H Division Progress Report (February 21 - March 20, 1962)

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A. General Ra marks 2. Bio loo v and Medicine -ration of he Alamo a Imprwed Liquid Scintillation liquid scintillation whole-body counter (Humco 11). which has been under design and construction for the pamt three ycarm, is now i n full operation. Inprovemcnts over the previous model arc about a possible to determine pure beta-emitting nuclides such asSr gO and P3* by means of bremsutrahlung at levels below 0.1 microcurie. These wtce not detectable with the old counter. The improvaments result primarily from the use of 16-in. diameter multiplier phototubes which permit a great increase i n optical efficiency, and from increasing the thickness of the liquid scintil1a:or t o 12 in., a value indicated as optimum by Monte C8rlo calculation # . The improved remolution and increased energy range of the new counter make it poa sib leto determine quantitatively am many as six nuclide# Bimultaneously. This cap8bil it y is especially important i n animal acperimantation on retention of radioactivity.since it permits a significant aavfng in the time and effort devoted t o animal care and measursarnt. To handle t h e increamed burden of daca processing resulting from multichannel operation, the instrument is aupplfed with autormrtic data recording and processing syrtamo. All r e ~ ults, including coded infonnat ion ident if ying and describing the subject, are recorded directly on IBH cards which are then procemsed by an IDU 7090 computer. "he cotnputer program# extend to fitting In addition it i m now cornputer plotting of primary data and least-squares functions.

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3/28 COVRTRXGHT, !hq 8-2 Pirst Aid of ionization chamber survey inatrumenta. The results have been written as a LA Report, which is now being processed. Assistance bas 81.0 given toK Division i n determining the number and location ' .'of area alarms, air rnonitorr, portal monitors, and hand and foot counterr for th. core test facility at Ten Site., # A health physics lecture was given a t Ten Site to the reactor,s operating personnel. The lecture coveted the monitoring infonnat ion A neutron runrey a t DP weat was made t o study the nectron t ne rgy tram PuPq and t o determine a factor to apply t o portable aurvey inrtrumentr being used in this area. on thia survey. A LAHS Report is being prepared

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CnB-11 is remodeling Room 201 a t DP West.This vork has required the removal of a larga amount of highly contaminated equiparant. By close cooperation bet men H-1. W - 11, and Zia crafts,this work was done with a minimum *read of contamination lifty - four LAUPRE I plutonium fuel elements Were transferred from Ten S it r toWing9 without incident. Eight elements reading 20 r/hr st 1 nuter were moved at a time, using a uranium shield. The highest dose received was 60 mrem. On arch19th a potential radiation incident was disc were d .,&- 8 t Ten Site in timto prevent it from becoming Wr aOU O.At 1 0 ~ 0 0a.m. Room 128 war given arc n tine alpha check, and found toI labor at or v coats when they checked out for lunch. High lave1 k clean. A t noon, the operators detected activity on their ia ct iv it y was found inthe room, which was traced to a cracked pla8tic bottle i n which a plutonium metallurgical rp8ciuun was stored. The area has been decontaminated, and new storage fac i lft its provided for the specimens. Urine ass8yr have ken scheduled for I Much time was apent monitoring and decontaminating Shop 4 i n and uaed on s ~ l lp ieces of tub alloy and or alloy. was rt art ed, no trouble was encountered from radioactive contaminBt ion. Reccntiy, with an increase in quantity of material, we beqan t o find contamination on the equipment and the men'r clothing. L t wan decided to move t h e opermtion to Shop 13, where protective clothing and rad-rafc surveys are routine. The required monitoring a11 equipment t h a t had been used, and decoataminating Soma time ago Lhe method-X machine was moved i n t o Shop 4 When the program A t D? Site GMX-7 has performed 80- dmtonations involving tubalby. The 0rmratlOn was checked for radiation health problems. 0- 3 -

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A i r samples taken flva o m - tenth the MPC: the minute. after detonation -re approximately walls of the chamber are cont8miruted. but tln nute rial does not kcom air bo-. On the basis of our t08tSr GCIX-? was 'cold t o go ahead with thir program. Numbor of Disabling Injuriem 4 I6 Nurkr of Days Iast 84 LB, 233 -re were no lomt time accidents during t h i 8 report pcriod. There were no fires a t the Laboratory during t h i 8 report D. Motor Vehicle Acc idcnt 6 Y l / 6 2 t o 3/1/62 1961 There were three G wer nmr nt vehicle accidents during February involving Laboratory drivers. One occurred while the driver warn backing, OM occurrod vhen a vehicle 6kidd.d on ice and hit a fence, and the other occurred when a LASL driver made aleft turn and struck 1. H-24 and --DO are continuing the SOP review of m - 7 procedure8 for HE work.

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following fill uw ro shown during 3. “ Sam Aspects of Beach and W8ter Safety ” was reproduced and distributed to Dominic personnel 4. Approximately 400 gallon8 of diethyl ether wro disposod of without u riou s incident. Tho ether had been i n atock many year. and thore was concern oyer the fornution of peroxides. 5. k, ms Yucca Safety Hanual is in preparation and portions will probably k distributed within a month. 6 . This office is working clomely with J-Division i n planning €or the Pacific Oporrtion. James G.Stearns left Loo Alamom on March 3rd t o be inn side nc eat Christmas Island asthe TU 8.1.1 Safoty M via or for approximately a month. A. tvaluation and Control worx b total of 47 air 08mphS and 4 * Wipe sampler were coll oct ed in the beryllium machine shop during this period: two of thore were # lightly above and other8 were wall bchw permissible air concen2rations. Other air and swipe uamplor were collected in were belaw permis8ible levels. Room air and stack air sampling was continued in the pomf ~ 8ibl elevels and all other samples wera woll below ruch 1OVOl8. OM room air concentration was slightly above

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In Shap 15, 29 breathing zone air samples were collected, of which several ware above permissible levelm. This study is continuing i n collaboration with Group €I-1. made t o ewaluate the factor of resuspension of settled dust particle.. Additional meamuremants a r e being Pour air samples were collected for TCE vapor during operation of the degreaeer i n the plating shop a t TA-22. All4 of then samples were vary close tothe maximum permissible concentration of 100 ppm. Additional studies will be made on this equipment. I Air sample6 for carbon monoxide we= collected at a 1 -f i ring pit of GKX-6 a t Ancho Canyon immediately after a ohot. Those samples shoved concentrations o € 300-600 ppm: however, within 5 minute. the carbon monoxide was cleared out of the pit by natural Air sampling for fallout continued on weekly bani8 with very law levelm being detected. Since the iodine concentration in milk samples i r now k low detectable levels,this mamplinq program will be discontinued until shortly before testing is rcmwd. Inipact noise level measurements were made i n the vicinity of the rolling mill a t the new Sigma Building. The levels found we,-. appreciably above tolerance levels for this type of noise and emr protectors have been i8sued to personnel. Another noima murvey was carried out inthe Plasmatron Room of the new Sigma Building, and these operators have now been scheduled for regular audiometric testing by Group H-2. Work is continuing i n an attempt t o reduce the noise level due t o the exhauat ventilation system in the graphite machine shop. A reduction of 3 db han been obtainad by the use of adaptora on t h e ends of the ducta.

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hranty-two person8 were fitted with respirator n in the test ch8-r during this period. An improved respiratory protective program has been discussed with Group Cl4P-5 and all individuals in that group are now beinq fitted with appropriate protect iva a quip m nt. Two hundred and four respirators that had been cleaned and presumably repaired were incrpected a t various locat ions throughout the Laboratory. Of these, 14% were found t o be unsafe for use: a detailed respirator maintenance program was drawn up and wb mitte d that respirator cleaninq and maintenance be t rann fer red to Group H-I. Work is continuing with Group H-l i n Shop 15 t o improve the exhaust ventilation system as well as the air sampling system inthi8area.Ventilation hoods have been checked at W Site., Graphic Arts, and SSite.Six set a of plans involving ven'ilation have been reviewed and appr wed during the month. Modifications of ventilation systems have been discuesed with personnel at S Site and TA-40. An investigation was started to determine the size distribution of the dust in the exhaust stack from the RaLa cell a t Ten Site. Air samples have been collected frm the exhaust stack using tha aerosol spectrometer and millipore filters.A preliminary an8ly.i ~ indicates that a large portion of this aerosol is hrger than 1 p, indicating that the high efficiency filters may be defective orthe bypass V8lVe may be corroded. on this system. Additional work will be done 1. A study has been completed an the effect of long-term (up to6weka) Btorage of refrigerated urine on plutonium recovery. NO laas of plutonium ha. been detected.

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2. Analymes of autopsy tis su cn for uranium and plutonium 8re continuing. There im little evidecrc of any build up of plutonium inthe ti8SUe8 of unexpomed pra on s as a result Of fall - out am had been reported elsewhete. resins has progressed tothe point whsre substitution of a n ion exchange rte p for the present solvent extraction in the routine plutonium procedure is being considered. Such a change ham numerous advantages. A eiinilar study is being MdC on uranium. A study of the behavior of plutonium on anion exchange 4.A study i n co-operation with Group H-4 i s being planned an the lung retention and tissue solubility of uranium carbide, using a xp a rim n tal animals. 5.Particle sizing for the purpose of calibration of sampling cyclones for spherical particle6 has been nsumed. silver nitrate,har been prepared and is kin9tested am a rramplinq medium €or iodine on t h e dmcga stack. A large case is being prepared which w i l l be completely cquipped with safety equipment necessary for working in areas with limited egress. This will be shipped t o the Nevada Te8t Site for use by the Safety Group there. This will include a safety belt, a The law background alpha counters now being used by t h e ! Laboratory Section have about reached the er.d of their normal life. A new COmp8Ct instrument for this purpose has been developed by P-1. The first model will be tested soon. and, r f successful, eight units will be prepared for use by the Laboratory Section. Industrial Hygiene Group", which wan avaf lable thmugh the Office of Technicdl Services, has been exhausted and many requests for copies are still bt.;ny received. our prennt :bwthoda, and new methodm have ken developed, a start in h ing made on preparing a new edition of this report. Since there have been numerous changes i n

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1. Air suaples collected or field tests nude for: Trich loroc thy len Uranium alpha activity Ammricium alpha activity Gross beta activity Plutonium alpha activity Thorium alpha activity Trich l oro acetic acid Uranium alpha activity Beryllium i n - tal ramplea Beryllium on wipm Plutonium alpha activity in tissue uranium i n tianue (flu or esc.1 lo bent content of proprietaries

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! a . ~ h .e lec tronic logic chassis and dens it om tor have in that it docs not cycle properly t o read out dens it iea. It M Y not b. possible to correct the trouble until W. Steger of P-1 returns from atrip. However, it is not yet operating pr0p.rj.y b. Measurementr t o determine whether the pUhe height l is a linear function of the energy i n NaI(T1) crystal. are .till continuing. Characteristic K radiation of el tmnt o are still being uncd a s sour'ces, but it was found that neveral elements caald not be irradiated at the same time without producing shifts in the pulse heights. A t the present counting rates, the spectrometer mystem appears t o be quite stable. Pulse height versum energy measuremants from 8 t o 93 K.v have been made with a Naf (T1 activated) crymtal, irradiating two element8 and then one element ata time with similar results. The response of the Nal (T1) crymtal appears t o be non-linear to photons. After correcting for non - linearity of the electronics,the response is about 8 per cent higher at40 Kev than a t 93 Uev and the response is abcut 10 per ccnC lower a t 8 Kev than a t 93 Kev. c. Som initial preparation of a talk on "The Health Phyricimt and Civil D.fen80" t o be given by E. Be mis at the annual Health Physics Conference i n June vas made so that an abstract could be written and Submitted. 2. Work Cm let ed set up i n the H-6 x-ray room i n order t o make mpectrum measure nr nt ~ and to make in tr in ric efficiency measurements on various scintilla tor ! .*.. M just n ants and check8 on the linearity of the system were made with the help of P - 1 personnel.

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b. The gam - ray opectmm emitted by a device a t S-Site was determined with t h e H - 1 400 channel analyzer which was taken out to the site and aat up. The neutron flux warn 8imultaneously measured w i t h several type. of instruments by H-1. Tk. purpose of thsa raaasurenwnts was to try to explain tha dimcrep8ncioa in resultm obtained by various inmtrumontm. c. Aid warn provided t o P-l and H-1 i n some problems of radiation rasamurement with thimble chamber. a t the GUX-11 phcrnrax machine. One of the primary difficulties was that the thin ble chambeym king used were unknwingly being irradi8t.d by mom of the electrons of the beam rather than by x-ray8 alone. completed a report describing the energy dependence of 8UKVOy 1. Work in Prosrc ss a. Work continues on t h e local clinmtological study. b. Work conti …