ASTM C1473-2011 Standard Test Method for Radiochemical Determination of Uranium Isotopes in Urine by Alpha Spectrometry《α光谱测定法放化测定尿中铀同位素的标准试验方法》.pdf

《ASTM C1473-2011 Standard Test Method for Radiochemical Determination of Uranium Isotopes in Urine by Alpha Spectrometry《α光谱测定法放化测定尿中铀同位素的标准试验方法》.pdf》由会员分享，可在线阅读，更多相关《ASTM C1473-2011 Standard Test Method for Radiochemical Determination of Uranium Isotopes in Urine by Alpha Spectrometry《α光谱测定法放化测定尿中铀同位素的标准试验方法》.pdf（5页珍藏版）》请在麦多课文档分享上搜索。

1、Designation:C147305 Designation: C1473 11Standard Test Method forRadiochemical Determination of Uranium Isotopes in Urineby Alpha Spectrometry1This standard is issued under the fixed designation C1473; the number immediately following the designation indicates the year oforiginal adoption or, in the

2、 case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method is applicable to the determination of uranium in urine at levels of de

3、tection dependent on sample size, counttime, detector efficiency, background, and tracer yield. It is designed as a screening tool for detection of possible exposure ofoccupational workers.1.2 This test method is designed for 50 mL of urine. This test method does not address the sampling protocol or

4、 samplepreservation methods associated with its use.1.31.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the re

5、sponsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards: ASTM Standards:2C859 Terminology Relating to Nuclear MaterialsC1000 Test Method for Radiochem

6、ical Determination of Uranium Isotopes in Soil by Alpha SpectrometryC1163 Practice for Mounting Actinides for Alpha Spectrometry Using Neodymium FluorideC1284 Practice for Electrodeposition of the Actinides for Alpha SpectrometryD1193 Specification for Reagent WaterD3084 Practice for Alpha-Particle

7、Spectrometry of WaterD3648 Practices for the Measurement of Radioactivity3. Summary of Test Method3.1 A urine sample with232U tracer solution added is wet-ashed with nitric acid and hydrogen peroxide to destroy organicmaterial. The uranium-bearing solution is converted to a hydrochloric acid medium.

8、 Uranium is absorbed on an anion exchangecolumn from a 9 M hydrochloric acid solution and eluted with 0.1 M hydrochloric acid solution. The separated uranium is preparedfor alpha spectrometric measurement either by electrodeposition onto a metal disk or coprecipitation with neodymium fluoride andfil

9、tration onto a membrane filter.4. Significance and Use4.1 This test method is used to detect possible exposures to uranium isotopes from occupational operations.5. Interferences5.1 The presence of232U in the urine sample will be masked by the tracer addition. The alpha energies of233U and234U cannot

10、be fully resolved by alpha spectrometric measurement. A table of uranium isotope alpha energies is given in Appendix X1. Ifneptunium is present in the sample in the plus four oxidation state, it will coelute with the uranium.6. Apparatus6.1 Alpha Spectrometry SystemRefer to Test Methods Method C1000

11、, , and Practices C1163, D3084, and D3648 for guidance.1This test method is under the jurisdiction of ASTM Committee C26 on Nuclear Fuel Cycle and is the direct responsibility of Subcommittee C26.05 on Methods of Test.Current edition approved June 1, 2005. Published June 2005. Originally approved in

12、 2000. Last previous edition approved in 2000 as C147300. DOI: 10.1520/C1473-05.Current edition approved Feb. 15, 2011. Published February 2011. Originally approved in 2000. Last previous edition approved in 2005 as C1473 05. DOI:10.1520/C1473-11.2For referencedASTM standards, visit theASTM website,

13、 www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.1This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication o

14、f what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considere

15、d the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.6.2 Electrodeposition Apparatus Refer to Practice C1284 for guidance.6.3 Neodymium Fluoride PrecipitationRefer to Test Method Refer to Practice C1163 for guidance

16、.6.4 Borosilicate Beakers or Flasks, 250 mL.6.5 Borosilicate Beakers, 150 and 250 mL.6.6 Borosilicate Graduated Glass Cylinders, 5, 25, 100, and 1000 mL.6.7 Ion Exchange Columns, disposable polypropylene, with polyethylene frit, $5-mL capacity.6.8 Ion Exchange Column Reservoir, funnel, polypropylene

17、, 100-mL capacity.NOTE 1See Fig. 1 for a typical ion exchange column-reservoir setup.7. Reagents7.1 Purity of ReagentsReagent grade chemicals shall be used in all tests. Unless otherwise indicated, it is intended that thereagents conform to the specifications of the Committee on Analytical Reagents

18、of the American Chemical Society, where suchspecifications are available.3Other grades may be used, provided it is first ascertained that the reagent is of sufficiently high purityto permit its use without lessening the accuracy of the determination.7.2 Purity of WaterUnless otherwise indicated, ref

19、erences to water shall be understood to mean reagent water as defined byType III of Specification D1193.7.3 Reagent purity shall be such that the measured radioactivity of blank samples is minimized.7.4 Anion Exchange ResinAnalytical grade, Type 1, 8 % cross linked, 100-200 mesh, chloride form.7.5 H

20、ydrochloric Acid (9 M)Mix 750 mL of concentrated HCl with water and dilute to 1 L.7.6 Hydrochloric Acid (sp gr 1.19)Concentrated hydrochloric acid (HCl).7.7 Hydrochloric Acid (0.1 M)Mix 8.3 mL of concentrated HCl with water and dilute to 1 L.7.8 Hydrogen Peroxide (30 %).7.9 Nitric Acid (8 M)Mix 500

21、mL of concentrated nitric acid with water and dilute to 1 L.7.10 Nitric Acid (sp gr 1.4)Concentrated nitric acid (HNO3).7.11 Uranium-232, standard solution.48. Hazards8.1 WarningAdequate laboratory facilities, such as fume hoods and controlled ventilation, along with safe techniques mustbe used in t

22、his procedure. Site-specific policies for the handling of biological materials must be adhered to. Extreme care shouldbe exercised in using hydrofluoric and other hot, concentrated acids. The use of proper gloves is recommended.9. Sampling9.1 Collect the urine sample in accordance with the site-spec

23、ific protocol.3Various column configurations are available from Bio-Rad Laboratories, Life Science Group, Hercules, CA; Whatman LabSales, Hillsboro, OR; and Perkin Elmer LifeSciences, Akron, OH.3Reagent Chemicals, American Chemical Society Specifications, American Chemical Society, Washington, DC. F

24、or suggestions on the testing of reagents not listed bythe American Chemical Society, see Analar Standards for Laboratory Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeia and NationalFormulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville, MD.4Reagent Chemicals,

25、American Chemical Society Specifications , American Chemical Society, Washington, DC. For suggestions on the testing of reagents not listed bythe American Chemical Society, see Analar Standards for Laboratory Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeia and NationalFo

26、rmulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville, MD.4Such tracer radionuclides may be available from respective national standards laboratories as well as commercial vendors that provide radionuclides traceable to theirrespective national standards laboratories.FIG. 1 Typical Ion Exch

27、ange Column ArrangementC1473 1129.2 Preserve the urine sample in accordance with the site-specific protocol.10. Calibration and Standardization10.1If a traceable standard10.1 A232U solution is not available for use as a tracer, standardize a freshly prepared sample of232U; for guidance refer toPract

28、ice D3648. A232U standard may also be used to determine the detection efficiency of the a-spectrometry system which, inturn, can be used to calculate the chemical yield of each sample and the lower limit of detection (LLD) of this test method. Ustandard may be used to determine the detection efficie

29、ncy of the alpha-spectrometry system which, in turn, can be used to calculatethe chemical yield of each sample and the lower limit of detection (LLD) of this test method.11. Procedure11.1 Sample Preparation:11.1.1 Measure 50 mL of urine in a 100-mL graduated cylinder.11.1.2 Transfer the urine to a 2

30、50-mL beaker or flask.11.1.3 Rinse the cylinder twice with 5 mL of 8 M HNO3and add the rinsings to the beaker or flask.11.1.4 Add an appropriate amount of232U tracer solution to the sample (ca. 0.02 Bq or as prescribed in the site-specific protocol)and swirl the vessel to mix.11.1.5 Evaporate the co

31、ntents of the vessel to near dryness on a medium hot plate.11.1.6 Remove the vessel from the hot plate and cool for 1 min.11.1.7 Add 10 mL of concentrated HNO3to the vessel. Swirl to mix.11.1.8 Return the vessel to the hot plate and evaporate the solution to near dryness.11.1.9 Remove the vessel fro

32、m the hot plate and allow to cool for 1 min.11.1.10 Slowly add 10 to 15 mL of 30 % hydrogen peroxide to the vessel to cover the residue. Swirl the vessel to mix.11.1.11 Return the vessel to the hot plate and evaporate the solution to near dryness.11.1.12 Repeat 11.1.9 and 11.1.10.11.1.13 Return the

33、vessel to the hot plate and evaporate the solution to obtain a white sample residue.11.1.14 Remove the vessel from the hot plate and allow to cool for 1 min.11.1.15 Add 10 to 15 mL of concentrated HCl to the vessel and swirl to mix.11.1.16 Return the vessel to the hot plate and evaporate the solutio

34、n to near dryness.11.1.17 Remove the vessel from the hot plate and allow to cool for 1 min.11.1.18 Repeat 11.1.15-11.1.17 twice more. Proceed to 11.1.19.11.1.19 Add 75 mL of 9 M HCl to the vessel and heat gently to dissolve the residue.11.1.20 Remove the vessel from the hot plate and cool to room te

35、mperature.11.2 Anion Exchange Separation:11.2.1 Measure 3 mL of settled, water slurried anion exchange resin.11.2.2 Place a 250-mL beaker under an empty column. Transfer the resin to the column with water. Allow the water to drainfrom the column.11.2.3 Insert a glass wool plug on the top of the resi

36、n bed.11.2.4 Pour 30 mL of 9 M HCl into the ion exchange column reservoir and allow the acid to drain through to condition the resincolumn.11.2.5 Transfer the sample solution to the ion exchange column reservoir. Pass the sample solution through the resin column.11.2.6 Rinse the sample vessel with 1

37、0 mL of 9 M HCl and add the rinse to the column reservoir. Repeat the rinse once andallow the solution to drain to the top of the glass wool plug.11.2.7 Wash the resin column with 30 mL of 9 M HCl and allow the acid to drain from the column.11.2.8 Remove the beaker containing the combined wasterinse

38、 and wash solutions from beneath the resin column. Discard thecombined solutions in accordance with the site-specific disposal requirements for acids.11.2.9 Place a clean 150-mL beaker under the resin column.11.2.10 Elute the uranium from the resin column by pouring 50 mL of 0.1 M HCl into the colum

39、n reservoir and allowing it todrain through.11.2.11 Place the beaker containing the eluted uranium on a hot plate and evaporate the solution to just dryness. Remove thebeaker from the hot plate and cool for 1 min.11.2.12 Add 2 to 3 mL of concentrated HNO3to the beaker.11.2.13 Repeat 11.2.11 and 11.2

40、.12 until the residue is white.11.2.14 Remove the beaker from the hot plate and cool for 1 min.11.2.15 Add 5 mL of concentrated HCl to the beaker and evaporate to dryness. Remove the beaker from the hot plate and coolfor 1 min.11.2.16 Repeat 11.2.15 twice more.11.3 Electrodeposition or Neodymium Flu

41、oride Precipitation:C1473 11311.3.1 For electrodeposition, refer to Practice C1284.11.3.2 For neodymium fluoride precipitation, refer to Test MethodPractice C1163.11.4 Alpha Spectrometry Measurement:11.4.1 Measure the sample overnight (1000 min) or longer in an alpha spectrometry system.11.4.2 Measu

42、re the background and reagent blank activity for the regions of interest. Correct each uranium isotope activity forbackground and reagent blank activity.12. Calculation12.1Refer to Test Method C1000 for calculation of activity.12.2Calculate the lower limit of detection (LLD) in becquerels at the 95%

43、 confidence limit, as follows, assuming equal countingtimes for the background and sample:(1) LLD95%52.7114.66SBY!Tb!E!12.1 The activity of each uranium isotope is calculated as follows:Xi5 CiAt!/CtVs! (1)where:Xiwhere:SBXi= standard deviation of the detector background for the region of interest, c

44、ounts, concentration of a uranium isotope inBq/L,TbAt= background counting time, s, activity of the yield tracer added in Bq,YCi= radiometric yield of the uranium-232 tracer, and net sample counts in the energy region of the uranium isotope beingmeasured,ECt= counting efficiency for the alpha spectr

45、ometry sample counts in the energy region of the uranium-232 tracer,andVs= volume of the sample aliquant in litres.12.2.1Typical values for these parameters are as follows:12.2 The fractional counting efficiency of the alpha spectrometer, E, must be determined if it is desired to calculate the chem

46、icalyield for uranium. Calculate the fractional efficiency as follows:(2) E 5 RsA stdwhere:Rs= net counting rate of the standard source in the region of the alpha emitter(s) of interest in cps, andAstd= activity of the standard source in Bq at the time of the count.12.3 Calculate the fractional chem

47、ical yield for uranium as follows:Y 5 Ct!/TAtE! (3)where:TABLE 1 Summary of Precision and Bias DataSample TypeBlind Quality Control ReferenceNumber of analyses 103 140Concentration234U(BqL1) 0.17 0.025Precision, % 30 11Bias, % 4 1.5Concentration238U(BqL1) 0.042 0.058Precision, % 20 15Bias, % 7 6Reag

48、ent BlanksNumber of analyses 80mean 6 SD234U 0.0007 6 0.0013238U 0.0008 6 0.0013C1473 114SBT= 1 count per 60 000 s, counting time in s,TbCt=Ts= 60 000 s, the net sample counts in the energy region of the uranium-232 tracer,YAt= 75 % (0.75 in the preceding LLD calculation), and activity of the yield

49、tracer added in Bq, andE = 30 % (0.30 in the preceding LLD calculation).fractional counting efficiency of the alpha spectrometer.12.4 Refer to Practice D3084 for the Minimum Detectable Concentration (MDC), critical level, and uncertainty calculations.13. Precision and Bias13.1 PrecisionReplicate reference samples, blind quality control (QC) samples, and reagent blanks were analyzed at theWestinghouse Savannah River Company Radiobioassay Laboratory. These analyses were performed over a 12-month period byseveral analysts as blind samples in t