Do smart meters cause any other health problems?
Smart meters have not been studied to see if they cause health problems. Studies have looked at RF radiation from other sources. Exposure to large amounts of RF radiation, as from accidents involving radar, has resulted in severe burns. No other serious health problems have been reported.
One concern expressed is that the RF waves produced by smart meters might interfere with electronic medical devices such as a heart pacemaker. A study that examined the effect of smart meters on pacemakers and implantable defibrillators found that the smart meters did not interfere with these devices.
Radiofrequency (RF) Radiation
Radiation is the emission (sending out) of energy from any source. X-rays are one example of radiation, but so is the light that comes from the sun and the heat that constantly comes off our bodies.
When talking about radiation and cancer, many people think of specific kinds of radiation such as x-rays or the radiation made by nuclear reactors. But there are other types of radiation that act differently.
Radiation exists across a spectrum from very low-energy (low-frequency) radiation to very high-energy (high-frequency) radiation. This is sometimes referred to as the electromagnetic spectrum.
The electromagnetic spectrum illustration below shows the possible frequencies of electromagnetic energy. It ranges from extremely low frequencies (such as those from power lines) to extremely high frequencies (x-rays and gamma rays), and it includes both non-ionizing and ionizing radiation.
Examples of high-energy radiation include x-rays and gamma rays. These rays, as well as some higher energy ultraviolet (UV) rays, are forms of ionizing radiation, which means they have enough energy to remove an electron from (ionize) an atom. This can damage the DNA (genes) inside of cells, which can sometimes lead to cancer.
How are people exposed to RF radiation?
People can be exposed to RF radiation from both natural and human-made sources.
Natural sources include:
- Outer space and the sun
- The sky – including lightning strikes
- The earth itself – most radiation from the earth is infrared, but a tiny fraction is RF
Human-made RF radiation sources include:
- Broadcasting radio and television signals
- Transmitting signals from cordless telephones, cell phones and cell phone towers, satellite phones, and 2-way radios
- Wi-Fi, Bluetooth® devices, and smart meters
- Some medical procedures, such as radiofrequency ablation (using heat to destroy tumors)
- “Welding” pieces of polyvinyl chloride (PVC) using certain machines
- Millimeter wave scanners (a type of full body scanner used for security screening)
Some people can have significant RF exposure as part of their jobs. This includes people who maintain antenna towers that broadcast communication signals and people who use or maintain radar equipment. Other people who may have higher levels of RF exposure include some healthcare workers (particularly those working near MRI scanners) and people who work with devices that use RF radiation, such as plastic sealers, certain types of welding equipment, and induction heaters.
Most people are exposed to lower levels of RF radiation every day, from RF signals all around us. They come from radio and TV broadcasts, Wi-Fi and Bluetooth devices, cell phones (and cell phone towers), and other sources.
Some common uses of RF radiation
Microwave ovens work by using very high levels of a certain frequency of RF radiation (in the microwave spectrum) to heat foods. When food absorbs microwaves, it causes the water molecules in the food to vibrate, which produces heat. Microwaves do not use x-rays or gamma rays, and they do not make food radioactive.
Microwave ovens are designed so that the microwaves are contained within the oven itself. The oven only makes microwaves when the door is shut and the oven is on. When microwave ovens are used according to instructions, there is no evidence that they pose a health risk. In the US, federal standards limit the amount of RF radiation that can leak from a microwave oven to a level far below what would harm people. Ovens that are damaged or modified, however, could allow microwaves to leak out, and could pose a hazard to people nearby by possibly causing burns.
Full-body security scanners
In many airports in the United States, the Transportation Security Administration (TSA) uses full body scanners to screen passengers. The scanners currently used by the TSA employ millimeter wave imaging. These scanners send out a small amount of millimeter wave radiation (a type of RF radiation) toward the person in the scanner. The RF radiation passes through clothing and bounces off the person’s skin, as well as any objects under the clothes. Receivers sense the radiation and create an image of the outline of the person.
Millimeter wave scanners do not use x-rays (or any other kind of high-energy radiation), and the amount of RF radiation used is very low. According to the US Food and Drug Administration (FDA), these scanners have no known health effects. However, TSA often allows people to be screened in a different way if they object to screening with these scanners.
Cell phones and cell phone towers
Cell phones and cell phone towers (base stations) use RF radiation to transmit and receive signals. Some concerns have been raised that these signals might increase the risk of cancer, and research in this area continues. For more information, see Cellular Phones and Cell Phone Towers.