Document YreR5OYQgNaVJkoOmaBm5R7M8

{ Jfuyu1* V'* ' '..4JP.IP!uf^WUWMjJp^... IJIJW IfBUyHMMP awLg*** Li*?20 95 rm^m btfcl -o LEAD INDUSTRIES ASSOCIATION 4S0 IXJUNGTON AVENUE NEW TO*K 17, M. . - fnmrjry 1952 s o b j x t i UBoiuionr e c s io e TOR HAKH.IIO RADIOACTIVE mmiiL! To Mabbare of the lead Industries Associations The Atonic Energy CornedIon and the Aaerican Inatitute of Archi tec ta co-sponsored a meeting for the purpose of reviewing laboratory design for handling rslioactiva materials In light of tha increased cornercial use of radioisotopes, lhe meeting, conduc ted by tha Building &earcb Advisory Board, was held at the f national Acadcoy of Sciences, Washington, D.C., on Kovoaber 27 and 28, 1951* The following are abstracts of the papers presented with aphasia on points brought out involving the use of lead, and therefore, may be of Interest to menbers of the lead In dustries Association, __ Very truly yours. Secratary ' (> weew^yawepiripr l JHIlpi'erwM1 * KT -1 -T I U I III.I,I '*1 V . r vrr itmY^-^-3, ^ UIJ*JI IIIIBILU^MIUP'"""--'--*>M LIA22096 6' 0 ARCHITECTURAL IKTROITCTIOS TO RAJIQCKDgCAL LABORATORT LAT-OUT - A. 0. Mackintosh, Oak Kidge Nationsi Laboratory The design of processing buildings and laboratories and Ux planning of largo planta for handling radioactive materials is one of tha newest fields In architectural endeavor, facilities for handling such materials fall Into two aaln categoriesi (1) High level chemical process plants requiring plant scale equipment and heavy bull shielding; (?) Laboratory facilities In which smaller quantities of radioactivity are handled for purposes of analytical control; development vork In the use of Isotopes In general Industrial, agricultural and medical applications; or development work at 1tonic fhergf CocelssIon sites, Tha design and construction of radiochenical laboratories la not vastly different nor more costly than that for a standard chealcal laboratory. Precise handling of a few new factors and greater attention to detail are the major requirements. Pure alpha end beta emitters can be easily shielded against but offer e serious hasard if tboy enter the body because of their greater loniration potential. Cams adb> ter* require shielding to protect the operator from radiation but are less hasardous than alpha emitters If lodged in the body. In addition to pirovldlng biologi cal protection, laboratories mist be designed to sd.niad.ie background radiation to vfclch sensitive exprariaental radiation lnstruaents ar exposed. 1 five general levels of activity may be encountered In commercial instal ls tlonsi (1) less than normal background (special radiation instrumentation), (2) normal background, (3) low activity ( tracer* .ork dealing with cicrocurle entrants of beta and gaoua activity), {It) alpha activity of varying Intensities, and (5) td.ddla leval activity where research work of a *warn* nature Is carried on (sdllicurie amounts of beta and gamma radiations). Vtriicuria amounts when handled in small quantities need not increase materially the complexity of laboratory lay-out. All that it required 1* close attention to details which ere commonly used in handling chenical toxic materials. Potential spread of activity cast be reduced by avoiding ths placement of hot" facilities directly adjacent to cold* facilities. If this cannot be avoided, sufficient shielding will be needed between the areas. For biological protection, shielding should be calculated to give a total Irradiation at tha surfoee of the shield of 6.5 wrep/hr- Flexibility Is of utmost importance in building lay-out and location of laboratory equipment) far more essential than In normal Industrial practice, for handling low activity levels such as in "tracer" work It is found that very little provision must be aide for these laboratories beyond that normally used in ary chem ical facility. For middle activity levels, the areas where radioactivity Is handlad ssjst be Isolated nainly to provide for centralised waste gas and liquid handling facilities, local shielding in the fora of lead brick enelosuras (usually 2* x li* X 8* bricks) serv# this purpose well. High level activity requires shleldir* of bulk or general material in addition to the local shielding. This general shield ing nay take the fora of a one or two foot thickness of solid eoocrete blocks, usually 1" x 6" x 16*. In areas for alpha operationa, glove boxes should be used Q to prevent Inhaling or Ingesting particles having this type of radiation. Host shields ere built to pirovide t radiation level of about 6.5 sr, p>er hour at the surface of the ahleld. Alpha radiation requires essentially no shielding. Beta radiation requires only thin plastic shielding less than 1 Inch thick in all cases. n.-- radiation requires more massive shielding thus necessitating excessive floor TT ,M' ayw i : N 1920.01 ywgr W i 11,,* LIA22097 iua .fl.j.iTewt.r.iWnA-H Iti iiWif-iaii'faer'nir -** loading In laboratory design to allow for the weight of shielding. Laboratory fur niture oust also be designed to carry unit shield loads. Sonewhere between 1,500 and ?,500 pounds of lead nay be stacked In an average hood. {standard bench tope cf naterlal similar to Chens tone are noraally quite acceptable. Soae operators prefe* tops of stainless steel. Roods can be built'of a variety of materials which should be protected lth a coating of a atrlppabla nature. Laboratory sinks nay be cf Alberene* tr vtalnleas steel. Ducts frea boode for low activity levels cao be brick. Inn or galvanlted and coated with a suitably corrosion resistant organic coating such as the numerous cocpound vinyl coatings avallabla on the aarket. 8talnlais steel due to are not necessary. Process wastes are collected froa all "cold* drain lines which have been chiefly of lead or Durlron but acceptance la bee cuing wore general now that they stay be of cast Iron or even galvanised so long as Durlron trspe are provided. Liquid waste Ir. the "hot* drain line should always be of atrInless steel without traps be cause of the build-up of activity which would take place at this point. In suesary, the factor of flexibility la of utmost lmportanea. The tech nique of using radioisotopes la new and concepts of applications of radioactivity are rnpidly changing. Site lay-out and laboratory design, therefore, mist be suf ficiently adaptable to changing ideas, AIR STTpm AKD F3KAIT3T HI IAB03A TORIES H\i.HLI.a RADIOACTIVE HlTtRIALS - Carlton P. Roberts, Vooriiees, talker, Foley and Seitn. 1 Installations which do not anticipate handling radioactive Baterials above tracer* level car. operate satisfactorily with conventional hood systems with pro vision fur uliirctc local filtration wheu, or If, required. Standardisation of design la paraaount and the ardular system of laboratory design lends itself most readily to standardization of all facilities including ven tilation. hodular design provides completely repetitive construction on a small unit basic. Each module or unit has the aaaa structure, s u m electrical system, plumbing ays tea and air handling system. The service tains end supply and exhaust duct eyateea tust be designed to serve a combination of nodules. Many labot alortae are currently being designed so that the air flows from all clean areas of the labor atory apaca and thence out through the hoods, filtering of this final arhnuat aay be accomplished with Chemical Warfare Service type filters or other dry filters. Occasionally, the exhaust duct work aey be washed down to remava entrained radio active particles. The supply air oystems are usually constructed of conventional materials, principally galvanized Iron. Stainlass steel has beet, u tillted to a great extant for exahust systems in laboratories of this type although Its use la difficult to Justify. Calbestos, lucoflox, Uscolite, Careyduct, aluminum and other materials offering resistance to corrosion sf various vapors have been reed oceasionelly. In eome instances where dilution was extensive galvanized Iron has been utilized. Where 0 underground masonry ducts have been utilised, concrete with and without Ajaorcnatlng, vitrified tile, and acid brick lined concrete ducts have beat considered adequate. *<| rw.evie "^ 11 R, V in HiP ii 1111. ^ Ljui|fC. in w>%jxnt1 mar u4tjff,wmusj"1j1H'jwsftHMy ^ v '***' -- LlA22098 COWPOl AND SHirtPIVa or ISOtOPrt rt KADlOACTIVt LAPCRATORIES . Nelson B. Oarddn, tinivcrsily of California Radiation Laboratory. The shielding snd control of radioactivity apparently hss been shifting fron the Dilute, Disperse snd Decontssdnate* (TEE) philosophy or the passing of eontaainetlon from one sres or group to another, to the "Concentrate and Contain* (CC) philosophy whereby the material la entrapped once and for all at the outset. Adherents of the CC philosophy prefer the ultimate reduction of radioactive con tamination areas to the glovo or nanipulator bcx. Such boxes are usually lead lined to protect the operators, the thickness of the lead depending upon the activity level. They are equipped with glove parts (low level activity) or reacts control devices (high level). Observation of the operations is through specially compounded leaded giars. tn certain cases, leaded glass windows up to 36 Inches thick are used consisting of 1-ln. plates of glass separated by a liquid aoil ins having proper op tical characteristics, Ventilation, air filterirg and waste disposal problems ars special control factors of the CC philosophy. At radiation energies up to five Billion electron volts (mev), J in. of lead shielding will reduce tlie radiation Intensity by one-half. Shipping contain ers, as a rule, provide sbout 2} In. of lead shiel ditig. The density of special lead ed glees wlndcws with liquid interlayers ranges from ti/10 to 7/10 that of lead. camuiATivs s h ieu d o RSsPrRtvsns Alpha Beta Causa Air 35 cm 37 ea Infinite Water O.OOti ea 0.05 ca 10 ca (1 nev) :i lluxlra* or No Penetration No Penetration 17 ca (2,5 aer) li ct (1 aov) Concrete 6.5 c b (2.5 nev) Lead 0.65 ca (1 aev) 1.5 ca (2.5 ev) .TOP-FACTS AND n.hlShTS FC?. RADIOACTIVE XA?QTAt o iit s - Jaoea 0. Terrill, Public j ETeaxV. ierVTca f * i Two tain schools of thought influence the eeloctlon of arterial* for sur faces and flnirhes of radioactive laboratories. One prefers to use cheep materills which way be fre;<iontly discarded end cheaply replaced such as strlppabie costings. The other favors the use of lnp-rvioua surfaces wldch can bo cloaned, readily <Wcontaalnsted and re-used ary tlao*. In above-grade Installations, high quality vinyl or rubber sheeting and asphalt tile with regular tile croont provide callsfectory flooring, tinoleua installed with water-proof ecr,nt is also satlitsctory where relatively dilute eorre sires will be used. For on-grade installations the only satisfactory flooring 0 our* to be grease-proof arjhalt tile in-tailed with a heavy coating of rqjiar tils cc*cent. Cleaning or ar>ring plaster or tilo aalls or partitions generates dust which is particularly undesirable where radioactivity ia pre.ent, Thla has rerulted in Uniting rocoenondatlons to the application of special air-dried coatings to con crete, wood and eetal surfaces and to pro-flniahcd partitioning. if?'1. ..iilKiuajw.iw,ai 'f y ti'i lu-iw'jgjuugr *> LIA22099 I iitfil IrYlVflT'''^^^-^ --'w----t^'aaav- ...-------1. .a-Vc-e^-y e *l" k suitable wall consists of coocrets block bases covered by ts*o coats of Pruf Cost, Xmercoat, or their equal, covered uy a special coating of atrlpper baaa over which a peelable surface si; bo sprayed in areas of potential contamination. Ordinary paint finishes are generally too porous where contentnation Is possible. Masonite, plywood and natal sheeting ean all be treated with dec^ntaalnabla paints, stripper base and strlppabls coatings. Strlppabla coatings in solvent carriers are generally applied with spray guns. They have vinyl polymer bassa and comparable ctonical resistance with vinyl paints. * Ksny of the older laboratories designed to handle radioactive Isotopes j Installed stainless steel.bench tops. Mow both testa and experience have shown that other and sore sasily obtainable materials nay be even better. Some stainless steel bench tops have become stained and rough and difficult to decontaminate, fewer a toriala Include JLlberene protected with a non-porous surface Baterial, teflon, porcelainlsed metal and polyethylene sheets. Stainless steel docs hrve the advan tage of being wore resilient and lest rigid and can be fabricated without sharp corners, thus facilitating cleaning. } DIS?r$.L Of H1DI01C7IVK T13P3 - E. C. fitter, Oeneral !2ectrie Co,. Schenectady, I.T, Two broad policies have been advocated for the disposal of radioactive wasteei (1) dotemlnation of the radioactivity of the waste solution below an ar bitrary lwcl and dispersion Into a largo volume of water (DED philosophy, see above) end (?) cenecntrcticn end confinement of the activity, ultimately dieposing of It by burial in waste lands ant in the ocean (CC philosophy, see above). feturo-coda radioactivity has always been present In normal ground waters end other natural materials. In abundant source of beta activity is potassium due to tho presence of a radioactive Isotope Therefore, vegetable and anlr.al tissue furnish e surprising amount of radioactivity bocanse of the 1 content. Carbon lb, a radioactive isotope of carbon. Is even more Cocoon. *Xt Is evident, then, that we live la a sea of low level activity over which vc have no control.* iry type of radioisotope can be burled In the earth If it it dllutod with a non-radioIsotope of tho same element. In the same chemical form. Tho burial Is made In suitably selected areas and at a minimum depth of 5 foot. Sadlolodlns may bo discharged Into tho aaln scucr provided that It be discharged concurrently with potassium iodide so that the radioIodine dll be diluted to 10 nicrocurici per liter. Radiophosphorus may bo discharged into tho scucr provided that it la diluted to 1/10 mlcrccurle p>~r liter with stable phosphorus as phosphate. In each case, appropriate radiation surreys must bo carried out before rc airs are r-adc to tho pliablng and disposal ouCLcta to the main sc.ror. Of courso, tho sewage oust not enter dlrocUy Into tho fresh water systems. Radiocarbon may bo exhausted Into tho air provided that no parson shall bo closed to the Inhalation of air containing greater than .01 slcrocurlos per liter and that particulate natter be filtered from tho exhauet air. Dots and ga.-*- activi ties may be disposed of in alkaline flushes not to exceed 5 nicroc'urlcs per flush and 50 microcurios pr wook. liany radioactive elements can bo precipitated either alone or alo< with closoly related olaronts and coagulated by tho ferric hydroxide. m  p a i.i 'PHiinj " ; J -w m -MUWW l u ^100 ^^,MtofciamaimJ>--m*UMaL^wki^maLtMHTn-i aiMViir i i i*i . I't i \ Q i 5- Ion exchange la another approach that haa been used. In general, thraa types of ion exchange aedia are availablei leolltcs (natural and aynthotlc)} ocld treated coals; and synthetic rosins, Prollainary experiments show that Individual radioactlvo elaaents and various mixtures flowing through combination of cation and anion exchange rosins could be completely reoovod from solution. A third method, that of evaporation, has proven to bo the most effective system of asperating radioactive material from laboratory wastes. The evaporation aystom now in uso at the Inn11a Laboratory consists of a flash pan, circulating pumpe, heat exchangers, separating tower and condonaor. Tho cost of evaporation. Including overhead and amortisation, ia about 11 cents per gallon. Laboratory com bustible na terini such as waste paper towels, strlppable coating, clothing, etc., ia charged into an Incinerator and burned in an oxygen enriched atmoaphero. Com bustible gases ! rc psrcu through a wet scrubber, glass wool filter and Chemical Warfare Service filter. Proceedings of this meeting will be published along with illustrations and discussions at some future date by tho Building Research Advisory Board, National Academy of Sciences, National Research Council, 2101 Constitution Avenue, N.7., Washington, D. C, "i 1 j *# '! 9