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Do hybrids have higher level of EMF

I’ve read that hybrid vehicles such as the Prius have a high level of electromagnetic field. Is this true?

Maybe. But EMF isn’t dangerous. If it were, my remains would have been toasted during my last MRI. Or perhaps I’d glow in the dark. Hey, that would be cool!!!

Any electric motor with a high amperage draw will create a significant EMF. I’m reasonably sure that these cars have shielding in place to cut down on the amount that makes it out to other parts of the car, but I have to imagine that the EMF produced in a hybrid vehicle is significant. If you are asking that question in relation to health issues… well, I would challenge you to find any conclusive study that says EMF (especially at the levels produced by a hybrid) poses a significant health risk.

No, my question isn’t about the health consequences of EMF (if any). I’m looking for raw data or measurements of EMF in a regular vehicle vs a hybrid.

While searching the terms “hybrid car EMI” I ran across this website:

Some interesting reading and actual values reported therein. I looked over a number of other sites that came up in the search and found quite a bit of information. If you’re interested, I suggest doing the same.

I looked into this in a posting on (post #23 on this thread):

I found two listings of EMF readings for cars, and the Prius was no different from any other car. The listings are here:

and post #4 in this thread:

The upshot is that the Prius is no different from any other car. You can get much higher EMF exposure from many household appliances and electronics than you do from your car. Even if you are worried about EMFs, your car (including your hybrid) should be low on your list of worries.

I have a Tri Field Meter used to test for EMF fields and just happened to have it on when starting my car one day and noticed the meter jump well above 3mG. Readings surely differ from model to model of automobiles, but long term exposures certainly place them in the caution zone. See article on EMF Fields available at

So, I think you need to read some real science.

According to Consumer Reports…The Prius is no where near the highest.

Looks like no relationship between EMF and whether a car is a hybrid. Having a steel shell between the people and the electronics is a major factor.

As far as I know, hybrids haven’t been banned for people with pacemakers and implanted defibrillators. As long as that is the case, I am pretty sure the driver isn’t exposed to enough EMF to worry about.

The major contributor to EMF in a conventional car is the starting motor and the alternator. Since the starter is only used briefly it isn’t a factor and the alternator isn’t a strong producer of EMF. In a hybrid the electric motors are big and the electromagnets are big therefore these motors will produce more EMF than a starting motor and they run all the time.

So, a hybrid will produce significantly more EMF than a conventional car. Whether or not this is a health issue I don’t know.

There are two important considerations concerning EMF, strength and frequency. I’m going to start with frequency. This can range from 0 Hz (direct current) to microwave and millimeter wave (3-300 GHz) and lightwave (IR, visible and UV) frequencies. Some frequencies can be damaging.

60 Hz can be quite damaging to humans because that is the frequency of signals passed by our nervous system. A 60 Hz shock will confuse the signals to the heart causing the heart to go into ventricular fibrillation. This is where the heart beats out of sync so that blood does not get pumped. BTW, those paddles you see on the doctor shows on TV do not start the heart. They actually use a high powered pulse to stop the heart momentarily so that the signals from the brain can get it back into sync.

Other high frequencies, particularly microwave cause water to heat up, thereby causing cell destruction. The amount of damage or risk of damage by these frequencies depends on the strength of the field. If the field strength is low enough, then no damage occurs, in theory anyway. This is part of the arguments, exactly what is the danger threshold.

There is also a lot of discussion about what frequencies are dangerous. This is a big unknown right now and there is some research going on to find EMF frequencies that might be dangerous, but so far no proof has emerged, i.e. the radio frequencies used in cell phones.

We live in a giant EMF, its called earth. The earth has a large magnetic field, but it is safe to use because it varies very little, It is pretty close to constant. There are multiple EMF’s in the Prius however. Much of it is DC, but the motor generator is a three phase AC unit whose frequency is dependent on engine speed and vehicle speed. Because the three wires feeding this between the motor generator, inverters and rectifiers are very close together and evenly spaced, the cancel each other so that very little EMF escapes the cable structure. Shielding is not necessary and actually could be counter productive if used in this case.

Since there is little DC cabling in this vehicle, I am not surprised that the EMF is not as strong as it is in other vehicles, but it still uses DC for the ignition and accessories in the vehicle.

The fact that numerous studies have failed to find a clear risk from EMF does say something. The fact that individual radio wave photons lack the energy necessary to disrupt cell structures (such as DNA) also weighs against significant health issues. This is in contrast to UV light and other more-energetic photons, which have the energy to cause cell damage and DNA mutations.

Of course, if the microwave dose is high enough to cause heating/boiling, all bets are off.

All this makes me wonder: why do folks choose to worry about EMF, while ignoring the cancer factories that are tanning salons? We know for a fact that UV causes cancer, we’ve seen a rapid rise in skin cancer, but we worry about cell phones and hybrids…

Gosh, I’ve been living under a rock. I thought EMF was Electro-Motive Force (voltage).

Back to the real question. There are numerous areas of concern for electric fields and none of them have proven to be true yet. One reason to be skeptical of electric field danger in a hybrid car is that the electric field generated around the conductors is beneath your feet. Field strength drops as the square of the distance, and your organs and head are a long way from your feet, even in a car. At this point I’m about as concerned as I am about electric fields from power lines - not much.

I agree. Nothing conclusive has been proven regarding electromagnetic fields.

Until then just wrap yourself in tin foil and be done with it.
Yer gonna die of something. Don’t worry about it.

I think it’s likely that hybrids produce a higher EM field–it’s just logical. You have a high-amp inverter plus a large electric motor. Maybe the peak isn’t any higher than ‘normal’ cars, but I’d suspect they emit higher levels than standard cars when cruising on the electric motor, so they emit cumulatively more EM radiation even if the peak is about the same.