The gas used in Plasma TVs is a mix of two non-flammable, inert gases, neon and xenon, both of which are used in fluorescent lighting. These gases are not harmful, either individually or when combined.
Do Plasma TVs Leak Gas And Need Periodic Recharging?
Each individual cell in a plasma panel is permanently sealed when the panel is manufactured. The entire plasma panel is sealed as well. Because the gasses are sealed inside a seal, Plasma TVs can not leak gas and do not need to be refilled or recharged. This is true if the TV's panel is broken, it is not possible for the gasses contained during manufacturing to be transfered into the environment.
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