A Faraday cage is a closed metal container that helps shield small backup electronics from electrical surges. It is an optional, low-cost project.
What you need
A galvanized metal trash can with a tight lid, cardboard or foam to line it, and metallic HVAC foil tape (not regular duct tape).
How to build it
- Line the inside walls and bottom with cardboard so nothing touches the metal.
- Wrap each device in more cardboard or foam and place it inside.
- Close the lid and seal the gap all the way around with foil tape.
How to test it
Put a small AM radio inside, tuned to a clear station, and seal the lid. If you can still hear it, the seal is not complete. Add tape and test again.
What to keep inside
A spare weather radio, flashlights, extra batteries, a spare phone with offline maps, and a USB drive with copies of important documents.
This is an extra step. Water, food, medicine and a family plan come first.