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EMF Radiation
- Thread starter Ben W
- Start date
No. I do not, nor have I ever worked for Tesla. I do not own stock in Tesla (though I was probably pretty dumb not to buy some). I do own a Roadster and Model S.
Tesla is not perfect and I have been known to criticize them on more than one occasion in this forum. On a couple of occasions I have lobbied them to change their policies (successfully in one case). However I do believe what Tesla are trying to do is very important for the world - not to mention pretty amazing technologically - and I am therefore a big supporter.
As for my recent contribution to this thread: I am offering my opinion, which is informed by my experience as a Professional Engineer who has significant experience with EMF fields, including shielding, interference, etc. It has nothing to do with my opinion for or against Tesla. It has to do with my understanding of the scientific principles involved.
bonnie
I play a nice person on twitter.
Why don't you go test drive a Model S and bring your meter? You obviously experience things differently in certain cars and attribute that to EMF so no matter what people here tell you only you can know if the Model S will work for you.
Raffy.Roma
Rome (Italy)
IMO the electromagnetic field generated by the electric heating system is at very low frequency. You can measure it of course, but because of its very low frequency is not dangerous at all for us.
RichardC
Cdn Sig & Solar Supporter
I have a very simple (Green / Yellow / Red) (OK / Caution / Danger) EMF meter and don't know the EMF levels associated with the different coloured lights. (Not highly scientific, I admit, but it provides some comparative information about EMF levels.)
Jaff
Active Member
I'm looking forward to test driving and hopefully ordering my first Tesla this weekend. I do believe there is some merit to understanding the electric and magnetic fields of EVs in general, and Teslas in particular. My thesis is that the positive outweighs the negative in case if the Model S but my jury is still out and I'm looking for more evidence. Life is about balance, so I'm not looking for perfection simply minimising the effects of pollution (air, water, electro) especially for my kids, without going back to the dark ages.
My thoughts re some of the issues raised on this thread:
- Aluminium casing has a permeability of ca 1, which is roughly the same as air. Iron and steel are better (ca 200) but the best is to use a magnetised mesh (ca 10,000+) with no gaps. It's relatively cheap and easy to source, as they are priced to cover large areas like walls. Would require some design to avoid leeks at the edges, but a bit of design and experimentation in the factory could lead to awesome results with very little investment. This technology is readily available for living areas, hospitals etc
- Pulsating frequencies are the worst, biological tolerance levels are at least an order of magnitude lower for these. The most dangerous frequencies to the human body are 30 MHz és 300 MHz, here is where you need to pay close attention. Tolerances are way better for the 1kHz-100kHz range, everything else is in-between
Limited exposure in an active state (ie commuting to work) is a very acceptable compromise in my opinion. However if you will have kids sleeping in the car on long road trips (as it will be in my case) you'd better look into this topic and compare your findings with traditional vehicles.
So what's acceptable? Of the many industry standards available, probably the most relevant for our purposes is the Swedish monitor standard:
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(continued)
So what's acceptable? Of the many industry standards available, probably the most relevant for our purposes is the Swedish monitor standard:
Frequency Range................MPR II ........TCO '95
Electric Fields:
DC: Static Field...............+/-500 V........+/-500 V
ELF: 5 Hz - 2 KHz...........up to 25 V/m...up to 10 V/m
VLF: 2 KHz - 400 KHz.....up to 2.5 V/m...up to 1 V/m
Magnetic Fields:
ELF: 5 Hz - 2 KHz..........up to 2.5 mG.....up to 2.0 mG
VLF: 2 KHz - 400 KHz.....up to .25 mG.....up to .25 mG
Note: the above measurements are taken at a distance of 30-50 cm (approximately 12-20 inches) at 16 points around the monitor at 3 different levels
Not sure I will have time and get a change for measurements during the test drive - but in case I do the 1000000 dollar question is
which frequency range should I measure in the TESLA?
My thoughts re some of the issues raised on this thread:
- Aluminium casing has a permeability of ca 1, which is roughly the same as air. Iron and steel are better (ca 200) but the best is to use a magnetised mesh (ca 10,000+) with no gaps. It's relatively cheap and easy to source, as they are priced to cover large areas like walls. Would require some design to avoid leeks at the edges, but a bit of design and experimentation in the factory could lead to awesome results with very little investment. This technology is readily available for living areas, hospitals etc
- Pulsating frequencies are the worst, biological tolerance levels are at least an order of magnitude lower for these. The most dangerous frequencies to the human body are 30 MHz és 300 MHz, here is where you need to pay close attention. Tolerances are way better for the 1kHz-100kHz range, everything else is in-between
Limited exposure in an active state (ie commuting to work) is a very acceptable compromise in my opinion. However if you will have kids sleeping in the car on long road trips (as it will be in my case) you'd better look into this topic and compare your findings with traditional vehicles.
So what's acceptable? Of the many industry standards available, probably the most relevant for our purposes is the Swedish monitor standard:
- - - Updated - - -
(continued)
So what's acceptable? Of the many industry standards available, probably the most relevant for our purposes is the Swedish monitor standard:
Frequency Range................MPR II ........TCO '95
Electric Fields:
DC: Static Field...............+/-500 V........+/-500 V
ELF: 5 Hz - 2 KHz...........up to 25 V/m...up to 10 V/m
VLF: 2 KHz - 400 KHz.....up to 2.5 V/m...up to 1 V/m
Magnetic Fields:
ELF: 5 Hz - 2 KHz..........up to 2.5 mG.....up to 2.0 mG
VLF: 2 KHz - 400 KHz.....up to .25 mG.....up to .25 mG
Note: the above measurements are taken at a distance of 30-50 cm (approximately 12-20 inches) at 16 points around the monitor at 3 different levels
Not sure I will have time and get a change for measurements during the test drive - but in case I do the 1000000 dollar question is
which frequency range should I measure in the TESLA?
Johan
Ex got M3 in the divorce, waiting for EU Model Y!
You should measure which ever frequency range that scares you. You seem into this and I'd be interested to know which data you base any fears you're harbouring on. Also, previous measurements done in EVs generally show much lower EMF radiation over a wide range of frequencies as compared to ICEs and hybrids. (Not that it matters much either way, if you ask me).
I have loads of equipment, and each of them need a range setting similar to a multimeter. I'm pretty sure I won't have the opportunity to measure everything during the test drive. It will be an organised test drive with Tesla guys and many potential buyers around. Wouldn't be polite either and I truly believe that the future belongs to EVs so I prefer to avoid misperception, as it's likely that I'm going to buy unless the results are really disappointing. Someone also suggested that the Roadster had higher measurements, so I wouldn't be surprised if the Model S already had a magnetic mesh embedded.
If you are interested, there is loads of evidence on the topic if you look hard enough, but they tend to go against huge vested economic interests (energy companies, media, etc) so as you can expect the voices are muted. Start by googleing Ahlbom & Feychting 1993 or consult WHO publications etc.
Back to the frequency range.. I believe Doug wrote roughly 1kHz for the RPM in one of his earlier posts.
Where should I expect the PWM for 85kWh Tesla motor?
Johan
Ex got M3 in the divorce, waiting for EU Model Y!
Funny you mention Ahlbom and Feychting. When I studied medicine in Gothenburg, Sweden in the early 2000's I remeber that during our semester in Epidemiology and Scientific method we went in to great depth in this and Feychting's other epidemiological studies about cancer and power lines. These are observational studies and very prone to confounding factors and all sorts of bias, from observational to selection bias etc. In short let's agree that if these results could be confirmed in studies with better methodology there would be immense impact on society. But the results are not confirmed, but rather debunked.
As for your conspiracy theories... Well, each to their own I guess.
As for your conspiracy theories... Well, each to their own I guess.
@Luxembourger: I'd encourage you to start by measuring fields in your current car to get an appropriate baseline. Regarding the Tesla measurements, I don't have any expertise to advise you what to measure, but you might be able to tag along in the rear passenger seat with other people getting test drives, provided everyone (including the Tesla rep) agrees.
Have you read the posts up-thread? You are not the first person raising this point, and others have already done measurements, e.g. EMF Radiation - Page 11.
Have you read the posts up-thread? You are not the first person raising this point, and others have already done measurements, e.g. EMF Radiation - Page 11.
@Johan - bit of an empirical pragmatic here so I apologise if I chimed into a sensitive topic- hope I didn't disturb anyone's peace and there is no need to worry. But I still very clearly remember the words of a university professor responsible for environmental science at a leading UK university, when I was on a fundraising tour at the local Rotary Club (I climbed Kilimanjaro in 2006 to call attention to global warming) his response was alone the same lines: observational studies and very prone to confounding factors and all sorts of bias. Not blaming him at all, after all he has to watch his words as a professor at a leading university. Yet I continue to believe that the correlation between temperature increase and industrialisation is not without cause and effect, et voila 10 years later the world is of the same opinion. If everything I read above proves to be true, then the Tesla Model S readings should be comparable or even lower than a traditional car so nothing to be offended about or afraid of.
@Robert - yes I read all 16 pages, and I do hope to get similar results!
@Robert - yes I read all 16 pages, and I do hope to get similar results!
RichardC
Cdn Sig & Solar Supporter
I have performed tests on our Tesla using consumer grade EMF meters on a number of occasions and not found any EMF of any consequence. Interestingly, I was giving a member of the family a demo ride a week ago and they were testing the car with an EMF meter. After not finding any radiation of any consequence around the dash or console or rear seat or floor, he measured the sun roof and all of a sudden started to get measureable EMF. After a minute puzzling over this, I noted that there were power lines strung around 30 feet up wooden poles beside the road. We then confirmed that the power lines, rather than the car, was the source of the EMF. All of which gave me some level of comfort that the EMF shielding in the car seems to have been engineered with some degree of care. (Not a scientific study of all potential frequencies, but somewhat comforting nonetheless.)
I climbed Kilimanjaro 10 years ago to call attention to global warming, as the Kili's iconic ice cap is likely to vanish within our lifetime. During a high profile fundraising event at Rotary Club in London, it turned out that the Club President was a professor and director of the environmental sciences department of the most respected UK university. Following my presentation, he stood up and to my surprise introduced himself as a professor in the field, and gave an explanation to the audience along the same lines: the studies on global warming are observational and very prone to confounding factors and all sorts of selection bias. Not blaming him at all as all he was doing is repeating the party line. This was before Al Gore published "An Inconvenient Truth" which contributed greatly to the acceptance of the causative link between global warning and industrialisation. When I was a kid I remember having the same pitch was applied to correlation between cancer and smoking: correlation maybe but zero proof of causative effect.
Sorry I didn't want to scare you or anyone but I prefer to keep and open eye and a head above the sand and continue to rely on practical empirical data. Not a big fan of calling names on a religious basis. No reason to worry anyhow if what I hear and suspect is correct: the Tesla engine's frequency range seems to be in the least harmful range, and the posted measurements seem to be negligible for the Model S..
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Yes this is exactly what I was planning to do.
Yes I read all 16 pages including the Mythbuster article. What is unclear is which frequency range the measurements were taken in, ie. setting the frequency range to several GHz will show close to zero EMF near a 400V*500A power line, if it is not emitting EMG in that specific range. Try to measure near 50Hz and you'll get different results.
If the engine is pulsating just below 1kHz as explained by Doug. where should I expect the PWM of an 85kWh motor?
RichardC
Cdn Sig & Solar Supporter
It is very rudimentary - Green / Yellow / Red type device which measures from 20 to 10,000 Hz, where:
Green is below 2.5 Milli Gauss
Yellow is 2.5 to 7 Milli Gauss
Red is above 8 Milli Gauss
The car is generally in the Green zone but I have seen Yellow with the heater running around the footwell area. I would note that my vehicle is a Sig and may not be representative of current production.
As noted above, we were getting Yellow readings when driving adjacent to power lines (which seems to suggest that the level of sensitivity is reasonably good).
nwdiver
Well-Known Member
.... for reference an MRI is ~5k - 30k Gauss... or 700k - 4.2M times the levels in a Tesla. If magnetic fields had any biological effects we would see them in an MRI... we don't.
'MRI does not use ionizing radiation (high-energy radiation that can potentially cause damage to DNA, like the x-rays used CT scans).
There are no known harmful side-effects associated with temporary exposure to the strong magnetic field used by MRI scanners.' - FDA
RichardC
Cdn Sig & Solar Supporter
Agreed - That said, I sure wouldn't want to drive across the country in an MRI scanner! :biggrin:
