X-Message-Number: 9574 Date: Thu, 30 Apr 1998 23:11:23 -0400 From: Mike Darwin <> Subject: Dewars in sewars For some reason, people on Cryonet can't seem to leave well enough alone. John Bull was kind enough years ago to provide a pleasant dinner for me and a colleague which was a respite from a most unpleasant task: removing the badly decomposed remains of two cryopatients from a cryogenic dewar. I remember the dinner and John's kindness with gratitude, but I cannot let go uncorrected the following remarks which John posted here recently: >In Cryonet #9491 Paul Wakfer states "the amortized yearly cost of CI >storage is at least as high as that of CryoSpan and Alcor." Paul, have >you factored in the inevitable repair costs to these dewars? >My personal experience goes back to one bought in 1969 by a good friend >of mine, from Minnesota Valley and Engineering Co. It carried a ten year >guarantee (not much when you consider what it was to be used for). It >lasted just about ten years before losing it's vacuum. We had to remove >the bodies and haul it too a repair shop in the New York City area. The >"repair" lasted about two years. The second time we didn't get to the >capsule in time, the bodies thawed out and were later buried. The above is hardly the whole story, with which I am intimately acquainted, much to my regret. The dewar in question was indeed manufactured by MVE and it was a very fine piece of equipment. In fact, it withstood a degree of mistreatment I'venever seen any piece of cryogenic equipment withstand. The "friend" of John's was a man named Nick DeBlasio. Against all advice and common sense Mr. DeBlasio placed this fine piece of high vacuum equipment in hole in the ground in Mount Holiness Cemetery in Butler, New Jersey. The hole consisted of a room about 10' x 10' x 15' with a utility vault surface terminator. The water table is high in New Jersey and within a short period of time the dewar was standing in several feet of rank water. Despite this mistreatment, and despite having been transported on its side under rough conditionsbefore placement underground it continued to perform well. It continued to perform well, in fact, until a hammer was used to loosen the foam neckplug from the top of the dewar so Mr. DeBlasio could view his wife. The neckplug was frozen in plkace because of the high humidity environment and because it had been coarsely and inappropriately modified to allow for bulk filling (creating a huge heat leak adjacent to the necktube/foam neckplug). The hammering damaged the top weld -- no mean feat as this is a pretty rugged weld on this unit. I was impressed at the amount of stupidity and force required to achieve this when I had the opportunity to look over the unit -- after several hellish days of trying to remove two corpses whose skin had slipped off and which were frozen in a block of decomposition fluid in the bottom of the dewar. None of this need have happened. Mr. DeBlasio was advise by Curtis Henderson, by myself and by others at a public meeting that failure to have any kind of alarm system with a telephone dialer and to rely on routine, unsupervised bulk deliveries by a cryogenics firm was sheer insanity and doomed to failure. The second failure occurred while DeBlasio was away on vacation in Florida while the cryogenic company frantically tried to reach him by telegram ands telephone to tell him that a "bad odor" was coming out of the dewar. After the first failure DeBlasio was told by me that the repair company he used to effect the repair was not one to be relied on (they built the disastrously high boil off "King Kong" dewar purchased by Trans Time) and that the dewar should be carefully monitored under static operation for at least 90 days before being pout back into service. Finally, in any event, the notion of leaving patients sitting in a hole in the ground in a cemetery where they were checked on once a month in the absence of any qualified supervision was itself unacceptable and a recipe for _certain_ disaster. >CI's oldest fiberglass cryostat is eleven years old, has never been >repaired, and shows no sign of needing repair. Additionally while CI's >LN2 cost per patient may be higher than Alcor's and CryoSpan, this cost >per patient will come down as CI builds bigger cryostats. As far as I know, no one can come close to the performance records of MVE and similar _all stainless steel construction_ superinsulated dewars when handled intelligently. 2st Century Genetics (no relation to 21CM) in New Prague, MN has MVE equipment (big open mouth dewars) which have been in continuous service for nearly 30 years and have never needed re-evacuation. We have an MVE dewar at the lab here in Rancho which was purchased by Bruce Cohen for Negative Entropy circa 1968 and it is _still_ performing to specifications despite having been hauled across the country several times and used as a refill dewar -- still never having been re-evacuated.. PG-145s and LS-160's which are used to haul and deliver liquid are abused unbelievably by the delivery people and I can speak with confidence that no fiberglass dewar would take that kind of punishment any better. As to lifespan of high vacuum all stainless steel superinsulated dewars stored under reasonable ambient conditions (i.e., inside a building and not exposed to the elements) it can be presumed to be indefinite. By that, I mean literally several hundred years or more. The frequency with which these dewars need to be re-evacuated will vary depending upon the amount of getter and the quality of the initial workmanship (and in particular on the quality of the vacuum valve selected). For dewars made by MVE or the current manufacturer in Southern California I would guess vacuum life to be in the range of 30 to 60 years, minimum. Re-evacuating these dewars when they do need to be pumped down has gotten far easier. In fact, we have all the equipment to do so in-house including digital high vacuum gauge, valve operators, roughing and diffusion pumps. This hardware was picked up surplus for pennies on the dollar and is actually used for other applications in the lab. Superinsulated dewars can be made more secure against emergent failure by the expedient of placing them underground in heavily protected silos and wrapping them in high efficiency foam insulation (which serves as a back-up in the event of vacuum failure). This is the approach used by CryoSpan. I have toured the the CI facility. Every cryostat in operation there had a vacuum pump on it and required frequent re-hardening of the vacuum. This is acceptable where there is vigilance, as there appears to be at CI. But, it is another hassle. Further, the units CI currently use are very large and inefficient and must be stored above ground in a building which is vulnerable to storms (tornadoes)(which are increasingly unpredictable as to their range with increased global warming) and other means of attack. I do not wish to give the impression here that CI dewars are "bad." They work. They appear to be durable and they represent a different solution to the problem of storage. In the long run, large perlite or foam insulated containers make sense when large volumes of liquid/patients are to be stored. CI has chosen to develop this technology early on rather than later on. This may be a reasonable tradeoff given the skills and inclinations available to them. However, to imply that superinsulated vessels are unsafe, uneconomical or have a poorer track record is not justified. In particular, to associate Minnesota Valley Engineering (MVE) with production of anything other than a superior, indeed a superb product at a great price is to do a great injustice. The current Bigfoot-type design in use by CryoSpan, Alcor, and Trans Time was a the result of a great deal of careful thought on the part of a couple of top-notch MVE cryogenic engineers, myself, and Hugh Hixon of Alcor. I believe these dewars will stand the test of time. I believe MVE did a real service to the cryonics community by making the committment it did to manufacture these units when no one else was willing to. It was a direct result of Mr. DeBlasio's gross negligence, neglect and mishandling of MVE equipment (and his subsequent threats to sue MVE) that caused MVE to stop manufacturing human storage equipment. >Incidentally, the capsule I referred to was given to Mike Darwin and >could possibly be in use today? Last I heard it was in New Zealand and not in use, al thought it had been in service with Trans Time before the then. Mike Darwin Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=9574