Is there harmful EMR from DC systems?

[Christian W.]

The switchboard on my boat is within a double sided wooden bulkhead space directly behind my head on my sleeping berth. Is there an EMR expert out there who could tell me if that is harmful to health? Thanks!

[MartinR]

Trolling?

[Christian W.]

No, not trolling. DC electro-magnetic radiation is a fact - all I want to know is whether such proximity to the wiring net could be harmful in the same way that AC has been suspected (and negatively) researched regarding harm. To allay your fears of trolling, I'd encourage you to google DC EMR, there's lots there to learn!

[mickt243]

“DC EMR” would be magnetism.

You already live on a massive magnet.

Plenty of people believe that being in the presence of magnetism is good/healing. I think they’re nut jobs.

If being near magnetism was good, we’d live forever.
If being near magnetism was bad we’d all be dead already.

Oh, and I just did a google search on the term “DC EMR”, returned no results valid to this discussion, not even ones from crackpot conspiracy whack jobs.

[Chotu]

Certainly, there would be a lot more from alternating current than DC current. You see, it takes a changing current or a changing electromagnetic field to create any issues. Direct current is not a changing field for the most part, so you are all set.

[GordMay]

No.


In the case of workers wearing a pacemaker or other electronic medical device, the ACGIH recommends limiting exposure to 1 kV/m for electric fields, and 500 µT for magnetic fields.

The strength of an Electric field increases with voltage. Electric fields are measured in kilovolts per meter (kV/m). Typical electric field levels in the home, and at work, are less than 0.1 kV/m (kilovolt per meter). Electric fields within one foot of small appliances are in the range of 0.02 to 0.2 kV/m, while the field immediately adjacent to the heating wires of an electric blanket can approach 10 kV/m. Electric field strength decreases with distance from the source. Most building materials shield electric fields to some extent.


Magnetic fields arise from current flows. DC magnetic field flux density is measured in in microTesla (µT), or milliGauss (mG), or amperes per meter (A/m). Field strength decreases with distance from the source. Magnetic fields are not attenuated by most materials.
The Magnetic field produced by a microwave oven, in use, at a distance of 30 cm (1 ft), is about 4 μT to 8 μT. Strength of Earth's magnetic field varies between 31 μT and 58 μT, depending on latitude.

[MartinR]

No, D/C creates an magnetic field, but as the currents are not changing there is no electro magnetic radiation.

The magnetic field is obviously not harmful to people as noted above. It is very weak.

[Zil]

It is a well known fact, every living being exposed to gravitational fields will die.

[MartinR]

Originally Posted by Zil

It is a well known fact, every living being exposed to gravitational fields will die.

[Baba Buoy]

Long term studies of power company workers, who are exposed to massive amounts of EMF throughout their careers, have found no detectable ill health effects. One would think that this type of evidence would bury peoples EMF fears once and for all, but that would be no fun at all. The multi-billion dollar litigation industry was been biting on the bit for years to file massive class action suits over EMF concerns. They are not going away anytime soon. RoundUp and Baby Powder type of lawsuits will keep these sharks circling for quite a while.

[roland stockham]

Nowhere on a boat has EMR approaching anywhere near the average land based home or city street. The only significant sources being a back-stay arial but only during transmission, the alternator when the engine is running and an operating radar.

[stewie]

K2EMF meter.com is sold for paranormal investigations but as it measures in milligauss it can be used to measure EMR for whatever. Try it near your microwave or the electricity meter in your home. You will be surprised by the reading and the distance.

[crazyoldboatguy]

Originally Posted by Zil

It is a well known fact, every living being exposed to gravitational fields will die.

And Zil wins the Internet for today!!!

[AndyEss]

DC EMR fields close to a vertebrates CNS (central nervous system) may cause inexplicable symptons. Sir Alexander Volta showed this conclusively while dining on frog legs basted in a delicious vinegar based sauce - voila the world's first re-animation of the dead.
The way to counteract the induced fields is by cross-polarization. If you are in the northern hemisphere (and are right handed) one should sleep in a condition such as yours $(strong field at top of spine) with the right arm and left leg joined together. For the southern hemisphere, the position should be reversed. It is critical that bodily electrical continuity be maintained, despite somnambulance, so fastening the limbs with some semi-conductive material similar to skin, say leather, is in order. It may prove helpful if a sleeping partner, or partners, are involved.
Finally, the unheralded Florentine Renaissance natural philosopher, Benito Franklino observed that in lieu of tying limbs together, one might try a metallic, conductive cap to ameliorate such situations.
Buon gusto!

[a64pilot]

A cheapo AM radio ought to detect if there is a significant EM field close by.
One job I had for 20 years had me wearing a helmet that had metal
“cans” as part of the IR system that very accurately measured your exact head position, it was very high voltage, very low amperage.
There was considerable concern from many of us, but don’t think anything was ever linked to it, or course I don’t think it was ever really looked at either.

Commercial pilots and flight crew are exposed to significantly higher levels of radiation in nearly all the bands than us terrestrial folks, and I know there has been significant studies there, and no link was found.
Also people who live in brick houses the background radiation is much higher.

Finally if you live under a high voltage transmission line, the level of radiation is unbelievable. My friends house in Tx. You could stand in his yard holding a fluorescent tube and it would light up as if by magic, from the RF of course, and I don’t think there has been a health link found there either.

In short, low voltage DC, there is likely almost no RF coming off of that, I wouldn’t worry.