The number of wireless devices in daily use continues to grow; there are mobile devices, PCs, cars, home electronics and the list keeps expanding. Electromagnetic waves by definition also produce electromagnetic radiation that have potential health issues. There have been concerns about the impact of electromagnetic radiation for at least 40 years. The concerns increased with the growth of cell phone usage in the 1990s.
Electromagnetic waves by definition also produce electromagnetic radiation that with it brings potential health issues. Long-standing concerns over the last decade have only increased with the near ubiquity of cell phone usage that began in the 1990s.
The good news is health-related regulations on the use of electromagnetic radiation for many frequencies that are used in consumer applications. International regulations include World Health Organization guidelines, the International Commission on Non-Ionizing Radiation Protection and the International Agency for Research on Cancer.
In the U.S., regulators include the Federal Communication Commission, National Council on Radiation Protection and Measurements, the IEEE, Centers for Disease Control and Prevention along with the Food and Drug Administration.
Why am I writing a column on electromagnetic radiation, perhaps stirring the pot on a sensitive issue for many industry segments?
The reason is that we now have many more devices emitting electromagnetic radiation, a total expected to grow to hundreds of millions in the U.S alone. These devices are regulated by different agencies that may not talk to one another. More importantly, they are probably not looking at the big picture that includes the health impact of electromagnetic radiation accumulation from all devices over time.
The goal of this column is to ask some question, give some estimates on device growth and hopefully provide a few useful perspectives. In other words, this column will have more questions than answers and others need to explore these questions to get ahead of the curve to make sure that electromagnetic radiation does not become a future problem 10 or 20 years from now.
I have used a variety of sources and they will provide you with additional information:
Electromagnetic radiation research and regulation
WHO established the International EMF Project in 1996 to assess the scientific evidence of possible health effects of electromagnetic radiation in the frequency range from 0 to 300 GHz. In 1998 the International Commission on Non-Ionizing Radiation Protection (ICNIRP) published the electromagnetic radiation guideline limits for the full frequency range from 0â300 GHz.
WHO and other organizations have conducted extensive research into possible health effects of exposure to many parts of the frequency spectrum. All reviews conducted so far have indicated that, when exposures are below the limits recommended by the ICNIRP guidelines, such exposures do not produce any known adverse health effect. The ICNIRP guidelines have been adopted by over 80 countries and is the most respected limit.
In March 2020, ICNIRP updated its guidelines for exposures to frequencies over 6 GHz, including the frequencies used for 5G. ICNIRP added a restriction on acceptable levels of exposure to the whole body, added a restriction on acceptable levels for brief exposures to small regions of the body, and reduced the maximum amount of exposure permitted over a small region of the body.
In 2011, International Agency for Research on Cancer (IARC), an agency of the World Health Organization, classified wireless radiation as Group 2B â possibly carcinogenic. Group 2B designation means that there âcould be some riskâ of carcinogenicity, so additional research into the long-term, heavy use of wireless devices needs to be conducted. To date, no adverse health effects have been established as being caused by mobile phone use.
Electromagnetic radiation device growth
The number of devices with electromagnetic radiation has grown dramatically in the last 25 years due to the explosion of mobile phones and personal computer networks. The connected car and autonomous vehicle technology are the next growth curve that will add many more devices with electromagnetic radiation.
The next table summarizes the current status and future growth estimates of these devices and their electromagnetic radiation expansion. The table includes four data categories. The electromagnetic radiation source is the type of wireless signal that is usedânote that several devices have more than one electromagnetic radiation source. The place of exposure is where the radiation happens in general terms.
The daily exposure is a range estimate of how long the exposure may last. A current estimate and a 2035 forecast are included. The daily exposure time is not how much usage time, but the time the device is on and is providing electromagnetic radiation.
The last column is an estimate of how many devices with electromagnetic radiation are in use currently with an estimate for 2035. The devices in-use per capita estimates are meant to give perspectives on market size and are expressed as a percent per capita instead of millions in-use. I think this gives a better perspective and the percentages can be used to estimate multiple countries.
The U.S. had 335 million people in July 2021. Since around 18% of the U.S. population are under 15 years, few devices per capita will surpass 85%. By 2035, the U.S. will have around 365 million people.
There are three main device categories with electromagnetic radiation: smartphones, Wi-Fi networks with their connected devices, and devices in automobiles. Autos have three segments: connected vehicles, ADAS and eventually AVs will join the list.
The mobile phone became the first high-volume wireless device with electromagnetic radiation issues in the 1990s. Most users held the device close to the ear and hence the brain could be exposed to radiation. Regulations were adopted in response to the rapid adoption of mobile phones at the time. Today the vast majority of wireless phone customers have, to a large degree, switched to a hands-free usage pattern with wired or wireless earphones.
Today most smartphones usually have three electromagnetic radiation sources: cellular modem, Wi-Fi and Bluetooth. Some smartphones are also using a fourth electromagnetic radiation sources â infrared scanning for face recognition to log into the smartphone.
Smartphones are also the most popular electromagnetic radiation device with usage rates in the 80% of population and is likely to reach the 90% range in 2035.
The smartphone per capita is estimated at 90% in 2035 which is equivalent to up to 330 million smartphones providing electromagnetic radiation around the clock as many people leave their device on all the time.
When the smartphoneâs four electromagnetic radiation devices are added up, the current devices per capita is 250% or 2.5 device per person in the U.S. By 2035 the estimate increases to 320% or 3.2 devices per person.
Wi-Fi networks are the second-leading source of electromagnetic radiation and they are continuing to expand with the number of connected devices growing. Wi-Fi routers are located in homes, offices, hotel rooms, stores and many other places where smartphones and other fixed and mobile Wi-Fi devices tread.
Multiple devices connect to Wi-Fi networks, with PCs being the first and most important devices. There are more PCs in use than there are people in the U.S., with some only having an Ethernet connection to a Wi-Fi router. PCs remain heavily used and provide considerable electromagnetic radiation. The user is quite close to the PC.
The Apple iPad created another PC category that primarily depends on Wi-Fi connections. A small portion will also have a cellular modem. These are used for many hours per day and the user is close to the device.
TVs are also getting Wi-Fi connections due to the growing popularity of streaming programs and movies via the internet. The number of usage hours and devices per capita will grow strongly in the next decade.
There are other devices that connect to Wi-Fi networks such as printers, thermostats, door-locks, light switches and many more. Many of these remain online and have some electromagnetic radiation even if it is at a low level.
The Wi-Fi network devices as a group currently sum up to 220% or 2.2 devices per person in the U.S. By 2035 the estimate reaches 360% or 3.6 devices electromagnetic radiation per person in the U.S.
Cars are adding devices with electromagnetic radiation sources very rapidly. Each of the categories (connected cars, ADAS cars and AVs) is at a different stage of growth.
Connected cars have high penetration in terms of yearly sales but need another decade to catch up until connected cars in-use are close to total cars in-use. Cellular modem is the main electromagnetic radiation device in cars. The connection between infotainment systems and smartphones has greatly increased Wi-Fi connectivity in cars. Bluetooth are also common to connect with smartphones.
The average usage rates of electromagnetic radiation devices are just a few hours since most people only use their vehicles a few hours per day. The usage rates are likely to increase as estimated in the table.
The devices per capita for three electromagnetic radiation devices adds up to an estimated 65% currently and will grow to 210% in 2035, or 2.1 devices per person in the U.S.
ADAS radar use is at the begin of its growth curve and should expand rapidly in the next decade. The number of radars per ADAS car are growing. It is likely that lidar will also be used for ADAS functionality to provide better safety across weather and lighting variations.
Average usage rates for ADAS are a few hours per day and corresponding to driving usage rates. The devices per capita for ADAS radar and lidar are small today and is in only in the 5% range. The growth rate by 2035 is very high and is estimated 60% with 45% from radar.
AVs are in the testing stage and volume deployment is still a few years in the future with some use-case having earlier take-off than others. A recent column has perspectives on AV complexity and deployment perspectives.
AV deployment will grow the number of radars quickly due to the large number of radars used per AV for some AV use-cases. Robotaxis will have the most radars at up to 20 radars per vehicle â from short range to long range lidars. I have used a span of 5-12 per AV in the above table. The radar forecast estimate is conservative due to large AV uncertainties, but the devices per capita are still significant due to the large number of radars per AV.
AVs will also have large numbers of lidars with robotaxis having up to 16 lidars. I used 2-8 lidars per AV in the previous table. Lidar has another potential electromagnetic radiation issue: eye safety.
Lidars are operating at two frequencies that translate into two wavelengths (in nanometers): 905nm and 1550nm. The 905nm is in the visible light that can have an impact on eye safety. There are strict rules on the signal strength of 905nm lidar usage. Over the next five years or so, it is likely that the 1550nm lidar will become the leading technology due to better eye safety. The 1550nm lidar technology has a price premium currently, which is expected to be decline over the next five years.
The lidar forecast estimate is conservative due to large AV deployment uncertainties. Different AV use-cases have varying numbers of lidars per AV. The devices per capita still add up due to multiple lidars per AV for most use-cases.
Adding up the AV radars and lidars per capita remains low for 2035 at only 40%. Â However, if AV deployment is faster than the above estimate, this number could be much higher by 2035.
After doing this column, I was surprised how large the number of electromagnetic radiation devices per capita are currently and the substantial increase for 2035. The next table is a summary of the three device categories that were used. Note that I did not include all devices that have electromagnetic radiation. Cellular base stations are not included and there undoubtedly other categories that are excluded.
These estimates show that the number of electromagnetic radiation devices per capita are currently at 540% or 5.4 devices per person in the U.S. By 2035 the number of electromagnetic radiation devices per person in nearly 10.
Hopefully this column provides useful information that will inspire others to look into this issue and provide more information. I can see a couple of next steps that may be useful:
- We need more information on this subject and more detailed information is needed. I did not break down the devices in terms of the frequencies that are being used. Much more data and analysis are needed on many related topics.
- This subject should be a source of thesis topics for Mastersâ and Ph.D. students. They could do simulation models of electromagnetic radiation by device types, frequencies, use times, number of nearby devices and many other parameters.
- There should be an app for that! It would be useful to have an app that include a database of the electromagnetic radiation characteristics of devices that people are working with. The app user fills out what devices are used, how much time per day/week and other information that let the app calculate how much electromagnetic radiation the user is exposed to over a specified time. This would be very useful for people that are extra sensitive to electromagnetic radiation.
- The next level of this information is a chip-based product that actually measures radiation from our many devices. If we can do it for nuclear radiation, maybe we can do it for electromagnetic radiation. And hopefully the price is reasonable
- I am sure there are many electromagnetic radiation mitigation ideas that will lower the exposure. Turning off some of the devices is simple. Bluetooth and Wi-Fi can be turned off when not needed, which also lowers power usage. Car window coverings that block radar and/or lidar signals in cars would be useful â especially for rear windows, which might end up subjected to strong long-range radar from following cars for extended periods.