas transmit using very low power levels, usually on the order of a few watts or less.  Measurements have shown that ground-level power densities due to microwave directional antennas are normally thousands of times or more below recommended safety limits.  Moreover, microwave tower sites are normally inaccessible to the general public.  Significant exposures from these antennas could only occur in the unlikely event that an individual were to stand directly in front of and very close to an antenna for a period of time.

Ground-based antennas used for satellite-earth communications typically are parabolic dish antennas, some as large as 10 to 30 meters in diameter, that are used to transmit uplink or receive downlink microwave signals to or from satellites in orbit around the earth.  These signals allow delivery of a variety of communications services, including television network programming, electronic news gathering and point-of-sale credit card transactions.   Some satellite-earth station antennas are used only to receive RF signals (i.e., like the satellite television antenna used at a residence), and because they do not transmit, RF exposure is not an issue for those antennas.

Although many satellite-earth stations are fixed sites, portable uplink antennas are also used, e.g., for electronic news gathering.  These antennas can be deployed in various locations.  Therefore, precautions may be necessary, such as temporarily restricting access in the vicinity of the antenna, to avoid exposure to the main transmitted beam.  In general, however, it is unlikely that a transmitting earth station antenna would routinely expose members of the public to potentially harmful levels of RF energy. (Back to Index)

To help ensure compliance of amateur radio facilities with RF exposure guidelines, both the FCC and American Radio Relay League (ARRL) have issued publications to assist operators in evaluating compliance for their stations.  The FCC"s publication (Supplement B to OET Bulletin 65) can be viewed and downloaded elsewhere at this Web site (see "OET RF Safety Bulletins"). (Back to Index)

Radiofrequency warning or alerting signs should be used to provide information on the presence of RF radiation or to control exposure to RF radiation within a given area.  Standard radiofrequency hazard warning signs are commercially available from several vendors.  Appropriate signs should incorporate the format recommended by the Institute for Electrical and Electronics Engineers (IEEE) and as specified in the IEEE standard: IEEE Std C95.2-1999 (Web address: http://www.ieee.org).  Guidance concerning the placement of signs can be found in the IEEE Standard: IEEE Std C95.7-2005 (available for free through the IEEE Get Program).  When signs are used, meaningful information should be placed on the sign advising affected persons of:  (1) the nature of the potential hazard (i.e., high RF fields), (2) how to avoid the potential hazard, and (3) whom to contact for additional information.  In some cases, it may be appropriate to also provide instructions to direct individuals as to how to work safely in the RF environment of concern.  Signs should be located prominently in areas that will be readily seen by those persons who may have access to an area where high RF fields are present. (Back to Index)

Over the past several years there has been concern that signals from some RF devices could interfere with the operation of implanted electronic pacemakers and other medical devices.  Because pacemakers are electronic devices, they could be susceptible to electromagnetic signals that could cause them to malfunction.  Some anecdotal claims of such effects in the past involved emissions from microwave ovens.  However, it has never been shown that the RF energy from a properly operating microwave oven is strong enough to cause such interference.

Some studies have shown that mobile phones can interfere with implanted cardiac pacemakers if a phone is used in close proximity (within about 8 inches) of a pacemaker.  It appears that such interference is limited to older pacemakers, which may no longer be in use.  Nonetheless, to avoid this potential problem, pacemaker patients can avoid placing a phone in a pocket close to the location of their pacemaker or otherwise place the phone near the pacemaker location during phone use.  Patients with pacemakers should consult with their physician or the FDA if they believe that they may have a problem related to RF interference.  Further information on this is available from the FDA: http://www.fda.gov/Radiation- EmittingProducts/. (Back to Index)

The Commission does not regulate exposure to emissions from these devices.  Protecting the public from harmful radiation emissions from these consumer products is the responsibility of the U.S. Food and Drug Administration (FDA).  Inquires should be directed to the FDA"s Center for Devices and Radiological Health (CDRH), and, specifically, to the CDRH Office of Compliance at (301) 594-4654. (Back to Index)

The FCC does not have the resources or the personnel to routinely monitor the exposure levels due at all of the thousands of transmitters that are subject to FCC jurisdiction.  However, while there are large variations in exposure levels in the environment of fixed transmitting antennas, it is exceedingly rare for exposure levels to approach FCC public exposure limits in accessible locations.  In addition, the FCC does not routinely perform RF exposure investigations unless there is a reasonable expectation that the FCC exposure limits may be exceeded. (Back to Index)

The FCC does not have a comprehensive, transmitter-specific database for all of the services it regulates.  However, the FCC does have information for some services such as radio and television broadcast stations, and many larger antenna towers are required to register with the Antenna Structure Registration (ASR) database if they meet certain criteria.  In those cases, location information is generally specified in terms of degrees, minutes, and seconds of latitude and longitude.  In some services, licenses are allowed to utilize additional transmitters or to increase power without notifying the FCC.  Other services are licensed by geographic area, such that the FCC has no knowledge concerning the actual number or location of transmitters within that geographic area.

Certain agencies in the Federal Government have been involved in monitoring, researching or regulating issues related to human exposure to RF radiation.  These agencies include the Food and Drug Administration (FDA), the Environmental Protection Agency (EPA), the Occupational Safety and Health Administration (OSHA), the National Institute for Occupational Safety and Health (NIOSH), the National Telecommunications and Information Administration (NTIA) and the Department of Defense (DOD).

By authority of the Radiation Control for Health and Safety Act of 1968, the Center for Devices and Radiological Health (CDRH) of the FDA develops performance standards for the emission of radiation from electronic products including X-ray equipment, other medical devices, television sets, microwave ovens, laser products and sunlamps.  The CDRH established a product performance standard for microwave ovens in 1971 limiting the amount of RF leakage from ovens.  However, the CDRH has not adopted performance standards for other RF-emitting products.  The FDA is, however, the lead federal health agency in monitoring the latest research developments and advising other agencies with respect to the safety of RF-emitting products used by the public, such as cellular and PCS phones.

The FDA"s microwave oven standard is an emission standard (as opposed to an exposure standard) that allows specific levels of microwave energy leakage (measured at five centimeters from the oven surface).  The standard also requires ovens to have two independent interlock systems that prevent the oven from generating microwaves if the latch is released or if the door of the oven is opened.  The FDA has stated that ovens that meet its standards and are used according to the manufacturer"s recommendations are safe for consumer and industrial use.  More information is available from: FDA"s website for Radiation-Emitting Products.

The EPA has, in the past, considered developing federal guidelines for public exposure to RF radiation.  However, EPA activities related to RF safety and health are presently limited to advisory functions.  For example, the EPA chairs an a Radiofrequency Interagency Working Group, which coordinates RF health-related activities among the various federal agencies with health or regulatory responsibilities in this area.

OSHA is part of the U.S. Department of Labor, and is responsible for protecting workers from exposure to hazardous chemical and physical agents.  In 1971, OSHA issued a protection guide for exposure of workers to RF radiation [29 CFR 1910.97].  However, this guide was later ruled to be only advisory and not mandatory. Moreover, it was based on an earlier RF exposure standard that has now been revised.  At the present time, OSHA uses the IEEE and/or FCC exposure guidelines for enforcement purposes under OSHA"s general duty clause (for more information see: www.osha.gov/SLTC/radiofrequencyradiation/).

NIOSH is part of the U.S. Department of Health and Human Services.  It conducts research and investigations into issues related to occupational exposure to chemical and physical agents.  NIOSH has, in the past, undertaken to develop RF exposure guidelines for workers, but final guidelines were never adopted by the agency.  NIOSH conducts safety-related RF studies through its Engineering and Physical Agents Effects-hazards Branch in Cincinnati, Ohio and the Division of Applied Research and Technology (DART).

The NTIA is part of the U.S. Department of Commerce and is responsible for authorizing Federal Government use of the RF electromagnetic spectrum.  Like the FCC, the NTIA also has NEPA responsibilities and has considered adopting guidelines for evaluating RF exposure from U.S. Government transmitters such as radar and military facilities. (Back to Index)

Although relatively few offices or agencies within the Federal Government routinely deal with the issue of human exposure to RF fields, it is possible to obtain information and assistance on certain topics from the following federal agencies, all of which also have Internet Web sites.

You probably know that UV rays emitted by the sun can be damaging to your skin. But what about other types of light, like the warm glow of a computer monitor or smartphone?

Generally, newer model computers feature LCD or LED screens and do not emit harmful UV radiation. But most televisions, computers, smartphones and tablets emit other types of light that some studies show can be harmful to your skin with prolonged exposure.

While it’s doubtful that you’ll be giving up your devices any time soon, there are some things you can do to prevent and repair the signs of potential aging caused by computer and smartphone screens. Here’s what we suggest:

Of course, the best way to minimize the harmful effects of any type of light radiation is to limit your exposure to it, whether that is staying out of the sun or limiting your screen time.

Studies have found that using your electronic devices outdoors can be even more harmful, because the UV radiation from the sun reflects from your smartphone or tablet screen directly onto your face, doubling the impact of dangerous light radiation.

Antioxidants occur naturally in many of the fresh fruits and vegetables we eat. They offer your body many health benefits, including protecting your skin from harmful UV and HEV rays.

Strawberries, blueberries, and kiwis are just a few of the delicious fruits that are packed full of antioxidants. While having an antioxidant-rich diet is crucial to fighting off signs of aging, so is incorporating antioxidants into your daily skin care routine. The Baobab tree, native to the African savannah, has long been known as the “Tree of Life” for its nutrient-rich properties. Our Baobab Skin Correction Facial Cream is made with Baobab seed oil, which is packed full of antioxidants, vitamins, and minerals that can reduce the look of fine lines and wrinkles, making skin appear younger.

It is critical that you make sunscreen part of your daily skin care regimen. Even if you work in an office all day and spend little time outdoors, your skin will still be exposed to UV radiation as well as other types of light rays.

Wireless devices have become a part of our daily life and work. As someone who uses them professionally, I decided to measure their electromagnetic radiation to see if they are a threat to my health. The results may be interesting to you.

No, this is not an article for the fifth generation mobile communication standard. In this text, you will learn about the amount of radiation emitted from devices such as wireless routers, smartphones, dumb phones, Bluetooth keyboards and mice, laptops, radio triggers for strobes, tablets, and other equipment.

The term "radiation" has gained quite a lot of negative fame because of nuclear power plants. Taken out of context, radiation doesn"t mean anything negative unless you know what is emitted. A fire stove radiates heat. In this article, I will call it EMF radiation, which stands for electromagnetic field radiation.

When electric current travels through wires, it generates a magnetic field around them. The antenna is two pieces of wire with running alternating current. Imagine you have a battery and two wires. Connecting each to one of the battery terminals creates a current in one direction and when you switch the plus and minus terminals you reverse the current flow. That"s basically how alternating current works: it switches positive and negative current. On each polarity change, a electromagnetic wave is created just like when you make a wave in a pool of water. The more frequent the changes are, the more waves are generated. The number of polarity switches per second determines the frequency of the waves in units called Hertz (Hz). If you do a manual switch, the frequency will be one or two switches per second or 1-2 Hz. The power cables in your home are running alternating current that is 60 Hz, which means there is a device (generator) that generates current of different polarity 60 times per second.

Can"t we use the 60 Hz power cables to transmit data? Why do we use devices of such a high frequency as the 2.4 GHz router? The answer is: yes, we can use 60 Hz for data transfer, but it will be very slow.

Let"s forget about electronics for a while and pretend we have two people on two mountain peaks that send smoke signals to each other. They have agreed to send a number of smoke signals during each hour of the day. The number of smoke signals determines a letter of the alphabet. For example, from 1 pm until 2 pm, one of them sends three smoke signals. This is the letter "C," being the third letter in the alphabet. During the light part of the day, they can send messages only with dozen letters. They have to wait for the next hour or the next day in order to send the next letter.

That"s how wireless communication works (a very simplified description of frequency modulation or FM). Each wave that is sent contains a small package of information. If we pretend we are sending one letter per electromagnetic wave, this means we can transfer 60 letters per second. Sending the text of this article over a 60 Hz network would last about six minutes, which is very slow for today"s standards. This is why they have decided to raise the number of waves per second in order to send more data in less time, and that"s how we ended up with gigahertz communication.

Electromagnetic radiation is different from nuclear plants" radiation. With a dosimeter, you can measure the radiation of foods, building materials, rocks, etc. The electromagnetic radiation is not measured with those devices, but with specialized EMF meters. They work like radio receivers, which analyze the received electromagnetic waves and display the result from the analysis on the screen. There are cheap meters that have only one antenna (one-axis meters), and in order to show correct results you have to point them in the right direction. They can cost less than $50, but can give quite false results. There are more expensive tools that have three-axis antennas that analyze the signals in 3D space, so you don"t have to point them to a specific direction. That"s the kind of tool I purchased for these tests: Extech 480836.

During the tests, I used both devices I work with and devices I borrowed from friends. The measurements have been provided at spots where the meter gives a zero reading without the device. This helps ensure that the values on the display will be those that are introduced by the tested equipment. The photos have been made with a DSLR without any wireless activity.

The EMF meter is designed to measure high frequencies, which means the magnetic fields" radiation from the power cables are filtered away. The meter is factory calibrated to show an alarm above 0.4 uW/cm^2. We will talk more about the effect from different values and the established standards further on in the article. For now, keep in mind that most of these devices are set to warn you when they reach levels above 0.4 uW/cm^2.

Fewer and fewer people today use desktop machines. Those that do are aware of the power per dollar advantage, but many others swap the power for mobility by using a laptop, especially with the function for Wi-Fi connectivity. Wi-Fi and Bluetooth are almost identical technologies (from a radio frequency standpoint), because they work in the 2.4 GHz range, but they differ in their power consumption and protocol of communication. Bluetooth is used for close-range devices (wireless mice, keyboards, graphic tablets, smart watches, communication of your phone with your car). Wi-Fi is used for connection with devices that are farther away. For that reason, Wi-Fi consumes more power and drains your battery faster.

The meter shows a value between 4 and 6 uW/cm^2 with occasional peaks up to 13-15 uW/cm^2 on the device. The more internet-heavy the operation is, the more radiation is emitted.

The radiation gets weaker the same way as light: by the inverse square law. This means that by doubling the distance from the source, the radiation gets four times weaker. A laptop with Wi-Fi and active internet use has about 1.5 - 2.2 uW/cm^2 radiation about four inches from it. About a hand distance (two feet), where your head is, the radiation is between 0.4 and 1.0 uW/cm^2.