X-Message-Number: 2114 From: whscad1!kqb (Kevin Q Brown +1 201 386 7344) Subject: CRYONICS Ettinger Reply Re: CI Cryostats Here is the latest reply to recent CryoNet messages from Robert Ettinger. Kevin Q. Brown INTERNET or ----- April 12, 1993 From: R. Ettinger To: Steven B. Harris & Correspondents, via good offices of Kevin Q. Brown > Subject: Cryonics Institute Cryostats Dr. Harris is misinformed on some aspects of CI cryostats, as shown in his posting of April 7. [ Msg #2072 - KQB ] We are not interested in selling them, or in persuading others to use them, but we do want potential members, as well as critics, to get the right information. First, they do not have to be pumped continuously. There is substantial outgassing, requiring initial pumping continuously, if you want optimum vacuum, but the need gradually diminishes. After a year or two the pump needs to be run only occasionally, less and less frequently. And if you don't run it for a while, you just get a gradual creeping up of the pressure. Second, if a pump fails, or if power fails, there is no emergency or even loss of vacuum. We have solenoid valves in line which close if pumping stops. And the pumps themselves have anti- suckback features. It is true that our construction costs have varied and are not known with great precision; but it is not difficult for a prospective user to estimate the cost of having one built by an estblished fiberglass fabricating company. You will find--at least in Michigan--that the cost of having one (rectangular) built for you is less than $5,000 per patient--same as our original estimate in 1976, or less!--if you make them large enough for at least three patients. This, as I understand it, is roughly the same as for MVE type units. (But if anyone is thinking of contracting one out, be sure to have a small model made and tested first, for your sake and that of the contractor. Some aspects of it can be tricky.) Each type has its advantages and disadvantages; we prefer ours for their greater ruggedness, lack of need for periodic baking and re-hardening, ability to be repaired in-house if necessary, lack of need for a high ceiling, and preservation of considerable insulation even if vacuum is totally lost. I think we are all impressed with Mr. Wowk's and Dr. Harris' indefatigable research and sprouting of ideas. The information from Polycold sounds promising, although backup would still be needed. ----- Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=2114