|T O P I C R E V I E W
||Posted - 05/29/2021 : 21:49:10
This is concerning my child's room which is on the top floor of the house. Meter in hand I am getting a reading of around 55v/m at standing head level. 75v/m near the ceiling. When the meter is not in hand and propped on a table, it can range from 3-15v/m depending on the location.
I understand the body acts as an antennae for static electricity. In this situation my meter is constantly reading as "Mixed", and I never see the word "Static", but I am assuming its heavy static from how high the numbers are when the meter is in hand vs. when its propped on a table.
I am seeing mixed opinions on how safe/bad "static" EF is for you. I read someone say not to be so concerned with "static" and others to say to use the readings while the meter is in hand because its an accurate reflection of what the body is receiving. If the body is acting as an antennae and the meter is reading 50v/m EF while in hand, the body is still enduring that 50+ v/m regardless, no? Wouldn't that be unsafe still?
So first, am I correct in assuming the bulk of this EF reading is Static even though its reading as "Mixed", and more importantly, how concerned should I be about the readings I am getting? I am assuming there is power running across the ceiling since this is our top floor. Not sure what I could do in this situation.
Thank you so much for any insight!
Edited to add "v/m" to my meter reading numbers.
|3 L A T E S T R E P L I E S (Newest First)
||Posted - 06/01/2021 : 12:28:45
@Damien thank you for the very informative answer, @ellie, the card states that the > 3 is when exposed to AC EF mostly present under high voltage power lines. Inside the house, mostly they are static charge.
||Posted - 05/30/2021 : 07:18:29
I really appreciate your response. The only thing I have to go on on regarding what safe thresholds are is the card that came with the meter. Regarding EF specifically the card says:
<3 v/m - Normal
>3 v/m - Check regularly
> 50v/m - Not recommended for long time stay.
Most of my house is in the "normal" range so my upstairs was definitely surprising to me and considering the thresholds on the card, it has me concerned with that room in particular.
I am trying to follow along on your comments.... I am sure electricity is complicated but I am unsure what might make the reading go from 5v/m to 75v/m if not for static electricity. I am also unsure which reading I should trust more (in-hand or on table) for a reading of what my sons body is actually being exposed to. The card thresholds above make me concerned for either really. I will continue to do more research in hopes to understand it better. Thanks again for your time.
||Posted - 05/30/2021 : 01:15:46
in a room, the electrostatic field cannot be very high except in winter when the weather is very dry and the central heating is on (which further reduces the humidity rate).
If you have carpeted floors you will easily notice this by receiving discharges when you step on it and touch doorknobs or other objects. it is not particularly dangerous but in some countries it is mandatory that the carpet be wired and grounded. but in this case it charge yourself with electrostatic charge and generate an electrostatic field between you and the room.
What is really present inside a room are low frequency fields due to the electric power network (110v or 230v), therefore EM fields at low frequencies of 50Hz or 60Hz.
These are not supposed to be dangerous and we can't do much against it, if your house ground probe is faulty it will increase this field, you could ask an electrician to check it, but you have to be confident, some will tell you which is defective just to change it even if it is compliant, but for other reasons it's always good to have it checked.
It is also important that all devices that need to be grounded are truly grounded (devices that have an ground connection to their outlets)
But don't worry too much with these fields, in any case don't do anything rash or expensive just because you were told that ...
There are extreme cases with people living in apartments just above 40,000v transformers supplying multiple entire apartment residences, I find this unacceptable. otherwise I don't think there is any problem to have.
It is possible that you have electric cables in your ceiling which pass to supply the lighting.
Whether the best measurement is made by holding the detector in your hand or by placing it on a table, it depends on what you want to measure:
if you put the detector on a table, you will measure the ambient field and the device must have been calibrated for that. therefore the measurement must be good.
If you hold it in your hand, what will happen is quite complex to explain, but the measurement will be distorted and your presence will also increase the field because your body is conductive and will shorten the induction distance of the field. but by doing like that, by getting as close as possible to the source of the radiation, you will be able to go to extreme measures which then no longer have any meaning or any value.
I'm not expert but 3-15V/m seem to me very low and very safe
For reference, between two terminals of 9v battery there is 9v and around 1cm distance, this induice a electrostatic field of 9v/0.01m =900v/m between the two terminals