So for example, if you have a Samsung Galaxy S 5 you could turn it off completely (briefly pulling the battery if you need to) push the power button to turn the phone back on until you see the Samsung Galaxy S5 logo screen, release the power button and then immediately press and hold the Volume Down key until the phone booted up with Safe Mode activated displaying “Safe mode” in the bottom left hand corner of the phones display.
These articles and websites don’t exist because the threat is real, however. They exist because they are a vehicle for turning people’s fear into money. The more people share nonsense articles about the dangers of Wi-Fi (or other harmless modern things) the more people click on them, the more ad-revenue is generated, and the more motivation the people peddling these rubbish articles have to keep creating and promoting them.
The WHO began to study the health effects of electric- and magnetic-field radiation (EMF) in 1996 under the direction of Michael Repacholi, an Australian biophysicist. Although Repacholi claimed on disclosure forms that he was “independent” of corporate influence, in fact Motorola had funded his research: While Repacholi was director of the WHO’s EMF program, Motorola paid $50,000 a year to his former employer, the Royal Adelaide Hospital, which then transferred the money to the WHO program. When journalists exposed the payments, Repacholi denied that there was anything untoward about them because Motorola had not paid him personally. Eventually, Motorola’s payments were bundled with other industry contributions and funneled through the Mobile and Wireless Forum, a trade association that gave the WHO’s program $150,000 annually. In 1999, Repacholi helped engineer a WHO statement that “EMF exposures below the limits recommended in international guidelines do not appear to have any known consequence on health.”34

To date, there are a few long-term studies, very few in humans and even fewer epidemiological studies, apart from the studies on laptops with small numbers of study subjects. It is also far too early to generate reliable figures at this time. However, there are indications that especially newborns, children, or adolescents are particularly vulnerable as has been presented in detail by the research teams of Nazırogˇ lu, Atasoy, Margaritis/ Panagopoulos, Orendacˇ ova, Othmann, Ozorak, Sangun, Shahin and Yuksel. The experiments were carried out with rats or mice, in some cases as long-term studies (up to 1 year). In this context, it is important to note that rats and mice used in laboratories have a life expectancy of perhaps two years. This at least allows us to infer that human children and adolescents have to be protected from possible increased risks. In the study of Margaritis et al. (2014), the authors point out that the exposure levels from Bluetooth (0.3 V/m) and Wi-Fi routers (here 2.1 V/m) showed greater effects than cell phone radiation sources with much higher field strengths. This may coincide with the findings of the papers by von Klitzing, which stated that the power-dependent pulse of 10 Hz (1 ms) from Wi-Fi routers triggered reactions. Kumari et al. observed in a study from 2012 that higher levels of ROS in the liver suppress antioxidant enzymes and that lower levels cause an increase. This could be a key to further mechanisms as to how or whether tissue damage occurs or perhaps not. Likewise, the polarization of RF radiation (Meena et al. 2014, Panagopoulos et al. 2015) should also receive additional attention.
46. Tape your home number on your phone (or a parent’s cell phone number). “Imagine your child’s phone (or your own) is lost. Even if the person who finds it wants to return it, they have to go through your private information to find a number to dial. Make it easy. Tape your home number (or whatever number is suitable) to the back of the phone, along with information about a reward, if you like. That way, even with a password locking the keypad or screen, a do-gooder can get you your phone back!” – marianmerritt, Cell Phone Safety Tips for Kids, Norton Community by Symantec; Twitter: @NortonSupport
Ionizing radiation, including x-rays and ultraviolet light, produces molecules called ions that have either too many or too few electrons. Ions are known to damage DNA and cause cancer. Cell phone radiation, like radio, TV, and visible light radiation, is non-ionizing and lacks sufficient energy to add or remove electrons from molecules, and therefore it cannot ionize and cause cancer. [2] According to the authors of a 2005 peer-reviewed study of 3.7 million Swedish residents, a "biologic mechanism that could explain any possible carcinogenic effect from radiofrequency radiation has not been identified." [42]

It should be noted that the given values of SAR were normalized to 1 W peak antenna power output, while typically a WLAN antenna radiates about 10 mW; therefore, for a real world operating system, maximum SAR of 0.37 × 10−3 and 0.18 × 10−3 (W/kg) is expected for 2 and 1 active antennas, respectively, which are 104 times lower than the European safety limit (2 W/kg) [IEEE Standard for Safety Levels with Respect to Humans, 2005].

MATERIAL AND METHODS: 70 male Wistar rats weighing 200-250 g were randomly divided into 7 groups (10 rats in each group).The first stage one-day test: Group A (received vitamin C 250 mg/kg/day orally together with 8- hour/day Wi-Fi exposure). Group B (exposed to Wi-Fi radiation). Group C (received vitamin C). Group D or Control (was neither exposed to radiation of Wi-Fi modem nor did receive vitamin C). The second phase of experiment had done for five consecutive days. It involved Group E (received vitamin C), Group F (exposed to Wi-Fi radiation), Group G (received vitamin C together with Wi-Fi radiation). The distance between animals' restrainers was 20 cm away from the router antenna. Finally, blood samples were collected and assayed the level of hepatic enzymes including alkaline phosphatase (ALP), alanine amino transferase (ALT) aspartate amino transferase (ASL), gamma glutamyl transferase (GGT) and the concentration of Blood Glucose, Cholesterol, Triglyceride (TG), High density lipoprotein (HDL) and low density lipoprotein (LDL).

If you are concerned about the possible health effects of radio wave radiation emitted by your cell phone, your options are simple and cheap. This kind of radiation is at its highest levels nearest the antenna. Also, not all cell phones are created equal. Sar Shield offers a useful radiation chart for cell phones that provides an accurate "Sar rating" for every cell phone model. It's important to realize that at these low radiation levels, if you keep the cell phone away from your head and body, you are perfectly safe. However, if you'd rather not use a headset, then there are plenty of resources to obtain a radiation shield for your phone.
WiFi operates in the 2 to 5 GHz range -- part of the microwave portion of the electromagnetic spectrum. This is in the same part of the spectrum where cell phones operate so I may refer to WiFi or cellphone electromagnetic radiation interchangeably. These are radio waves -- no different from those used to broadcast television programs, except that they are higher in frequency. They aren't nearly as high a frequency as visible light, and no one worries about getting cancer from visible light (ultraviolet light, on the other hand, causes skin cancer, but this is the minimum energy necessary to cause ionizations that can cause breaks in strands of DNA, which is the mechanism by which cancer cells can be created). There is no credible evidence that non-ionizing radiation has any adverse health effects at all. There is no radiobiologic mechanism that could explain such an association -- and absolutely no scientifically valid evidence that this has ever happened.

Since we have this subconscious, ever-present fear of death, we employ magical thinking to give us a false sense of power over it. When we create artificial threats to our survival in our imagination, and then avoid practicing behaviors that make us vulnerable to those threats, we feel we have some power over whether we live or die. These are also known as superstitions.
This is extremely important for a lot of reasons but will be crucial for any step to reducing radiation. Having a quality EMF meter will allow you to determine what kind of radiation devices in your home are emitted, as well as how much. This will also be crucial in understanding how different changes are improving this I would highly recommend either the TriField TF2 (read my review), or Meterk (read my review) if you need a lower cost EMF meter.
Studies have shown an association between cell phone use and a decreased risk of certain brain tumors. According to a peer-reviewed Dec. 2006 study of 420,095 cell phone users in Denmark, the results showed a "reduced brain tumor risk" among long-term subscribers. [1] Two other peer-reviewed studies also found that cell phone users had a slightly decreased risk of developing brain tumors. A July 20, 2005 Danish study [41] found a "decreased risk for high-grade glioma," a malignant brain tumor, and a 2005 Swedish study [42] also found a "decreased odds ratio" for developing glioma as well as meningioma, another type of brain tumor.

Acute exposure of rabbits to WIFI increased heart frequency (+22%) and arterial blood pressure (+14%). Moreover, analysis of ECG revealed that WIFI induced a combined increase of PR and QT intervals. By contrast, the same exposure failed to alter maximum amplitude and P waves. After intravenously injection of dopamine (0.50 ml/kg) and epinephrine (0.50 ml/kg) under acute exposure to RF we found that, WIFI alter catecholamines (dopamine, epinephrine) action on heart variability and blood pressure compared to control. 
In a separate study by the same Swedish team, they found more than seven times the risk among people using a cell phone more than 20 years and 6.5 times the risk for long-term users of cordless phones. As expected, most of the gliomas and acoustic neuromas were on the same side of the head, which was usually exposed to the phone. In the 2013 official report on the medical evidence for brain tumors, the International Agency for Research on Cancer concluded that radiation from cell phones is “possibly carcinogenic to humans”.