Stick on anti-radiation protection shields etc are often made of metal which may block signal and prevent reliable mobile phone communications with signal towers. Mobile phones recognise the potential for a dropped signal and actually increase power to compensate. The result is a fast draining battery and an even higher radiation output as a result of using the product (an exception to this are shields that are placed in between the phone and the user as these do not impede signal to cell towers to any significant degree)
Our tests wre conducted with three RF meters, set at fixed position next to the iPhone. Our primary meter was the Gigahertz Solutions HFE 59B, a professional RF instrument. We also used a TES 593 (Mid-Range Consumer Grade Instrument) and the Acousticom 2 (Low-Range Consumer Grade Instrument) to compare/confirm the increases and decreases in RF and for visual reference.
We’ll see how it holds up, but out of the box this case is wonderful. No problems at all with it interfering with the cameras or the four microphones in the iPhone 7. In fact, my last case must have interfered with the mics because people I call often are now saying the sound is much better on their end, and this is when the case is closed with speakerphone on. // This case is put together nicely. Good stitching, nice texture. I am a vegan so I feel good using it. // I haven’t used the card or money slots so I can’t speak about those. It’s not important to me anyway. // All-in-all I’m very pleased. I was a little apprehensive spending $35 or whatever amount it was, but this case is quality. Hope it blocks the bad stuff like they say it does. I feel the company is very straightforward and honest in their product information and didn’t make outlandish claims. Great case! // Update, 5 months later. Perfect. Not a stitch broken. It’s holding up extremely well. Very pleased.
Some scientists have reported that the RF waves from cell phones produce effects in human cells (in lab dishes) that might possibly help tumors grow. However, several studies in rats and mice have looked at whether RF energy might promote the development of tumors caused by other known carcinogens (cancer-causing agents). These studies did not find evidence of tumor promotion.
But according to the FCC, comparing SAR values between phones can be misleading. The listed SAR value is based only on the phone operating at its highest power, not on what users would typically be exposed to with normal phone use. The actual SAR value during use varies based on a number of factors, so it’s possible that a phone with a lower listed SAR value might actually expose a person to more RF energy than one with a higher listed SAR value in some cases.
Some products (http://www.safecell.net/reports01.html for example) are tested using a piece of shielding material in a laboratory test jig. These tests legitimately show the amount of radiation which penetrates the shield, but results will be very different when compared to putting a small amount of the same shield on a large transmitter like a cellphone. Remember, the entire phone radiates. Placing a small amount of shielding, even if it is an effective shielding material, only shields that small area at best. Think about this analogy: no light will penetrate a penny as it is a very effective light shield, but it is silly to think that holding a penny up to the sun will put you in darkness.
Radiofrequency radiation is a form of electromagnetic radiation. Electromagnetic radiation can be categorized into two types: ionizing (e.g., x-rays, radon, and cosmic rays) and non-ionizing (e.g., radiofrequency and extremely low frequency, or power frequency). Electromagnetic radiation is defined according to its wavelength and frequency, which is the number of cycles of a wave that pass a reference point per second. Electromagnetic frequencies are described in units called hertz (Hz).