>As far as the environmental impact of R-12 goes I really believe this is less
>"Enviro" and more "Mental" than anything else.  But that is my opinion.  It
>does seem strange to me that after using R-12 for all these years we happen
>to figure out it is bad for the environment at around the same time that
>Dupont's patent is getting ready to run out.

Patents last 17 years. R-12 was invented in the 30's or 40's. The patent is
long since expired.

There have been suspicions that CFC's were causing environmental damage
since the 70s, this isn't something that was discovered overnight, but
rather a mounting of scientific evidence that has shown a strong link
between atmospheric release of CFCs and decreased levels of ozone in the
upper atmosphere.

Joshua Van Tol -- jjvantol@uswest.net