Sadly, it appears there’s some false information being presented as the truth when in fact it’s nonsense! As both an engineer and an air purifier owner and reviewer I wanted to bust the myths once and for all.
Do air purifiers give off radiation? You’ll find out the truth here based on the scientific facts, not rumors or superstition.
Read on to learn more. There’s a lot to see!
- Infographic – Air purifier & EMF facts
- Fast facts: Do air purifiers emit harmful radiation?
- The misinformation being spread – What does it mean?
- What is EMF radiation? Where does it come from?
- How air purifiers work (and where the EMF comes from)
- The scientific truth about it all
- What EMF radiation types have been proven to be harmful?
- In summary: the main facts to know
Infographic – Air purifier & EMF facts
Fast facts: Do air purifiers emit harmful radiation?
When someone claims something that millions of people own is supposedly harmful, shouldn’t they be able to back it up with scientific facts?
In this article I’ll explain:
- What the hype is all about
- What EMF radiation is and where it comes from
- Scientific facts and why it’s much ado about nothing
- More things to know that matter
The misinformation being spread – What does it mean?
An example from a website providing misleading information about air purifiers. The main concern I’ve heard from readers is that they’re reading that they produce harmful radiation – causing them to become worried when in fact there’s no need to be.
Some time ago I first heard from a reader and more recently I’ve gotten more comments and questions about this topic. In product reviews and in other places, they’re reading statements claiming (or implying) that air purifiers are potentially harmful to your health due to “radiation.
You shouldn’t base your decisions on random strangers on the internet who aren’t qualified to make these (incorrect) claims – but instead on facts and what science actually says!
There’s a huge difference between a person at home taking measurements vs a proper study done under controlled conditions and correct test procedures. After all, isn’t that what scientists and labs are for?
That’s why I wrote this article – so you won’t be misled into believing false claims and won’t avoid buying air purifiers based on that.
What is this “radiation” that people are talking about?
When the word “radiation” is used here when we’re talking about air purifiers. We’re not referring to nuclear radiation.
The word “radiation” normally refers to materials that give off radioactive particles like uranium and other radioactive materials that can result in extreme environmental and health problems in both humans and animals.
Instead, we’re referring to electromagnetic fields that are radiated (EMF).
What is EMF radiation? Where does it come from?
Magnetic and electrostatic fields are created when electrons flow through an electrical conductor. The strength of the fields depends on the amount of electrical current and other factors. Motors like those to drive a ceiling fan, motors in your car, and inside an air purifier use magnetic fields to create motion that allows the fan to move air.
I’ll spare you the very complicated (and boring) physics of it all. Believe me when I say my electromagnetics class was one of the single most difficult engineering classes I had in college!
Don’t worry, though – the basic idea isn’t that hard to understand.
Just saying “radiation” actually isn’t the right description – it can give people the wrong idea and lead to confusion or misunderstanding.
After all, we’re talking about electricity and air purifiers, not nuclear materials for heaven’s sake!
How electromagnetic fields (EMF) are produced and what they do
When the electrical current (electrons, as you might recall from science class) flows through a conductor like a wire, 2 types of fields are produced:
- Electrostatic fields
- Electromagnetic fields
Electrostatic fields are a type that acts as a voltage potential in the air because of an electrical charge, much as static electricity does. In a similar way, electromagnetic fields are created too, and radiate, or move outward, a lot like how a magnet produces its magnetic fields.
As we all know magnetic fields attract objects. They also can create the movement of electrons (called induction) in nearby metals.
When we talk about radiation, we’re simply talking about the fields that ALL electrical and electronic devices – not just air purifiers – produce.
The strength of these fields is commonly measured in units called Gauss or Tesla, named after the early scientists who pioneered the understanding we have of them today.
Magnetic fields are critical for the things we use
Electric motors like those that turn a fan to blow air for cooling your room or cleaning the air need magnetic fields to create motion. To do that, electric motors use a huge length of wire windings.
When a long length of wire is wound into a coil or winding like in a motor, the magnetic fields “build up” and are much stronger. That, and the electrical current flowing in them, create the fields.
The thing is that unless they’re very strong they can’t affect objects or humans or animals nearby. It takes an enormous amount of power to create EMF that is any concern – way beyond anything you’ll get from your electronics, appliances, and an air purifier or fan.
Magnetic and electrostatic field strength drops significantly with distance. Even a few feet or meter away the fields reaching you (as who stands right in front of electronics?) are much weaker than right next to the source.
Another very important thing to know is that these fields are much weaker further away from them – meaning you’re almost never exposed to their full strength, which again is typically very small (a few thousandths of a Gauss (milliGauss).
That’s why radio and television stations, for example, use thousands and even hundreds of thousands of watts of power. It takes an enormous amount of power to get a good high-frequency radio or TV signal to an antenna in your home over a long distance.
The appliances and machines in your home and workplace generate only a fairly small amount in most cases.
How air purifiers work (and where the EMF comes from)
Shown: The main components of a Levoit LV-H132 purifier. Air purifiers use a power source and control an electric fan motor in order to move dirty air through the filters to clean it. Most use alternating current (AC) from a wall outlet in your home and “chop it up” with control electronics. This allows running the fan at different speeds and more efficiently, too. (Note the yellow section in which the motor’s wire windings are)
Ever heard of a direct current (DC) motor? You might remember them from battery powered toys or some of the science experiment kits you played with as a kid. While they’re good for some things, alternating current (AC), which is what is supplied to your home from the power company is used instead.
But why? There are several good reasons AC motors are used in nearly all appliances and electric fans, but mainly it’s because of their increased power output and efficiency.
How an air purifier fan motor works
Air purifiers use an electric motor, powered by alternating current (AC) in most cases, to turn a fan and move & clean air. An electronic board regulates how much power is applied to the fan to allow different fan speeds. Both the motor and the operation generate EMF fields around it (as do other devices too).
Most air purifiers use standard AC power connected to an electronic motor control board and the fan speed switch (or button). The low-frequency AC is “chopped up” and modified by a pulse width modulation (PWM) electronics circuit board to control how voltage is applied to the motor.
This is how we’re able to get different tightly regulated fan speeds without wasting power as was done with products back in the old days.
The PWM motor control board isn’t a high-frequency controller like you’d find with radio or cell phone signals. Instead, it’s a lower-frequency design that works several thousand times per second typically. This frequency range is called “kiloHertz” (kHz).
Since the fan motor uses a lot of tightly wound wire as coils and also the fast pulsing of the power supply, EMF is generated anytime the purifier is turned on. Note that the amount of EMF changes based on the amount of power being drawn (electrical current required).
However, most air purifiers draw only about 12-55W watts based on my measurements & the fan speed chosen, so they create a small amount of EMF.
Many appliances and machines draw a lot more power and generate more EMF.
The scientific truth about it all
What people who make claims about air purifiers (or any other small, typical source of EMF) aren’t telling is that for decades no scientific test has proven any proven harm from exposure to low levels of low-frequency EMF like air purifiers produce.
A 2002 study from the World Health Organizations’s International Agency for Research On Cancer found that there was no evidence of physical harm or cancer in humans or animals under study.
In fact, even much larger amounts like from current-hungry industrial machines haven’t been proven to cause any harm to humans, either.
The simple facts are the following:
- Scientists disagree regarding the conclusion that EMF can cause cancer, for example.
- There are no studies that have ever found definitive proof of harm (aside from an exception, see below).
- You’re likely to be harmed by high levels (high frequency, higher power), if at all possible, and certainly not weak devices like an air purifier.
- The EMF from an air purifier or other electrical devices drops drastically the further away you go – so your exposure is even smaller.
It’s important to be realistic – you can’t avoid EMF totally.
There’s an important point I need to make here before we continue: the EMF given off by air purifiers is no different (and even less than) sources you’ve been around already for years.
Here are some examples:
- The blower fan in your car or truck (the dashboard fan that blows air through the vents)
- Ceiling fans and other cooling fans
- Certain types of light fixtures and heaters
- Many appliances
- Machinery in your workplace (industrial machines, in particular, can be a big source of high EMF levels)
- Radio and cell phone high-frequency waves
The truth is that you’re surrounded by EMF everywhere. However, exposure to certain kinds of EMF may be potentially harmful, as you’ll see below.
What EMF radiation types have been proven to be harmful?
There has, in fact, been demonstrated evidence by the National Toxicology Program in the testing of abnormalities in lab rats caused by heavy cell 2G & 3G phone exposure. An increase in DNA damage along with the growth of malignant tumors was discovered in the mice & rats under test.
Additionally, the IARC has also concluded that radiofrequency & microwave EMF fields may possibly be carcinogenic.
Unlike air purifiers and other standard appliances or products around, this doesn’t refer to low-frequency fields but high frequency. Examples of that are signals in the millions of cycles per second (Megahertz [MHz]) and billions of cycles per second (gigahertz [GHz]).
This includes various devices like radio broadcasters, radio & communications towers, and wireless cell phone use.
In summary: the main facts to know
In summary, there’s no truth to the hype about air purifiers generating “unhealthy levels of EMF.” It simply isn’t true, there’s no proof to the claim, and it also ignores several important facts (while providing no proof).
In other words, it’s nonsense.
Here are the main facts to take away after reading:
- There’s no scientific basis to the claim that air purifiers produce potentially harmful EMF. In fact, scientific studies have proven otherwise (see cited paper above).
- Air purifiers (and many other devices) do produce some EMF, however, these are (1) generally small levels that (2) dramatically decrease in strength the further away you are.
- You’re surrounded by EMF from many sources, and from the same type of EMF that air purifiers create: in your home, your car, and in the workplace. It’s nothing new.
- Air purifiers produce low-frequency EMF, not the high-frequency/high-power type that has been suspected to create cancer in scientific tests (RF, wireless phones, and other types with high exposure).
- If you see a recommendation that you “should” by a DC motor air purifier, you’re being misled. Not only is it not necessary, but very few high-quality purifiers use a DC motor. The best models use an AC design.
Hopefully this helps clear up the confusion and will help avoid being influenced negatively. Air purifiers are a great way to improve your quality of life, your comfort, and even stay healthy.
HEPA filter purifiers are used by millions of happy owners every day and are a safe and effective way to clean your air.