This was the best vegan EMR-blocking phone case .... I need to carry two IDs and four cards plus cash.. This was too much, so it started to split within months. Eventually it split to the point where my cards would all fall out if I tipped it the wrong way, so I had to put a rubber band on it. After that, the part that holds the phone started to slip so I have to jam it up before I can take a picture. And the case is looking worn. The upshot is that it lasted about a year. That's fine, I guess, but I would prefer something more durable.

First, you must have a proper meter. To check for magnetic field emissions, an AC Gaussmeter will work. Most AC gaussmeters will have an internal probe. Simply position the gaussmeter on the phone. Note carefully where the meter is positioned. Make a call and watch the readings. Notice the highest and lowest readings, and make a mental note of the "average" reading. Now, insert the magnetic shield, and repeat.

Manufacturers conduct government-required certification tests using a bare phone, set to transmit at maximum power, with no accessories. The recorded maximum SAR is reported to the FCC and listed in the phone’s manual. A phone tested with accessories under the same conditions can produce a higher SAR because the materials surrounding the antenna can affect the amount of radiation that reaches and is absorbed by the user’s body. A case can influence both the overall amount of emitted radiation and how it is directed.

Pong’s research indicates that badly designed cell phone cases can partially block a phone’s antenna, making the device work harder to transmit signals. Due to gaps in the FCC’s cell phone regulations, a phone worn right next to the body and enclosed by a case that obstructs the antenna could expose the user to more radiation than the FCC’s legal limit.
Dr. Carlo, however, refused to be an easy target. He quickly recruited a group of prominent scientists to work with him, bulletproof experts owning long lists of credentials and reputations that would negate any perception that the research was predestined to be a sham. He also created a Peer Review Board chaired by Harvard University School of Public Health’s Dr. John Graham, something that made FDA officials more comfortable since, at the time, the agency was making negative headlines due to the breast implant controversy. In total, more than 200 doctors and scientists were involved in the project.
A large prospective (forward-looking) study of nearly 800,000 women in the UK examined the risk of developing brain tumors over a 7-year period in relation to self-reported cell phone use at the start of the study. This study found no link between cell phone use and brain tumors overall or several common brain tumor subtypes, but it did find a possible link between long-term cell phone use and acoustic neuromas.
EWG is calling on the FCC to update its testing guidelines to take account of the widespread use of smartphone cases. Such action is critical because mounting scientific studies have raised serious questions about the safety of cell phone radiation exposure over the short and long term. In the absence of meaningful action by the Commission, EWG offers consumers tips on how to reduce their exposure to cell phone radiation.
“When symptoms are not addressed comprehensively– for example, using symptom amelioration without simultaneous elimination of exposure – cell membrane adverse reaction and damage continue to occur while the patient is assuming the cause of the problem has been eliminated. This lulls patients into a false sense of security, causing them to aggravate their exposures through the increased use of their wireless devices. When the damage reaches a critically harmful level, even the symptom amelioration can no longer be sustained by the damaged cells.”
Wherever you come out on the cellphone and cancer question, one thing is clear: How we live with cellphones, along with our exposure to the radiation they emit, has changed dramatically over the past several decades. That has policy implications; it’s something regulators, researchers, and cellphone companies need to pay attention to. In that context, a few things should happen:

Parents and consumer advocacy groups occasionally capture attention for voicing concerns about cellphones and other types of non-ionizing radio-frequency radiation exposure, such as the energy emitted from wifi routers in schools. In some cases, they have exaggerated what we know about the risks to kids, and rarely note that cellphones are also just one of many radiation sources we all live with. (Even the Earth itself, the air we breathe, and the sun and stars in our galaxy constantly give off radiation.)
These expert committees determined that there are indeed gaps in the knowledge concerning the implications of exposure to this radiation, and therefore they called for further studies on the subjects and recommended to adopt the “precautionary principle". This principle adopts simple and relatively cheap means to reduce exposure to the minimum radiation levels possible with existing technology.

Researchers have carried out several types of epidemiologic studies in humans to investigate the possibility of a relationship between cell phone use and the risk of malignant (cancerous) brain tumors, such as gliomas, as well as benign (noncancerous) tumors, such as acoustic neuroma (tumors in the cells of the nerve responsible for hearing that are also known as vestibular schwannomas), meningiomas (usually benign tumors in the membranes that cover and protect the brain and spinal cord), and parotid gland tumors (tumors in the salivary glands) (3).