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LOS AWOS. NEW MEXICO b - OFFICE MEMORANDUM Telephone Exc We have given the most serious consideration and hard study to your memorandum of September 20. The attached memorandum analyzes the problem extremely well. Tire conclusions it presents are correct and unavoidable. these conclusions are also precisely stated. The basis for The only way we could conceive of exrending our production runs beyond 25 days, for the foreseeable future,isto forego developments which are essential for higher Intensities. down upon usthc wrath of ERDA and NCI. Such a course would bring It is conceivable that by next spring we will have made sufficient progress to reduce our development, maintenance and tune-up periods from 11 days to8 days. If this could be accomplished, I would then again ask the question whether you would be willing to give one x-ray fraction, on the 29th day after the start of each cycle, and thereby achieve a situation which would permit you to access patients at any time, other than during extended shutdowns. Enc: Memo Hagerman t o Rosen dated Sept. 2 2
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LOS ALAMOS SCIENTIFIC LABORATORY The subject ypo and its implications have heen studied by an ad hoc cow it tee comprised of th8signers of this memo. Our conclusion is that ifwe are t o increase the current by any significant amount the proposed schedule is unworknble. explored in late spring 1977. We note that the present working schedule (which should be used untfl mid 1977)has increased the length of production periods to a254ay span instead of the 14-day span presently in use; this increase waa made for the benefit of the Biamedical Channel program. Ke believe that the question should again be The primary considerations which must be balanced i n determining the dure tion of the development, maintenance, tune up, and facility improvement components of any schedule are: Tune up time required: i f we are t o produce a 100-pA bean of the requisite quality we must allow a t least five shifts (four shifts machine, one shift ex per hen tal area) €or tune up following a machine retune the experimental area following a short experimental area development period. a shutdovn for extensive maintenance or machine Improvement Xinor maintenance requires a fcw hours of tune up. !.faintenancc time: Routine preventative maintenance requires two 12-hour pri od spar morrth ufth an occasional longer period. The available personnel levels require that this work be scheduled during the normal Fork week. Our present experience show that One t o two hours are sufficient to Several days are necessary after Facility improvements: Ya j or facility changes may require several days to several weeks t o accomplish. These major changes will be done during the long shutdowns such a s our next December-January off perfod. improvements are frequently Installed during maintenance periods o r development periods. These trial versions are of ten recalcitrant and result In unexpected delays in the maintenance o r development period. Trial versions of -chine
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increasingly complex and require careful control of the hem during the experiment and careful analysis of the results, These experiments lead to new operating procedures, equipment change8 and software changes. evaluated in another experiment. work is insufficient to effectively use more than about a week of continuous beam time; this beam time should n o t be scheduled more frequently than every two to three weeks so adequate analysis time for the experlmental results is available. machine must be tuned up properly before these ex per in ents can start; further,these u per he nts frequently "destroy" the tune of the machine so it must be retuned b e f o r e production can The ex per hen to in this area are becoming A l l such changes must then be staff involved In this Exporfaental area development: Involve a significant overhead interns of re tuning ; of this develop ent work require When major improvements are required along the high-intensfty lines shutdown of two or more weeks vi11 be required, Same of this work does not special accelerator tunes. The above consideration forces us to conclude that4 - 1 / 2 day interruption for machine development, improvementr maintenance and tuning will be useless if one is t o increase current in the desired fashion: a loday period should he nearly optimum. We also caution that a major failure can occur a t any time in such a complex facility ; such failures could easily require several weeks Assoc. Div.At a der for Operations Joe Bergstepn, XP-2 Croup Leader