So, what types of RF are these cases intended to block? If they block the frequency being used by the phone than if the blocking is complete the phone won’t work. If it’s partial than, as noted by the FCC and related in the article, the phone may attempt to compensate for the weakened signal by increasing it’s signal strength, thereby emitting higher levels of radiation itself, and reducing battery life in the process.

While an increased risk of brain tumours from the use of mobile phones is not established, the increasing use of mobile phones and the lack of data for mobile phone use over time periods longer than 15 years warrant further research of mobile phone use and brain cancer risk. In particular, with the recent popularity of mobile phone use among younger people, potentially longer lifetime of exposure, WHO has promoted further research on this group and is currently assessing the health impact of RF fields on all studied endpoints. A cohort study in Denmark linked billing information from more than 358,000 cell phone subscribers with brain tumour incidence data from the Danish Cancer Registry. The analyses found no association between cell phone use and the incidence of glioma, meningioma, or acoustic neuroma, even among people who had been cell phone subscribers for 13 or more years. (4)

While an increased risk of brain tumours from the use of mobile phones is not established, the increasing use of mobile phones and the lack of data for mobile phone use over time periods longer than 15 years warrant further research of mobile phone use and brain cancer risk. In particular, with the recent popularity of mobile phone use among younger people, potentially longer lifetime of exposure, WHO has promoted further research on this group and is currently assessing the health impact of RF fields on all studied endpoints. A cohort study in Denmark linked billing information from more than 358,000 cell phone subscribers with brain tumour incidence data from the Danish Cancer Registry. The analyses found no association between cell phone use and the incidence of glioma, meningioma, or acoustic neuroma, even among people who had been cell phone subscribers for 13 or more years. (4)
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.

The dangers of driving and texting are old news; if someone were to be harmed by their cellphone’s radiation, though, that would make headlines because novelty grabs people’s attention. In psychological experiments where people have to choose images, they gravitate towards ones they haven’t seen before — a phenomenon known as the novelty bonus. So if I wanted to grab a reader’s attention, I’d bet on a hypothetical headline that said “For the first time, cellphone radiation causes brain cancer in humans” over “Another person has died today from driving and texting.”
The most common effect is heat generation (though non-thermal biological harm has also been demonstrated), which can alter the characteristics of various bodily tissues depending on the amount of radiation present and its ability to penetrate the body. Tissue damage can promote the cellular mutations and increase your long-term risk of developing cancer.
 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!
The government’s policies must change. Cell phone users should make their voices heard to prompt the FCC and manufacturers of cell phones and cases to ensure that these accessories never increase and, to the extent possible, decrease, users’ radiation exposure. At minimum, the FCC must take cell phone cases into consideration when it updates its standards to ensure that the use of a case will not expose people to more radiation than its legal SAR limit.  
Changing technology and methods of use. Older studies evaluated radiofrequency radiation exposure from analog cell phones. Today, cell phones use digital technology, which operates at a different frequency and a lower power level than analog phones. Digital cell phones have been in use for more than two decades in the United States, and cellular technology continues to change (3). Texting and other applications, for example, are common uses of cell phones that do not require bringing the phone close to the head. Furthermore, the use of hands-free technology, such as wired and wireless headsets, is increasing and may reduce exposure by distancing the phone from the body (36, 37).
The 13-country INTERPHONE study, the largest case-control study done to date, looked at cell phone use among more than 5,000 people who developed brain tumors (gliomas or meningiomas) and a similar group of people without tumors. Overall, the study found no link between brain tumor risk and the frequency of calls, longer call time, or cell phone use for 10 or more years. There was a suggestion of a possible increased risk of glioma, and a smaller suggestion of an increased risk of meningioma, in the 10% of people who used their cell phones the most. But this finding was hard to interpret because some people in the study reported implausibly high cell phone use, as well as other issues. The researchers noted that the shortcomings of the study prevented them from drawing any firm conclusions, and that more research was needed.

The World Health Organization states that "A large number of studies have been performed over the last two decades to assess whether mobile phones pose a potential health risk. To date, no adverse health effects have been established as being caused by mobile phone use."[2] In a 2018 statement, the FDA said that "the current safety limits are set to include a 50-fold safety margin from observed effects of radiofrequency energy exposure".[3]
For instance, our tests found that same case in the same location blocked more RF on a Verizon iPhone than it did on an AT&T iPhone. Neuert and other independent EMF experts tell us that was likely due to our proximity to the nearest respective cellphone towers. In a different location, or even facing a different direction, we may have seen different results.
The guidelines created a measure of the rate that body tissue absorbs radiation during cell phone use called the specific absorption rate (SAR). The SAR for cell phone radiation was set at a maximum of 1.6 watts of energy absorbed per kilogram of body weight. The limit was set due to the thermal effects of cell phone radiation (all RF radiation can heat human body tissue at high enough levels) - it was not set to mitigate other biological effects cell phone radiation might have such as DNA damage or cancer.

We couldn't find one legit EMF expert online or anywhere else that would recommend a radiation blocking case or anti-radiation case. Not the Environmental Health Trust or Magda Havas, or Joel Moskowitz, in fact his site, safeEMR cautions against scams and claims for radiation protection.  So if a so-called "EMF expert" is recommending any kind of anti-radiation case, they probably aren't that much of an expert. 
So what do you do when you need a wireless radiation emitting device but you want to limit the exposure to the people? Perhaps you use a wireless baby monitor, have a cordless phone base station, or you sleep with your cell phone on your nightstand. Maybe there is a wifi router right next to you at work or school. RadiaFence is the answer. It’s a free-standing, semi-transparent microwave barrier that you can put almost anywhere you need. It blocks most of the radiation emitted in one direction by “casting a shadow” (typically 70-90% reduction), while still allowing the wireless device to work. Like sitting in the shade on a sunny day. Portable, inexpensive, attractive. And it couldn’t be easier to use. If you like, you can add a decorative photo or warning sign to change the appearance. Available in 5 styles. Pick the sizes which meet your needs. Style may differ from images.
Some studies have found a possible link. For example, several studies published by the same research group in Sweden have reported an increased risk of tumors on the side of the head where the cell phone was held, particularly with 10 or more years of use. It is hard to know what to make of these findings because most studies by other researchers have not had the same results, and there is no overall increase in brain tumors in Sweden during the years that correspond to these reports.
A third requirement was for the FDA to create a formal interagency working group to oversee the work and provide input. The purpose of this was to alleviate any perception that the industry was paying for a result, not for the research itself. But the fourth and last requirement was considered by Dr. Carlo to be highly critical: “Everything needed to be done in sunlight. The media had to have access to everything we did.”
This high quality Blocsock cell phone radiation pouch is made in the UK and is something very special, it has radiation protective material that will cover the whole of the front of your phone whilst you speak and reduce your exposure to harmful cell phone radiation to the brain by 96%. If you want to use a cell phone held to the head this is the only way we know to effectively protect your brain from the two kinds of radiation emitted by your phone. Also you can use the Blocsock to protect your organs if you have to carry a phone on your person

A 2012 study by NCI researchers (25) compared observed glioma incidence rates in U.S. SEER data with rates simulated from the small risks reported in the Interphone study (6) and the greatly increased risk of brain cancer among cell phone users reported in the Swedish pooled analysis (19). The authors concluded that overall, the incidence rates of glioma in the United States did not increase over the study period. They noted that the US rates could be consistent with the small increased risk seen among the subset of heaviest users in the Interphone study. The observed incidence trends were inconsistent with the high risks reported in the Swedish pooled study. These findings suggest that the increased risks observed in the Swedish study are not reflected in U.S. incidence trends.
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