If not, then how can the seller claim that the reported effects on cell cultures, muscle strength testing, plants, skin heating, or other biological effects are due to electromagnetic changes (see http://www.cellphone-health.com/mret-howitworks.htm for example)? Electromagnetic field characteristics are well known and easy to measure. If there is truly an electromagnetic change, that change will be easy to detect and measure.

Use the speaker mode on the phone or a hands-free device such as a corded or cordless earpiece. This moves the antenna away from your head, which decreases the amount of RF waves that reach the head. Corded earpieces emit virtually no RF waves (although the phone itself still emits small amounts of RF waves that can reach parts of the body if close enough, such as on the waist or in a pocket). Bluetooth® earpieces have an SAR value of around 0.001 watts/kg (less than one thousandth the SAR limit for cell phones as set by the FDA and FCC).
The outside is made of a synthetic polyurethane that feels just like leather, although genuine leather will be available soon. The inside is made of a microfiber that won’t scratch the phone. The materials are also designed to protect your phone, should you drop it. Most importantly, an integrated FCC-certified lab tested radiation-shielding foil not only deflects and absorbs RF, ELF and Thermal radiation to greatly reduce your exposure, but it also blocks RFID signals, so that hackers cannot steal your credit card information by scanning it from afar. And no, the case will not affect phone or battery performance.
It’s easy to call any case a product designed to block smartphone radiation.  What you need to look for is credible, quantifiable claims that highlight a case’s ability to reduce your exposure to the harmful radiation. Look for relevant  certifications from credible organizations (such as FCC accredited laboratories) that will vouch for product claims, and read product reviews online.
The city council of Berkeley, Calif., has also acted. In May 2015, it approved a “Right to Know” law that requires electronics retailers to notify consumers about the proper handling of cell phones. CTIA-The Wireless Association, a trade group, is now trying to block that law from going into effect, as it successfully did after San Francisco passed its own Right to Know law five years ago.
A recent large study by the US National Toxicology Program (NTP) exposed large groups of lab rats and mice to RF energy over their entire bodies for about 9 hours a day, starting before birth and continuing for up to 2 years (which is the equivalent of about 70 years for humans, according to NTP scientists). The study found an increased risk of tumors called malignant schwannomas of the heart in male rats exposed to RF radiation, as well as possible increased risks of certain types of tumors in the brain and adrenal glands. But some aspects of this study make it hard to know just how well these results might be applied to cell phone use in people. For example, there was no clear increased risk among female rats or among male or female mice in the study. The doses of RF radiation in the study were also generally higher than those used in cell phones (ranging from 1.5 W/kg to 6 W/kg in rats, and 2.5 W/kg to 10 W/kg in mice), the animals’ entire bodies were exposed, and the amount of time they were exposed was longer than most people typically spend on the phone each day. The male rats in the study exposed to RF waves also lived longer, on average, than the rats who were not exposed, for unclear reasons. Because of this, the NTP has noted that the study results cannot be directly applied to humans. Still, the results add to the evidence that cell phone signals might potentially impact human health.
“One thing all these conditions have in common is a disruption, to varying degrees, of intercellular communication. When we were growing up, TV antennas were on top of our houses and such waves were up in the sky. Cell phones and Wi-Fi have brought those things down to the street, integrated them into the environment, and that’s absolutely new. The recognition mechanism, where protein vibration sensors on the cell membrane pick up a signal and interpret it as an invader, only works because the body recognizes something it’s never seen before.”
In one type of study, called a case–control study, cell phone use is compared between people with these types of tumors and people without them. In another type of study, called a cohort study, a large group of people who do not have cancer at study entry is followed over time and the rate of these tumors in people who did and didn’t use cell phones is compared. Cancer incidence data can also be analyzed over time to see if the rates of brain tumors changed in large populations during the time that cell phone use increased dramatically. These studies have not shown clear evidence of a relationship between cell phone use and cancer. However, researchers have reported some statistically significant associations for certain subgroups of people.
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