If charge build up within pipework caused by the flow of non-conducting liquids (such as solvents) over virgin PTFE is a problem, the first step to solving the problem can be the use of antistatic PTFE liner. The details of this material and its properties are dealt with more fully elsewhere. For the purposes of this discussion, it should be said that the antistatic version of PTFE will allow static charge to slowly migrate from the inner surface of the PTFE to the outer surface of the PTFE, and from there it will contact the steel outer housing. However, the charge has not yet reached earth and could still prove to be lethal. Nb. Although antistatic lined piping components have two conductive flare faces between each component, these will not serve to provide a satisfactory earth path for static charge. The resistance to the flow of electrical current is too large for them to be effective.
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