# Metallised shielding fabric (silver or copper on polyester)

> 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.

- Canonical URL: https://emfbase.com/shielding/fabric
- Collection: Shielding & remediation
- Record id: `shielding:shielding-fabric`
- Status: verified
- Last verified: 2026-08-12
- JSON: https://emfbase.com/api/shielding/fabric
- Also known as: EMF fabric, shielding curtain, bed canopy, faraday fabric

## Key values

- **Form:** fabric
- **Targets:** radiofrequency
- **Grounding required:** No
- **Datasheet attenuation:** 30–50 dB — roughly 900 MHz – 6 GHz, datasheet values for flat samples [sbm-2024]

## Failure modes

- Any unclosed gap dominates the result: a canopy left open at one edge can measure barely better than no canopy
- Silver coatings degrade with washing, abrasion and perspiration; conductivity loss is invisible
- Reflective by design — a partially enclosed space can raise levels inside it if a transmitter is inside the enclosure
- Grounding a canopy does nothing for RF and can create a low-frequency electric-field problem if done incorrectly

## Related records

- [Shielding attenuation](https://emfbase.com/quantities/shielding-attenuation): Decibels of field reduction provided by a material. Every 10 dB is a factor of 10 in power density: 30 dB removes 99.9%, 10 dB removes 90%.
- [Shielding verification](https://emfbase.com/protocols/shielding-verification): How to prove a shielding measure worked: identical instrument, position and source conditions before and after, reported in dB as well as in absolute units.

## Sources

- `sbm-2024` Institut für Baubiologie + Nachhaltigkeit (IBN) (2024). *Building Biology Evaluation Guidelines for Sleeping Areas (SBM-2024)*. https://buildingbiology.com/site/downloads/SBM-2024_EVALUATION_GUIDELINES_EN.pdf — ngo, link checked 2026-08-12

Data licence: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Dataset version 2026.08.1. Retrieved from EMFBase, https://emfbase.com.

This record is reference data, not medical or legal advice. Regulatory limits, scientific guidelines and precautionary values are labelled separately and answer different questions.