The harm from the use of mobile phones and smartphones has not yet been fully proven, sometimes we hear the results of “shocking” research, but they are more similar to the revelations from psychics show than to trying to force us not to use such gadgets.
The opinion that phones are harmful is fixed in the world information field, but the danger from their use is so small that you can ignore it.
Every year at the presentation of the new Apple smartphone, we hear hundreds of emails, praises of the new camera and endless comparisons of the device’s power with previous models. Behind the squall of information about megapixels and gigabytes hide one of the important indicators of iPhones – SAR .
What is SAR
SAR (Specific Absorption Rate) is the specific absorption coefficient of electromagnetic energy by the tissues of the human body in one second. This indicator measures the magnitude of the harmful effects of a mobile phone on the user.
SAR is measured in watts per kilogram or per square centimeter.
In Europe, the maximum allowable radiation value is 2 W / kg for 10 grams of tissue. In the US, the Federal Communications Agency certifies only those cellular devices whose SAR is not higher than 1.6 W / kg for 1 gram of tissue.
In Russia, a different system for measuring radiated power is in watts per square centimeter. It is rather difficult to translate the world measurement systems to the domestic one; it can be done only by experience.
What is harmful impact of the phone
The human body on average consists of 70% of water, the molecules of which are able to absorb the energy of high-frequency radiation and convert it into thermal energy. In other words, the phone’s radiation can heat the water molecules in our body just as a microwave oven heats food.
The temperature of the tissues of the human brain in the process of vital activity can change the temperature by 1 degree Celsius without consequences. Greater temperature fluctuations adversely affect human health.
If we consider, for example, the European SAR rate, then at the maximum safe level of radiation of 2 W / kg, the temperature in the tissues may increase by approximately 0.3-0.5 degrees Celsius. In theory, this does not harm the body, however, in combination with other types of electromagnetic effects, it can lead to irreversible consequences.
With such a change in temperature, the destruction of protein chains is often found, and scientists have not yet come to a common opinion regarding the effect of this fact on health.
How to check the real SAR device
There are several special centers around the world for radiation safety checks and electronic device certification. One of the most technologically advanced is the STUK radiation and nuclear safety center in Finland.
A special form is filled with a substance that is similar in its properties to the tissues of the human body. The radiation source is placed in close proximity to the form, and then the radiation level is measured at various operating modes of the gadget.
Here is the SAR measurement process:
We return to the iPhone
Here is the comparative table of SAR levels for all iPhone models in the US measurement system:
As you can see, the SAR figures are far from the maximum allowable 1.6 W / kg for 1 gram of tissue, but the new iPhone 7 is the most “harmful” in this parameter among current smartphones.
For comparison, the SAR level of the main competitor of the Samsung Galaxy S8 is 1.25 W / kg for the head and 1.52 W / kg for the body.
Should I worry
The specified SAR value is determined when the phone is operating at maximum power. In practice, this occurs infrequently, the level of radiation depends on the quality of the network, terrain and proximity of the towers of the mobile operator.
The radiation level increases with a bad network signal and decreases with a good one. Peak values are recorded during network search and making a call (dialing).
Impact may depend on the position of the phone relative to the head, on the biological characteristics of the body and age.
Studies on the possible effect of radiation from mobile phones on the growth of cancer have not reached unambiguous conclusions. Universal use of phones lasts about 10 years, and much more time is required for accurate analysis.
Do not forget that smoking, the harm of which has long been proven, was even considered useful until the middle of the 20th century.
As a general recommendation, it is worth remembering that the radiation power decreases inversely with the square of the distance. This means that when the radiation source is removed from the body by 2 times, the irradiation decreases by 4 times.