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Re: What has everyone got against PCB?



Hi all

Just a precision when PCB burn at the right temperature fork they produce
furane highly toxic and worse dioxins one of the worse toxic know.

Luc Benard

Tesla list wrote:

> Original poster: "Jim Lux" <jimlux-at-jpl.nasa.gov>
>
> A bigger problem is substation accidents, and circuit breakers catching on
> fire. High power circuit breakers (unlike the ones in your house) need
> something to specifically quench the arc that forms when the contacts
> separate.  Lots of techniques are possible: magnetic fields, air blasts,
> physical high speed separation, and, relevant to this discussion, the blast
> of hydrogen gas formed from the decomposition of the oil by the heat.
> Since the container is mostly sealed, there isn't any oxygen to react with
> the hot hydrogen, and the arc gets blown out very nicely. HOWEVER,
> containers aren't perfect, the oil level might be a bit low, etc.  Now
> you've got an arc, hot oil, hydrogen, and a fire.  THen the circuitbreaker
> next to the one that caught fire catches fire, etc,etc.etc....
>
> In Europe, where the packing density of civilization is much higher, this
> was a real problem, partcularly when bombs are falling... Electrical
> installations being a good target for bombing, and having them full of
> flammable oil just makes them more attractive.. Air blast CBs have the
> problem of the supersonic gas flow being quite loud, even with mufflers.
> Gas Insulated Switchgear (GIS) using SF6 has largely replaced oil
> switchgear in dense areas.