Take a closer look at the product claims. Many refer to their “shielding technology” and not the product itself. In many cases, the “FCC Certified” labs they cite are actually testing how much RF the raw shielding material can block. They’re testing the materials used in the products. They’re not testing how much RF the actual products block while on a real-world phone.

Can cellphone radiation cause cancer in humans? There’s no scientific consensus on this issue, but there is “some evidence” that exposure to radiation equivalent to that emanating from 1990s-era cellphones is associated with brain tumors in male rats, according to results of a US National Toxicology Program (NTP) study released last week (November 1). 
The European Union is currently running the Mobi-Kids, a case-control study in 14 countries, to better understand the effects of electromagnetic fields radiation on children and adolescents. One of the early publications from the project, looking at data on the use of wireless devices among 10- to 25-year-olds in France, found that kids are started to rely on these devices earlier and earlier in life. But the researchers are still analyzing the main results on any health impacts, and haven’t yet published their findings.
In a February 2 statement, Jeffrey Shuren, director of the FDA’s Center for Devices and Radiological Health, wrote that despite the NTP study’s results, the combined evidence on RF exposure and human cancer—which by now amounts to hundreds of studies—has “given us confidence that the current safety limits for cell phone radiation remain acceptable for protecting the public health.” Chonock says that for him, evidence from the Ramazzini study does not alter that conclusion. “We continue to agree with the FDA statement,” he says.
Overall, the reviews of case-control studies seem to suggest there is perhaps no risk of cancer with cellphone use — unless you look at some subgroups (like people in blinded studies or people with long-term exposures). But these reviews are based on case-control studies — which are like the National Enquirer of the science world: cheap and often misleading.
Cellsafe backs its claims by publishing independent test results on its site. These test reports are detailed, complex and confusing, but the results are available for you to interpret. For example, their tests found that an iPhone 4S produced a SAR of 1.069 W/kg on the 3G 2100Mhz frequency without a case, and 0.267 W/kg with a Cellsafe case. But what in the world does that actually mean? Is a SAR of 1 W/kg dangerous? Is a reduction to 0.267 W/kg actually better, or are we just splitting hairs?
 I purchased two different color cases and I was surprised when I received it because the inner case was different than described in some of the reviews. But when I looked at the Amazon listing, I didn’t realize that the case has been updated and I’m pleasantly surprised. The inner case is a soft, flexible plastic that doesn’t seem like it would break at all. I borrowed an EMF reader from a friend and the case works as described. I’m very happy with the cases and I’m glad that I purchased one for my boyfriend too! I definitely recommend this case!

Third, most of the studies published so far have focused on adults, rather than children. (One case-control study looking at children and teens did not find a significant link to brain tumors, but the small size of the study limited its power to detect modest risks.) Cell phone use is now widespread even among younger children. It is possible that if there are health effects, they might be more pronounced in children because their bodies might be more sensitive to RF energy. Another concern is that children’s lifetime exposure to the energy from cell phones will be greater than adults’, who started using them at a later age.
INTEGRITY: Many manufactures claim near 100% EMF protection, referring to the radiation blocking material, NOT the protection you receive on a call. If you covered your whole phone with EMF blocking material, then you'd have no signal. Our EMF blocking material is used on the front cover only, providing you real EMF protection with no sacrifice in reception.
Though some findings were reassuring, others do raise concerns. Specifically, three of the studies—one from Sweden, another from France, and a third that combined data from 13 countries—suggest a connection between heavy cell-phone use and gliomas, tumors that are usually cancerous and often deadly. One of those studies also hinted at a link between cell phones and acoustic neuromas (noncancerous tumors), and two studies hinted at meningiomas, a relatively common but usually not deadly brain tumor.
Okay, so Antenna Search isn't really a device but it is a handy service that will tell you how close you are to cellular towers. I punched in my address and found there are SEVENTY-TWO cellular towers and antennas within a 4 mile radius. It lists all the details for each tower – owner, coordinates, installation date, etc. It's a really useful tool for finding out the surrounding risks.
It also means regulators need to make sure their policies reflect new levels of exposure. The Federal Communications Commission currently oversees cellphone safety and sets the limits for how much radiation people should be exposed to. (This is measured by the specific absorption rate — the rate at which the body absorbs radio frequency energy — and the current limit for cellphones is 1.6 watts of energy per kilogram of tissue. The whole-body threshold is a SAR value of 0.08 watts per kilogram, and the tower radiation limit is 10 watts per square meter.)
Let’s be honest, we’re addicted to our smartphones. According to an ABC news report, the average person checks their phone 150 times per day, not to mention the other 15 hours per day it sits in your pocket. It’s also nothing new that cell phones emit Electromagnetic Fields/Radiation (EMF/EMR) when it’s glued to the side of our head more than 22 times per day. 
There are fears that the electromagnetic radiation emitted from mobile phone handsets may harm health. In particular, there have been claims that it could affect the body’s cells, brain or immune system and increase the risk of developing a range of diseases from cancer to Alzheimer’s. Laboratory tests on mice have shown that radiation from mobile phones can have an adverse effect on their overall health. It is still not clear whether those findings can be applied directly to humans. A study by scientists in Finland, published in 2002, suggested that the electromagnetic radiation did affect human brain tissue. But they played down their findings saying more research was needed to see if the effects were the same in living people. Another study by scientists in Sweden, also published in 2002, claimed to have found a link between analogue mobile phones and brain tumours. It suggested users of “first generation” phones had a 30% higher risk of developing tumours than people who did not. However, the findings were controversial and there have been no similar studies into the effects of modern GSM phones. There have also been reports of people suffering from headaches, fatigue and loss of concentration after using their mobile phones. However, these claims have not been scientifically substantiated.
Until the FCC establishes testing procedures that fully correspond to real-world cell phone use and reviews its radiation standards to ensure that they are fully protective for all users, including young children, EWG advises phone users to adopt these simple measures to minimize radiation exposure: Use a headset, keep the phone away from the body and text rather than talk.  
I really want to caution you to be careful of any "expert" or EMF blogger recommending anti-radiation filtering cases, stickers that attach to the phone or necklaces to "ward off" EMF.  I get it, when I first realized 25 years ago that I was sensitive to electromagnetic energy and then later, when I understood that without a doubt, man made electromagnetic radiation has a biological effect on my body, I wanted an easy fix.  I tried the shielding materials and cases and I just did not feel any better.  Then I bought meters to see if the energy changed and I actually noticed what the California Department of Health now says and it's what the FTC and FCC post warnings about:  "Some shielding materials can make exposures worse". So please, be careful and read on for what you can do to avoid electromagnetic radiation exposure.

Says Dr. Carlo: “We also conducted four different epidemiological studies on groups of people who used cell phones, and we did clinical intervention studies. For example, studies of people with implanted cardiac pacemakers were instrumental in our making recommendations to prevent interference between cell phones and pacemakers. In all, we conducted more than fifty studies that were peer-reviewed and published in a number of medical and scientific journals.”
Protect your brain from RF (radio-frequency) pollution with this handsome baseball style hat. Specially designed to shield the head from frequencies from below AM through microwave, including cellular phone frequencies. Lined with sophisticated Staticot fabric woven from ployester/cotton with an ultrathin stainless steel fibers excellent radiation protection. This gives this unique fabric a truly comfortable, natural feel and the durability and washability of cotton, but with exceptional reflective characteristics.
The government, however, does not require phone manufacturers to consider the effect of cases when they conduct compliance tests to meet the FCC’s allowable radiation exposure limits. The significance of this omission was underscored by tests commissioned by case-maker Pong Research and submitted to the FCC in May 2012. Those tests showed that three models of cases made by competing companies and used with an iPhone4 increased the phones’ Specific Absorption Rate, or SAR – the amount of radiation absorbed by the user’s body – by 20-to-70 percent (Table 1).
(Some common flaws in these studies: The summaries of the evidence weren’t comprehensive, the researchers often didn’t look at the quality of the studies they found, and they failed to do other simple things that would limit bias from creeping in. They also relied on case-control studies, a poor method to determine causality — more on that soon.) So we didn’t include these eight reviews in our analysis.
Let’s say you are in class, or at the movies, and you don’t want your phone to ring. Slip it into the fully shielded slot. In this position, RF signals in or out will be reduced almost to zero, which is enough to stop the phone from ringing in most circumstances unless you have an especially good connection. You can also store chipped cards (like credit cards) in here to prevent unintentional reading.
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According to the WHO, the "precautionary principle" is "a risk management policy applied in circumstances with a high degree of scientific uncertainty, reflecting the need to take action for a potentially serious risk without awaiting the results of scientific research." Other less stringent recommended approaches are prudent avoidance principle and as low as reasonably practicable. Although all of these are problematic in application, due to the widespread use and economic importance of wireless telecommunication systems in modern civilization, there is an increased popularity of such measures in the general public, though also evidence that such approaches may increase concern.[35] They involve recommendations such as the minimization of cellphone usage, the limitation of use by at-risk population (such as children), the adoption of cellphones and microcells with as low as reasonably practicable levels of radiation, the wider use of hands-free and earphone technologies such as Bluetooth headsets, the adoption of maximal standards of exposure, RF field intensity and distance of base stations antennas from human habitations, and so forth.[citation needed] Overall, public information remains a challenge as various health consequences are evoked in the literature and by the media, putting populations under chronic exposure to potentially worrying information.[36]
California officials issued the new report in response to increasing smartphone use in the United States, especially among children. About 95% of Americans own a cell phone, according to a press release from the California Department of Public Health, and the average age for a first cell phone is now 10 years old. About 12% of people use their smartphones for daily Internet access.
The International Agency for Research on Cancer (IARC) is part of the World Health Organization (WHO). Its major goal is to identify causes of cancer. The IARC has classified RF fields as “possibly carcinogenic to humans,” based on limited evidence of a possible increase in risk for brain tumors among cell phone users, and inadequate evidence for other types of cancer. (For more information on the IARC classification system, see Known and Probable Human Carcinogens.)

The only consistently recognized biological effect of radiofrequency radiation in humans is heating. The ability of microwave ovens to heat food is one example of this effect of radiofrequency radiation. Radiofrequency exposure from cell phone use does cause heating to the area of the body where a cell phone or other device is held (e.g., the ear and head). However, it is not sufficient to measurably increase body temperature. There are no other clearly established effects on the human body from radiofrequency radiation.