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EMF magnetic radiation

Thu Mar 01, 2018 6:03 am

We recently purchased a 2017 Ford Focus Electric and noted that the battery is located very close to the back seat, where our children sit. We are concerned about magnetic radiation exposure. I measured the magnetic field being emitted using a Trifield meter and found it very high (over 100mG) when the car is braking or accelerating.

Has anyone else looked into this?

Any suggestions on how to minimize magnetic radiation exposure?
Last edited by suz135 on Thu Mar 29, 2018 5:27 am, edited 1 time in total.

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Re: EMF magnetic radiation

Sun Mar 11, 2018 3:22 pm

No idea.

Curious, though. If you are concerned about exposure to electromagnetic effects, why did you buy an electric car?
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Re: EMF magnetic radiation

Mon Mar 12, 2018 5:41 am

Seeing as how current flowing creates a magnetic field and an electric car by design and necessity will have some serious current flows, why did you buy an electric car if you are concerned about magnetic fields?

Building a Faraday cage inside your car is about your best bet and even then it probably won't shield to your level of liking nor be very practical. Heavy thick steel is about the only "practical" thing I can think of. I put that in quotes because heavy thick steel would be even less practical than trying to construct a Faraday cage inside your car which itself is already somewhat of a Faraday cage.
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Re: EMF magnetic radiation

Mon Mar 12, 2018 7:18 am

That is pretty cool. Wonder if you can do some neat science experiments back there?

I can't imagine it causing health problems.... unless you have a significant amount of steel inside your torso?
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Re: EMF magnetic radiation

Mon Mar 12, 2018 5:54 pm

These meters are typically measuring AC emf, which in the FFE would be generated by the motor and AC inverter at the front end of the car. In any case, data concerning deleterious health effects of weak emf are equivocal at best. If it turns out that there are small increases in e.g. cancer risks, the main issue would be long-term exposure levels rather than very short term transient exposures to levels that are still fairly weak. IIRC, typical household background emf ranges from ~1-10 milligauss but certain high amperage appliances could temporarily spike that to much higher intensities (particularly those requiring close proximity while using - e.g. hair dryers and vacuum cleaners) - and exposures from these sources will likely be much longer than an occasional few seconds of braking.

I you're that worried about possible emf risks, focus on where the kids are spending the most time. E.g. throw out the electric blankets and move the child's bed away from the wall carrying a 50 amp heat-pump circuit. If the peak emf intensities in the car are really worrying you, then accelerate and brake as slowly as possible - but I don't think this would affect total AUC exposure.

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Re: EMF magnetic radiation

Mon Mar 19, 2018 12:45 pm

Any magnetic field generated by the car won't have any dangerous effect on your children's bodies. MRI machines operate at over 5,000,000 mG with little to no effects (rarely some slight vertigo). You are good to go!
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Re: EMF magnetic radiation

Mon Mar 30, 2020 1:09 pm

[I'm going to copy/paste my reply from a nearly identical thread]
I realize I'm a bit late to the show here, but for the benefit of anyone else who may happen on this thread:
I had thought of the possibility of Electromagnetic Radiation in the front, near the motor (particularly when the magnetic strip on two of my gift cards ceased to function), but I wouldn't have thought of it occurring near the batteries. I certainly wouldn't have expected it to reach so high as 100mG. I've done some research a while back on the association of EMFs and various health issues, and I'd say your concerns are valid. As others have mentioned, singular exposure for a limited time doesn't seem to have any noticeable effects. However, repeated or long-term exposure has been potentially linked to health effects in all humans, with children being particularly susceptible to any sort of energy radiation. Still, if your kids wont be spending much time in the car, I wouldn't worry too much. If you really want to do something about it, I believe copper or steel sheeting (or perhaps a combination of the two) would effectively block/absorb the EMR. You'd just have to do some experimenting with it.
EDIT: So, I recently took my FFE apart to see how the battery is put together and such, and discovered an interesting caveat: the primary cables between the batteries and the motor are shielded, much like a coax cable. The battery itself is entirely encased in a steel box. So, I suspect that perhaps the EMF is coming largely - if not entirely - from one or more small locations, such as where the cables terminate to the connector on the battery case. Thus, if a person wanted to, it may be fairly easy to shield particular locations and completely block any radiation.
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