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.

A decline in male sperm quality has been observed over several decades.[11][12][13] Studies on the impact of mobile radiation on male fertility are conflicting, and the effects of the radiofrequency electromagnetic radiation (RF-EMR) emitted by these devices on the reproductive systems are currently under active debate.[14][15][16][17] A 2012 review concluded that "together, the results of these studies have shown that RF-EMR decreases sperm count and motility and increases oxidative stress".[18][19] A 2017 study of 153 men that attended an academic fertility clinic in Boston, Massachusetts found that self-reported mobile phone use was not related to semen quality, and that carrying a mobile phone in the pants pocket was not related to semen quality.[20]
Anti-radiation or radiation blocking or phone shield cases. Do they Work? SafeSleeve, DefenderShield, Vest, Alara, Pong, Reach and ShieldMe  and other EMF protection phone cases claim to block the radiation from your cellphone or smartphone. Anti-radiation cellphone case brands make enticing claims like this: ". . .eliminate up to 99% of the harmful radiation coming from the phone!"
He believes the FDA should put out guidance based on the results of the rat studies. “I would think it would be irresponsible to not put out indications to the public,” Melnick says. “Maintain a distance from this device from your children. Don’t sleep with your phone near your head. Use wired headsets. This would be something that the agencies could do right now.”

When called to help with the cell phone issue, Dr. Carlo was working with the FDA on silicone breast implant research. The choice of Dr. Carlo to head WTR seemed unusual to industry observers. An epidemiologist whose expertise was in public health and how epidemic diseases affect the population, he appeared to lack any experience in researching the effects of EMR on human biology. Based on this, a premature conclusion was drawn by many: Dr. Carlo was an “expert” handpicked by the cell phone industry, and therefore his conclusions would only back up the industry’s claim that cell phones are safe.

Thus far, the data from studies in children with cancer do not support this theory. The first published analysis came from a large case–control study called CEFALO, which was conducted in Denmark, Sweden, Norway, and Switzerland. The study included children who were diagnosed with brain tumors between 2004 and 2008, when their ages ranged from 7 to 19 years. Researchers did not find an association between cell phone use and brain tumor risk either by time since initiation of use, amount of use, or by the location of the tumor (21).
I don’t understand why only the lab tests are accurate. I just purchases two SafeSleeve cases and tested them myself with the same meter they use on their website in the promotional video. I made sure there were no other electronics nearby and I had the meter at zero without the cell phone next to it. I did not get the results they show in the video. I tested the phone with and without the case and it did not make any difference. The meter was peaking no mater what, with the flap opened or closed. If the meter is picking up radiation through the case, then my head is too. SafeSleeve is willing to reimburse me for the cases, but I am concerned that this might be a case of false advertising.

Homeopathic remedies, credit cards and passports with chips, and electronic equipment can all be compromised by exposure to electromagnetic fields. The EMP Can™ is a great air-tight way to store these items and protect them from outside EMF influences including low grade EMP. Shields both radiofrequency and magnetic fields by 95% or more. All metal construction, nice wide mouth and quick-close latch keep contents secure.
“This means we’re on the beginning curve of an epidemic, with epidemic defined as a change in the occurrence of a disease that is so dramatic in its increase that it portends serious public health consequences,” says Dr. Carlo. “This is what’s not being told to the public. One of the things that I suggest to people who use a cell phone is to use an air tube headset. If you use a wired headset, the current moving through the wire of the headset attracts ambient informational carrying radio waves and thereby increases your exposure.”
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).