How to hide from the electromagnetic spectrum/electrical pol

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Discussion Overview

The discussion revolves around the feasibility of creating a box or cage that provides complete protection from the electromagnetic spectrum and electrical pollution, particularly focusing on extremely low frequency radiowaves and noise. Participants explore materials and designs that could achieve such shielding, including references to Faraday cages and other shielding techniques.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • Some participants propose the use of a Faraday cage for electromagnetic shielding, but note that it does not protect against acoustic noise.
  • Others argue that soundproofing materials are necessary in addition to electromagnetic shielding for complete protection.
  • It is suggested that while 100% shielding from all EM radiation is not possible, significant attenuation can be achieved with thick metal containers.
  • Several participants mention that the effectiveness of shielding depends on the materials used, such as thick copper or galvanized steel, and the quality of construction, including welded seams and absence of gaps.
  • Concerns are raised about the challenges of shielding doors and the potential for small gaps to allow radiation to penetrate.
  • Some participants emphasize the importance of specifying the level of shielding required based on the intended application, as this affects feasibility and cost.
  • One participant notes that static and slowly varying magnetic fields are particularly difficult to shield against.
  • There is mention of the costs associated with high-performance shielding solutions, with references to expensive screened rooms and specialized equipment.

Areas of Agreement / Disagreement

Participants generally agree that complete shielding from all electromagnetic radiation is not achievable, but there is no consensus on the specific materials, designs, or levels of shielding required for different applications. Multiple competing views on effective shielding methods and materials remain present.

Contextual Notes

Participants highlight the need for clarity on the specific shielding requirements and intended applications, as this influences the choice of materials and construction methods. The discussion also reflects varying levels of understanding regarding the complexities of electromagnetic shielding.

sbratva
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Hello.
I need help!
is it possible to create a box/cage (ive seen the faraday cage etc) to give one 100% protection from all/some the electromagnetic spectrums - and from electrical pollution?
"Nothing enters and nothing leaves" style, so it but cut out all that comes outside of it, and blocks anything from inside of it to go out.
The important part is that it gives 100% protection from extremely low frequency radiowaves/and noise.

What materials would you use to such a box?
 
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You already mentioned a Faraday cage. That is it.
 
it does not protect from extremely low freq noise/sound, just to say ;)
 
It does protect from low freq EM waves, as you said "radio waves and noise". If you meant acoustic noise then you should have said so.

Soundproofing materials are also well known. You would need a Faraday shield for EM and soundproofing for acoustic shielding.
 
It's not possible to block 100% of all EM radiation from entering or leaving, but you can get as arbitrarily close as you like, it just gets progressively more difficult the more you want to block out. A sealed box made out of thick metal would probably be the ideal container. What are you trying to shield? Do you need to be able to enter/exit the container regularly? Doors are very difficult to shield, as even a small crack or gap between the door and the door frame, or even dirt buildup between them, will let a great deal of EM radiation in.
 
Drakkith said:
It's not possible to block 100% of all EM radiation from entering or leaving, but you can get as arbitrarily close as you like, it just gets progressively more difficult the more you want to block out. A sealed box made out of thick metal would probably be the ideal container. What are you trying to shield? Do you need to be able to enter/exit the container regularly? Doors are very difficult to shield, as even a small crack or gap between the door and the door frame, or even dirt buildup between them, will let a great deal of EM radiation in.

It all depends how much money you want to spend. A thick copper box with welded seams and absolutely no holes or gaps will do a pretty good job (>100dB suppression) But in the limit, if you want to get measurement data in or out of your box (and Power supplies) then that gives the EM waves a way in and out. Even an optical link requires a 'hole' somewhere. People spend tens of thousands of pounds on good screened rooms.
 
sophiecentaur said:
It all depends how much money you want to spend. A thick copper box with welded seams and absolutely no holes or gaps will do a pretty good job (>100dB suppression) But in the limit, if you want to get measurement data in or out of your box (and Power supplies) then that gives the EM waves a way in and out. Even an optical link requires a 'hole' somewhere. People spend tens of thousands of pounds on good screened rooms.

You should see the EMP shielded building my reserve unit works in... ;)
 
It is hard to shield static and slowly varying magnetic fields
 
If you want top performance get ready to spend real money but a tightly sealed metal trashcan can easily give 80 of effective shielding at most RF frequencies.

Equipment container:
tipsgraph.jpg


Shielded room:
il_series81_chart.gif


Most of the shielding is from steel/galvanized steel laminate with copper mainly for grounds and beryllium or phosphor bronze contact fingers for doors.
 
Last edited:
  • #10
Drakkith said:
It's not possible to block 100% of all EM radiation from entering or leaving, but you can get as arbitrarily close as you like, it just gets progressively more difficult the more you want to block out. A sealed box made out of thick metal would probably be the ideal container. What are you trying to shield? Do you need to be able to enter/exit the container regularly? Doors are very difficult to shield, as even a small crack or gap between the door and the door frame, or even dirt buildup between them, will let a great deal of EM radiation in.

And by ''thick metal'' how thick and what metal? No i don't need to enter or exit, does this also give protection from microwave/or extremely low level of noise
 
  • #11
sbratva said:
And by ''thick metal'' how thick and what metal? No i don't need to enter or exit, does this also give protection from microwave/or extremely low level of noise
The only way you can avoid some 'thing' entering or exiting is to have a battery operated device which records all its results in there. Any wires going in or out (or even holes for optical fibres) are potentially weak points in the screening.
Before you go any further with this, you need to specify what level of screening you actually need. Only then can you decide if it's feasible or affordable or even a trivial problem. This is an Engineering problem and the numbers count.
You might find the information in this link of interest.
 
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  • #12
sbratva said:
And by ''thick metal'' how thick and what metal? No i don't need to enter or exit, does this also give protection from microwave/or extremely low level of noise

I can't tell you how thick since I don't know what you're actually trying to do. You can't block 100% of all electromagnetic interference, so you need to decide how much you want to block. Since I expect that you don't know how much you need to block, it would greatly help if you gave us the details on what you are trying to do.
 

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