Wireless computer networks and wireless computers in schools
The education system in Israel has taken many steps in recent years to adapt itself to the twenty-first century.
Although the world has changed beyond recognition in the past hundred years, the education system in Israel remains, more or less, the same system and the teaching method remains the same.
One of these steps is the introduction of computing to schools, classrooms and integrating it into the teaching method.
In the eyes of many, progress is computing. In recent years, wireless computers have been distributed to teachers and infrastructures of wired network, wireless network, projectors, sound systems and smart boards have been deployed in classrooms, which are in schools.
In the last year, the Ministry of Education began distributing wireless laptops to students in some schools, either as a personal computer for each student or as part of a mobile laboratory, that is, a limited number of computers that are integrated into some of the lessons, distributed to the students (every few students get a computer) at the beginning of the lesson and returned at the end of the lesson.
In this article, we will not go into the consequences of using computers on the way of studying, attention and concentration disorder and other pedagogical problems derived from the use of computing itself. In this article we will concentrate on the effects of radiation from computing.
A computer is progress, a wireless computer is radiation
The use of the laptops is done wirelessly. Wireless routers have been installed and are being installed in the schools and transmit regularly, throughout the school grounds.
This transmission is actually multi-frequency radio radiation from multiple sources. When the computers are turned on, wirelessly, another 30 radiation sources are added in each classroom. Each wireless computer itself transmits control signals and information over the wireless network.
When the wireless routers and computers are turned on, a larger portion of the bandwidth is used, the transmission from the computers and routers takes up a larger portion of the frequencies assigned to wireless communication, and the radiation levels increase both on the frequency axis and on the time axis.
The situation at school
Even without the introduction of routers and wireless computers into schools, every classroom today has sources of radio radiation (cellular-radio-wireless) and low-frequency radiation (from the power grid). In every classroom there is radiation from cellular antennas entering through the windows, cellular radiation from the teachers’ and children’s cell phones (today most children have smart phones that transmit even when they are not talking on them to allow data traffic for emails, applications, downloading files, games, etc.), and low frequency radiation from the electrical systems at school (electrical panels, central transformers, high voltage lines and more). Now, in addition to all these sources of radiation, the radiation from wireless routers and computers is added.
Inter-ministerial document
In 2011, an inter-ministerial document was published, which should deal with radiation problems in schools. The document is the result of joint work by representatives from the Ministry of Education, the Ministry of Health and the Ministry of Environmental Protection. In the document it is specified that the use of cell phones by students while at school will be prohibited, landline phones will be banned for students and that areas will be assigned where cell phones can be used only during breaks. All this to reduce the students’ exposure to radiation from these mobile devices. It should be noted that, as far as we know, until this writing, these recommendations are only partially implemented. Regarding low-frequency radiation from the electrical systems, the document establishes steps and ways to measure and reduce the student’s exposure to this radiation.
Regarding the use of wireless routers and computers, the document recommends the use of a wired network and wired computers, but allows the use of wireless only when the use of wires poses a safety hazard and provided that permission has been obtained for this by a safety supervisor and radiation tests have been performed before and after installation. This opening is being used by officials in the Ministry of Education, who started – before the document was written – deploying wireless networks and distributing wireless computers in schools, and continue this action even after the document was submitted.
Appeal to the High Court
Attorney Michael Bach, who represents the national parents’ organization, the Forum for Sane Cell Phones, and attorney Dafna Tahobar (radiation-sensitive and public activist in the field) submitted a petition to the High Court of Justice on the issue before the beginning of the 2012-2013 school year. The petitioners claim that there is no prohibition against the installation and use of a wired computer network and that an office The education recommends a wired network and deploys routers and wireless computers in the field.
CEO circular 10/2012
The circular of the director general of the Ministry of Education published in 10/2012 (after the appeal to the High Court) reiterates the principles formulated in the inter-ministerial document, and yet, the deployment of routers and wireless computers continues.
The WIFI signal
The WIFI signal is very complex and similar, in some ways, to the UMTS signal of third generation cellular communication. The signal consists of several transmissions at adjacent frequencies, with each transmission being called a “channel”. Digital information is broadcast on each channel according to demand. The information is distributed and broadcast in some channels in a parallel manner. Every wireless computer and every wireless router knows how to assemble the parallel information received from all the channels in which there is a transmission, into one sequential information that can be used.
The division of the information into parallel information on the frequency axis, is intended first and foremost to increase the bandwidth of the wireless communication.
The rate of change of the WIFI signal is very fast. These factors make it difficult to measure the radiation of a WIFI signal.
Difficulty measuring WIFI signal
Measuring radiation that changes rapidly and is transmitted in multiple frequencies from many sources, as is done in a classroom where there is a wireless router and wireless computers, by radiation meters approved by the Ministry of Environmental Protection is only partial because the radiation meters are too slow and are not able to correctly summarize the parallel transmission, which is spread over several channels, in the frequency range of 2.4 GHz and 5 GHz which changes rapidly and is transmitted from dozens of radiation sources simultaneously.
Radiation measurement by a standard radiation meter will therefore show only a partial and non-representative result.
To correctly measure this signal, a fast frequency analyzer must be used and the radiation intensities in all transmitted channels must be summed.
The measurement must be done at dozens of measurement points across the classroom and especially in the places where students and teachers sit.
The measurements must be done in a variety of network and computer use descriptors including intentional loading of the network under extreme conditions of data traffic. None of this is done today in radiation tests in schools and is not part of the measurement protocol of the Ministry of Environmental Protection. Therefore, any radiation measurement done today in schools with wireless routers and computers is partial and not representative.
Chronic forced exposure
The exposure of the students, teaching staff and employees to radiation or other pollutants in the schools is forced exposure by virtue of the Compulsory Education Law. Students who do not want to be exposed to radiation cannot avoid exposure when wireless routers are installed at school and laptops are distributed, and they will be exposed to radiation even if they do not participate in the computer classes. In fact, the students, the teaching staff and the workers are exposed to this radiation as soon as they enter the school premises.
But are they exposed at home too?!
Using a wireless router, computers and wireless equipment at home exposes the household members to non-ionizing radiation. Exposure to WIFI radiation at home is different from exposure at school because it is usually smaller and not forced.
Exposure at home is from one wireless router, for home use, and from a small number of wireless computers, usually a single computer. There is of course exposure to radiation from the routers, wireless computers and other wireless equipment of the neighbors, but it is several orders of magnitude lower than the exposure from the router and wireless computers in the apartment itself. This is because block and concrete walls stop some of the radio radiation and because of the distance from the neighbors’ wireless equipment. The school uses professional routers and the number of computers in the same room where the students are is large.
Also, in the home space the exposure is not forced, but voluntary.
The user can even take steps to reduce exposure, which are not possible at school, such as using a wired network, turning on the wireless network only when necessary, stopping the use of wireless phones and using only landline phones. Parents and children who wish to do so will be able to reduce their home exposure to radio radiation to zero, but will not be able to do so in the school area.
The situation in the world
Around the world, wireless routers and computers have been deployed in the schools of England, Canada, the USA and other countries. Every day the testimonies of students about headaches, difficulty concentrating, dizziness and other symptoms of exposure to low levels of non-ionizing radiation are increasing. Particularly striking are the testimonies from Canada, which have been uploaded to the web As a video (see the links at the end of the article), there also arose opposition from parents to the deployment of WIFI in schools.
In England, the head of the teachers’ organization came out publicly against the deployment and use of WIFI in schools. A number of schools in Canada and England stopped using WIFI, and in Switzerland the state published an outline in which a wired network will be installed and wired computers will be activated in some of the schools that meet the criteria.
International reports
In May 2011, as part of the Council of Europe’s resolution on non-ionizing radiation and sensitivity to radiation, the Council called on European countries to keep schools free of radiation. It is mainly about banning the use of cell phones, cordless phones and wireless networks and computers.
The Canadian Ministry of Industry (INDUSTRY CANADA), which supports, relies on and promotes the non-shielding standard of ICRNIP, performed a radiation test that roughly symbolizes the situation in a classroom with computers and wireless routers.
The test results showed high radiation levels (but lower than the non-protective ICNIRP standard) at certain points in the classroom at a level of 2.4uW/cm2, and near the routers levels between 105.9 uW/cm2 and 77.3 uW/cm2.
A British body called the Health Protection Agency, acting for the British government, which has a long history of denying the harm of cell phones and non-ionizing radiation and which also favors the non-shielding standard of ICNIRP, carried out a simulation and test of radiation from wireless routers and computers in the classroom. Here, too, the test results showed high radiation levels (but lower than the non-protective ICNIRP standard) near the computers 2.2uW/cm2 and near the routers a level of 8.7uW/cm2.
