Original poster: "huil888" <huil888@xxxxxxxxxxxx> Terry - Good to see some "expert" data .....Interesting that the thorium emission rate (assumed to be directly proportional to ablation rate) is 30X higher in an AC arc vs a DC arc. In all welding work, the arc is tungsten electrode to metal workpiece, where in an RSG the arc is typically tungsten-to-tungsten. Does a tungsten-to-tungsten arc further increase the thorium emission rate?
Also, the current the RSG electrodes see in medium-to-large Tesla coils is much greater than typically seen in TIG welding. However, where the TIG welder is seldom further than 24 inches from his torch, I think the typical observation distance from the RSG in a large coil is more like 24 feet .....
Regards, Scott ----- Original Message ----- From: "Tesla list" <tesla@xxxxxxxxxx> To: <tesla@xxxxxxxxxx> Sent: Sunday, February 11, 2007 8:08 PM Subject: RE: Tungsten,2% Thoriated or Pure?
Original poster: Terrell Fritz <terrellfone@xxxxxxxxxxxxxxxxxxxxxxx> The amount of radioactivity is not considered high enough to kill... http://www.hps.org/publicinformation/ate/q1593.html Cheers, Terry At 03:40 PM 2/11/2007, you wrote:Original poster: "Godfrey Loudner" <ggreen@xxxxxxxx> How do welders protect themselves from thoriated welding rods? Godfrey Loudner Original poster: David Speck <dave@xxxxxxxxxxxxxxxx> Joe, The objection to the use of thoriated gap elements is that thorium is a naturally radioactive alpha particle emitter. There is a small but measurable amount of gap erosion during TC operation, with some of that electrode material being converted to fine airborne radioactive dust. I think that many coilers are willing to sacrifice a small amount of gap efficiency to reduce the risk of lung cancer. Dave