H Division Progress Report (August 21 - September 20, 1963)

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Uranium-735 plasma thermocouple pins were hand carried to Pacoima, California,by one of our Health Physics Surveyors. the plating of the U235 and found no contamination. from tha VICUU ~ and flu ah in q tanks were free from contamination. Ho monitored dur ln q Attho ALO Shelter Honagement Seminar held on September 18, one of the Section Leaders spoke on the train in q aspects of in st nxt ing the Lor Plamos shelter managers in radiological monitoring for civil dr fans e. Durinq the month afilm badge issued to a member of P-9 was found, on pro as sing,to have a density in mxcess o€ 5 € orthe DuPont 555 film. The densities of the Pins Grain Positive and NT A films ware not Uniform and wem not typical of those one would expect to find on film exposed to external penetrating radiation : that is, there was no evidence of a filter pattern for either the brass, cadmium, or open-windaw areas. I n addition, them was a complete lack of sqraemant between the three films whm evaluated from a Co60 curve. The following rerults were found: Component Film Cadmium t Brass r Open Window r Scanninq the fast - neutron film emulsion revealed no proton recoil track. above the nom1 backqround. Recorded ex tern81pen et rat in q radi - ation :evelr inthe work area for the period during which the film w.8 worn were a l l low. The films were examined by theH - 1health physicists, and all agreod that in their opinion the film did not ra present a true exposure t o external peru tr at I..,< radiation. It wa5 decided that the film would not be included in tho man's exposure record: however, a note givin q all of tho detail.has been placed in his medical mcord.

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With the a sri stan n of D - 8 , ir report was Prepared for the I!-4 Croup Leader de re rib in q rhe effects o f Co60 gamma radiation on Eiistman Tri - X Panchromatic Type 0glass p later.00th sensitometric and photographic data sha ing the effects of the Co60 gamma radiation were presented in the report.Several p hot qr a phi c exposures were made followed by varying expo sums to gamma radiation from a Cob' source. exparimant was to illustrate the combimd eff oct s of light plus radiation on a negative and printed photograph. The purpoae Of this A calibration of the new fila badge t o thermal neutrons from the then nal coluwn of the water boiler was completed. P comparison of this cal j oration to a ?ray calibration gave the sensitivity of the film filter 21 to be 0.703 r / rem. pray and neutron exposures were varied from 0.020 t o 1.000 r and rem in six approximately equal steps each, the y-ray exposure precmeding the neutron exposurea in every case. These films wore than evaluated for both neutron end y-ray exposures. rem 8:Id .2 rthe neutrori exposure evaluation is about twice. For value8 of .CS rem the results are much te tter, being about 25% low with .02 t and ioX high with 1.0 c . The results shad that for low exporvres The evaluation of tho sum of both exposures is very much better, baing about 20% lm with .02 rem and .02 r and within ? 10% for the rest. The data suggest that the prct-exposure Lo y-rays of increasing mnqnitude makes the mens it iv it y to neutrons qo try accordingly. P test with noutron exposure proceeding the p-ray exposure for a f e w films is proposed,

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Considerable time has hen spent on the Control for Radiation, Inc. (Con-Rad) Thermoluminescent Domimot r y System. Initially,the system did not work, primarily because the Lip pwder was not heinq heated to a high enough temperature. Pn adjurtmbnt was made of the copper finger3 which contact the planchet holdinq the p wdc r and through which the heating current flour. There was then an increase inthe amount of heating, but it still war not adequate. Pftcr cont acting the Con-Rad Co., it was determined that we had OM batch of stainless s tec i plan chet s sunt by th a company by mistake. The correct plan chet s heated properly and it appeare3 that the system would work. Althoyqh fairly consist an tre rul tr could n w be ob tai md, th8re seemed t o be difficulties in the el act rome ter - integrator circuit. The time constant associated with the in te gratin q capacitor circuit would vary in a peculiar but reproducible way.This is not an important effect unlesa i t is caused by a change i.n the capac it anca of the capacitor,in which case the calibration of the in at rum nt would chanqc. It might also portend circuit trou b lo8to corn. Therefore0 it waa decided that the cause should be determined before any calibration program was launched into. We are noy waiting tor a rep lae mant electrometer - tube unit to be delivered by the manufacturer. One hydrogen target ham been returned from Stanford and examined for electron beam damage: there appears t o be no change i n the target. The cell W LS hydrostatic ally pressured to rupture with the breaking point as previous lv tested. The run a t Stanford on the weekend of Sept em kr13 went very well. The next run will be i n November. The new target -11s have failed pressure tests and new designs are in A preliminary SOP on handling radioactive a our n shy LLSI. personnel8t the Atlantic Missile Range waa prepared and submitted t o the P-4 GrwJp Ceader, who in turn fo warded the SOP t o STL. This SOP was diacuased in detail with Pan-Am Environmental Control at Cape Canavaral and met with their approval.

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The radioactive gascs that may be present in the old trailer count aha are baing monitored by a qas sampler and two 10-mr ion chambers. To date, no activity has been obtcrved: however, t?w tot81 reactor operation in kuh has been less than 25% of the possible hh and the operating time has been almost continuously at low pw cr. Both of these factors tend t o keep concentrations of effluent gases Lou. Full-prrver operation occurred on Only two days, and on both doys thr wind was not from the south durin q the eveninq and night hours. Tho r e - mvslu8t ion of the nunbe? of neutron / t r8ck on NTA film exposed to neutrons in Bldq. 501at DO Bite was completed and a memo prepared on the results(NT A Film Badqe Response t o Pur4 The new Phsrmex machine is being operated on n more or l a s s reg s lar schedule.Afilm badqm ph n ted in the beam a t 170 ft. fran the target read 200 mr for a little over2 weeks exposure. We a m now routinely lookinq at a elected planted badges for neutrons. planted behind the berm6 and around the sides a € the igloo near the target end have all read zero for about 14 days exposure. %a only areas where significant levels of radiation are found artin and near the berm, within a few €&stof the target : mar the gun: and around the cavities inside the ig loc ? When WC8Saary, personnel -+e permitted to stay behind the berm during pulsing, provided they have solid communication with the control room and can be observed on W . So far, no radi8tion has hean Cate c ted at this position behind th berm. The control of the new machine area has been investigated and the3ossi bil it y of wandering personnel being able t o approach the area has ken con rid cm d. To get to the new machLne rite, pcrsonne1

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tothe GWK-11.Group Off it x and pick up :r. mxchanqe badge with attached key from the group =%:-r-*:Ly. The key i s used t o unlock the qate on the roaa ht we sn the office building and the new site. -fora the exchange badge and key are issued,the group secretary will call the control room for permissicn for the person t o enter the site. Per a cns could walk across Yotrilio Canyon Erm the CHX-4 and key must be obtained from their qroop secretary.A strand fane mn s from the GHX-4 nrea q ate south across Po trill o Cankon to the gate on the road to the mw Phennex machine. Ta approach the new site from th t east, one would hove t o pass through Kappa Site and climb up on the mesa and waik west through about amile o € rough country. Fny other approach from the south or east would require CKOSRing Water Canyon cr several miles of v e r y rough country. 1% seems, the?, th st either the proper badqe or a lot of ex arc is e is necessary to approach the area. Ma nhou rs Worked 4,607,007 6 ,a72,267 Number of Disabling Injuries 7 12 Number Of Days Lost 1.91 281 There were no d is abl in qin j url as to Laboratory personne I during this report pezioc‘. There were no Laboratory fires clurinq this roport period.

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E. Motor Vehic:c A cci dem 1/1/63 to 9/1/61 INumber of Accidents 14 16 There were two mmar vehicle accidents Eur i ~ ~Augunt. Loth were backing accidents. 9meting which included personnel from the Eq in cer in r ] Depart nant, -92, 14-3, a?iP groups concerned, was held to discuss installation of sprinkler systems at various Laborntory installations. f?.e Safety Office is workinq with the Dapartmtnt of Supply and Property on testing a proposed shipp in q container for f As sil u An a valuation was made of possible o it u at ion. necessitating F. Thvroid 119laholism in Children and Adults Us in q Very Snub11 Fallout 1''' can enter the food chain, deposit in the thyroid glands crC children and adults, and thus deliver a radiation dcse to this aman. T o estimate this dose, ret8ntion of roPioioflinu .!a a function of tine must be kncwn, but data for children are sc.icccI. k'e haw Ecveloped a very sensitive system especially for * ~ 8 ew ith neck. Thc double tra cor meLhod cnrrccts for uncertainties in the

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thyroid depth in the neck and also all wr retention measuremcnts t o be carried on for months. The crystal is the same type q ert uf ally used for whclc-body spectrometers with the exception that It has a thin entry window to admit the soft radiation. Results on 6apparently nosmal adults rhow radio iodine uptake ical half - times .weraqinq 103 Jays (ranqe 26 to 152 days). on 8app arc ntl v normal children show avorage rrdioioc!ine uptake a t 1 day is 20 percent (range 10 t o 2'1 per cent1 with biological half - times averaging 85 days (ranqt 57 t o 160 days). Thus, there is little if any difference between children and rd u lts in there two parameters of thyroid function. Of IL3' will produce a thyroid dose in children which i s larger than in adults simply because of the smaller gland weight in children. In addition,the cam only used uptake of 30 per cant is probably hiqh, 20 per cent being a better value. W e may conclude th8t equal in takes A.Evaluation and Control Work 1. Air Samolinq Studies During this pu rio d, 19 air sampler and 6 wipe samples for beryllium rete coLloct8d i n the beryllium shop, P-4 and ina pe n nir sib le levels. Air samples collected fer methyl chloroform in the breathing 20ne while machining tantalum vith methyl chloroform as a coolant indic s ted the air concentration was less thw; LOO ppm. Mercury vapor concentrations were moasured following spills in5di fie rent laboratories during this period. The laboratories were cleaned and no detectable mercury vapor warn found.

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Air sampler were collected for trailer during an unloadinq operation at gasoline p-red forklift truck in the trailer. The maxLmum concentration was 90 ppm and the averlrqe conant ration was 37 ppm. Previoum reports had indicated that the carbon monoxide concentration was above tolerance while unloading trailers. The safe warkinq levels for CO have been achieved by changes i n the unloading operation in relation to the use of the forklift truck. Two forklift trucks used a t SU-;O are equipped with catalytic exhaust pur if i oro which are SUppO8.d t o reduce the co concentration. During this period, a factory representative changed the catalyst in the cat8lytic muffler and did major service adj u o tmnt on the equipment, air sampler taken at the exhaust from the muffler after this chaye indicated a concentration of CO ranging from 5,000to6,000 ppe. This is approximately the sa- concentration found a t the exhaush from the muffler before the cat a lyn t was changed. W e have concluded that the catalytic exhaurt purifier does not reduce the CO concent ration to a reasonable Level and is considered inadequate. We will continue to collect routine air samples during this operation. If the CO concentration is found t o i,c above the thre3hold limit V81UC,portable exhaust blwess will lie used. 31c investigated thera - ting of beryllium metal with copper after the rata1 was heated ir. a furnace. The beryllium metal is coated by wing a paste of copper chloride. the operation WG conducted in a ventilated furnace and it Wafs not considered hazardous. Following an investigation where benzene is t o be used to clean a propane tank outdo ars, recommendations werc made for conducting the work and the operators were fit tod with prop or respirators. P.n invest i,.ation of the use or' carbon

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tetrachloride - U8d to clean mass spec to graphic components indicated that there is no exposurm to the operator since it was conducted i n an approved hood. We did recommand the use of a less toxic chlorinated hydrocarbon. namely, Proon-12 or tri chlo rot rif luoroeth8na. We in ve8t iq a ted and found no hazard i n the vacuum vapoyization and plating of Indium. The con c cnt ration of grljrs beta activity in the atmosphere remains low, and shored no significant ch8nge from the last report We have concluded our tests conducted during the Larr two months to determine the efficiency of Parr and A wr GhS s prc fil tc ra €or atmospheric dust. The filters located on the first and second floors of Hut Buildinq are used- to clean the building supply air. The test results indicate that the Anamlaas filter i8 slightly more efficient than the Parr oil coated metal filters.A report ha8 been prepared and fo worded to ENG-4 advising them of the results. Also, that the AnUtfilalS filters are rui tabla to rep lao …