Hazards
Bringing conductive materials or electronic devices close to a plasma globe may cause the glass to become hot. The high voltage radio frequency energy coupled to them from within the globe may cause a mild electric shock, even through a protective plastic casing. The radio frequency field produced by plasma lamps can interfere with the operation of touchpads used on laptop computers, digital audio players, cell phones, and other similar devices. Some types can radiate sufficient radio frequency interference (RFI) to interfere with cordless telephones and Wi-Fi devices several feet away.
If a tinfoil hat is placed on the globe, capacitive coupling can transfer enough current through the foil to give a small arc burn or light a small lamp connected to earth ground. This is possible because the globe's glass acts as a capacitor dielectric: the inside of the lamp acts as one plate, and any conductive object on the outside acts as the other capacitor plate. This is dangerous to do, can damage the globe, and presents a fire hazard.
Ozone, which is harmful to humans, may also accumulate outside of the surface of the glass orb after a few minutes of constant operation.
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