The Faraday cage: from Victorian experiment to Snowden-era paranoia
Michael Faraday’s pioneering work on electricity made him a 19th-century superstar. Now his signature invention is being repurposed for surveillance–proof bags, wallpaper and underpants – not to mention plot points in TV shows such as Better Call Saul
By Ian Sample
May 22 2017
There is not much room to build a box the size of a garage in the Royal Institution’slecture theatre. Tiered seating surrounds the large central table and leaves little room for much else. It was the same in January 1836, but Michael Faraday had no choice. He left his cramped lab in the basement of the building in London’s Mayfair and set to work. He put a wooden frame, 12ft square, on four glass supports and added paper walls and wire mesh. He then stepped inside and electrified it.
Faraday all but lived in the box for two full days. In that time, with electrometers, candles, and a large brass ball on a white silk thread, he explored the nature of charge. What he discovered transformed how scientists viewed electricity. But the cage itself was simply a means to an end, a way to insulate experiments from the outside world. It hardly screamed applications. Standing on the spot where the box was built, Frank James, the RI’s historian, gives the simple reason: “What was there to protect against electrical charge in 1836?”
Things have, as you would hope in nearly two centuries, changed. Today more than half a million sites found by Google refer to Faraday cages. They keep microwaves in microwave ovens and interfering radio waves out of hospital MRI rooms. Survivalists, with their knack for being distracted by peripheral threats, share tips on enclosures to block electromagnetic pulses that follow nuclear explosions. Companies offer Faraday bags, Faraday curtains and Faraday wallpaper that claim to stop mobile phone and wifi radiation, and shield devices from electronic snooping. In France, entrepreneurs are peddling radio wave-proof underpants. From the Netherlands comes a Faraday container that holds multiple smartphones. The aim is to break our gadget addiction and bring back good old face-to-face communication.
It is fair to say that not every product Faraday inspired lives up to its manufacturer’s claims. Metal mesh hats, scarves, shirts, socks, ponchos, hoodies, gloves, capes and leggings are all sold as shields for electromagnetic waves. As happens with clothing items, they have holes for arms, legs, heads and bodies, where waves can stream in. “It’s not a new thing, but more and more stuff is being developed. My personal opinion is that it doesn’t do a lot,” says Frank de Vocht, a senior lecturer in epidemiology and public health research at Bristol University. “There will be a lot of leakage because it’s not a Faraday cage.”
The market for the clothing has grown with recognition of electromagnetic hypersensitivity, or to unroll its official name, idiopathic environmental intolerance attributed to electromagnetic fields (IEI-EMF). Those affected believe that ubiquitous electromagnetic (EM) waves are to blame for what can be genuinely awful symptoms. But studies point to another cause: placebo’s evil twin, nocebo. Just as positive expectations can turn a sugar pill into a painkiller, so negative ones can provoke real ailments. Metal mesh clothing is not the antidote. It reinforces the belief that electromagnetic waves cause illness and can make matters worse.
In the Netflix show Better Call Saul, Jimmy McGill’s brother, Chuck, suffers from electromagnetic hypersensitivity, and turns his home into an improvised Faraday cage, using tinfoil and space blankets. An earlier TV reference came in the long-running drama Lost, which featured a time-travelling physicist called Daniel Faradayand inspired fan theories that the crashed airplane and parts of the island had acted as Faraday cages.