# Shielding & remediation

> Shielding material classes and remediation measures with datasheet attenuation, grounding requirements, and documented failure modes.

- Canonical URL: https://emfbase.com/shielding
- JSON: https://emfbase.com/api/shielding
- CSV export: https://emfbase.com/export/shielding.csv
- Records: 10

## Records

- [Aluminium foil and foil-faced board](https://emfbase.com/shielding/foil): A continuous metal layer is a near-perfect RF barrier in principle — 40 dB and better — but seams, staples and penetrations mean installed performance is governed entirely by workmanship.
- [Carbon or nickel shielding paint](https://emfbase.com/shielding/paint): A conductive coating applied to walls and ceilings, quoted at 30–40 dB in the cellular bands; it must be bonded to a grounded conductive strip to also control low-frequency electric fields.
- [Demand switch (Netzfreischalter)](https://emfbase.com/shielding/demand-switch): A relay in the consumer unit that de-energises a circuit when no load is drawing current and re-energises it when a switch is thrown, eliminating the bedroom AC electric field overnight.
- [High-permeability alloy (mu-metal) magnetic shielding](https://emfbase.com/shielding/high-permeability-alloy): The only material class that meaningfully attenuates power-frequency magnetic fields, and even then typically by a factor of two to five in a retrofit — which is why distance and source correction are preferred.
- [Metal mesh and expanded-metal screen](https://emfbase.com/shielding/mesh): Woven or expanded metal used in wall build-ups, vents and window screens; attenuation depends on aperture size relative to wavelength, so a mesh that works at 900 MHz can leak badly at 5 GHz.
- [Metallised shielding fabric (silver or copper on polyester)](https://emfbase.com/shielding/fabric): Curtains, bed canopies and clothing woven with silver or copper, typically quoted at 30–50 dB across the cellular and Wi-Fi bands — enough to remove 99.9% of incident power density when installed without gaps.
- [Plug-in line filter (dirty-electricity filter)](https://emfbase.com/shielding/line-filter) *(provisional)*: A capacitive filter that shunts high-frequency harmonics on a circuit; effects are circuit-specific, can shift harmonics rather than remove them, and can raise magnetic fields near the filter itself.
- [RF-attenuating window film](https://emfbase.com/shielding/window-film): A metallised film bonded to glazing, typically quoted at 20–35 dB, and usually the highest-value single intervention because glass is the dominant entry path for outdoor RF.
- [Shielded mains cable and shielded conduit](https://emfbase.com/shielding/shielded-cable): Screened NYM-style cable or metal conduit with a grounded screen removes the AC electric field at source, and is the correct fix during construction or rewiring.
- [Wired conversion (Ethernet, corded peripherals)](https://emfbase.com/shielding/wired-conversion): Replacing radios with cable is the only measure that removes an RF source instead of attenuating it, and it is usually cheaper than shielding the room the source sits in.