X-Message-Number: 21237 Date: Sun, 23 Feb 2003 09:56:24 -0500 (EST) From: Charles Platt <> Subject: John Bull / Incompletely Filled Dewars References: <> John Bull says he infers from something I wrote that Alcor does not keep its patients completely covered in liquid nitrogen. I would prefer Mike Perry or Hugh Hixon to answer this, but personally I can't imagine what I wrote that would have created such a totally misleading impression. I believe the approximate height of a bigfoot Dewar is 10 feet. Even after we subtract the thickness of insulation in the lid, this still provides ample coverage for a whole body during the slow boiloff that occurs. Boiloff does allow the level to fluctuate to some extent, but I do not believe patients are ever exposed to liquid-nitrogen vapor only. The head-down position provides protection against exceptional emergencies that have never occurred at Alcor. --Charles Platt Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=21237