Original poster: "Terry Fritz" <twftesla-at-qwest-dot-net> Hi Richard, Here is a chart: http://www.isi-seal-dot-com/Technical_Info/Tech_Dielectric_Strength.htm Depends on the gas, stray radiation, and I believe the electrode materials. Cheers, Terry At 02:51 PM 2/6/2002 -0500, you wrote: >All, > >Does any one know the dielectric strength of vacuum? > >Sincerely >Richard Raynault > >