1、Designation: D7784 12Standard Practice for theRapid Assessment of Gamma-ray Emitting Radionuclides inEnvironmental Media by Gamma Spectrometry1This standard is issued under the fixed designation D7784; 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 practice covers the quantification of radionuclidesin environmental media (e.g., w
3、ater, soil, vegetation, food) bymeans of simple preparation and counting with a high-resolution gamma ray detector. Because the practice is de-signed for rapid analysis, extensive efforts to ensure homoge-neity or ideal sample counting conditions are not taken.1.2 The values stated in SI units are t
4、o be regarded asstandard. The values given in parentheses are provided forinformation purposes only.1.3 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and heal
5、th practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2C998 Practice for Sampling Surface Soil for RadionuclidesD1129 Terminology Relating to WaterD3370 Practices for Sampling Water from Closed ConduitsD3648 Practices for the M
6、easurement of RadioactivityD3649 Practice for High-Resolution Gamma-Ray Spectrom-etry of WaterD7282 Practice for Set-up, Calibration, and Quality Controlof Instruments Used for Radioactivity Measurements2.2 Other Documents:PCNUDAT data files National Nuclear Data Center,Brookhaven National Lab, Upto
7、n, NY, USA3. Terminology3.1 Definitionsfor definitions of terms used in thispractice, refer to Terminology D1129.4. Summary of Practice4.1 Following sample collection, sample material is placedin a suitable container for analysis by a gamma spectrometrysystem. A suitable container is defined as a co
8、ntainer whichwill both hold the sample in a fixed geometry and for which thegamma spectrometry system has been calibrated. For solidsamples, the samples may be ground, sieved, or otherwiseprepared for the purpose of volume reduction, homogenization,or conformance to the calibration standard, as desi
9、red.5. Significance and Use5.1 This practice was developed for the rapid determinationof gamma-emitting radionuclides in environmental media. Theresults of the test may be used to determine if the activity ofthese radionuclides in the sample exceeds the action level forthe relevant incident or emerg
10、ency response. The detectionlimits will be dependent on sample size, countingconfiguration, and the detector system in use.5.2 In most cases, a sample container which is large indiameter and short in height relative to the detector willprovide the best gamma-ray detection efficiency. For samplesof w
11、ater or other low-Z materials (e.g., vegetation), there-entrant or Marinelli-style beaker may yield the best gamma-ray detection efficiency.5.3 The density of the sample material and physical param-eters of the sample container (e.g., diameter, height, material)may have significant consequences for
12、the accuracy of thesample analysis as compared to the calibration. For this reason,the ideal calibration material and container (often referred to asgeometry) will be exactly the same as the samples to beanalyzed. Differences in sample container or sample matrixmay introduce significant errors in de
13、tector response, espe-cially at low gamma-ray energies. Every effort should be madeto account for these differences if the exact calibration geom-etry is not available.5.4 This method establishes an empirical gamma-ray spec-trometer calibration using standards traceable to a nationalstandardizing bo
14、dy in a specific geometry selected to ensurethat the container, density, and composition of the standardmatches that of the samples as closely as possible. However, insome cases it may be beneficial to modify such initial calibra-tions using mathematical modeling or extrapolations to an1This practic
15、e is under the jurisdiction ofASTM Committee on Water and is thedirect responsibility of Subcommittee D19.04 on Methods of RadiochemicalAnalysis.Current edition approved Nov. 1, 2012. Published November 2012. DOI:10.1520/D7784122For referenced ASTM standards, visit the ASTM website, www.astm.org, or
16、contact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1alternate geometry.
17、 Use of such a model may be acceptable,depending on the measurement quality objectives of theanalysis process, and provided that appropriate compensationto uncertainty estimates are included. The use of such calibra-tion models is best supported by the successful analysis of amethod validation refer
18、ence material (MVRM).5.5 This practice addresses the analysis of numerousgamma-emitting radionuclides in environmental media. Thispractice should be applicable to non-environmental media (forexample, urine, debris, or rubble) that have similar physicalproperties. The key determination of “similar ph
19、ysical proper-ties” is the ability to demonstrate that the gamma spectrometrysystem response to the sample configuration is suitably similarto that for which the system is calibrated.5.6 For the analysis of radionuclides with low gamma-rayemission energies (100 keV), self-absorption of the gamma-ray
20、s in the sample matrix can have a significant adverse effecton detection and quantification. The user should verify thatinstrument calibrations appropriately account for any self-absorption that may result from the sample matrix.5.7 Commonly available energy and efficiency calibrationstandards cover
21、 the energy range of approximately 60 keV to1836 keV. Results obtained using gamma-ray peaks outside theefficiency calibrated energy range will have greater uncertaintynot accounted for in the uncertainty calculations of thispractice. Great care should be taken to review the efficiencycalibration va
22、lues and the shape of the efficiency curve outsidethis range. For greater accuracy in the analysis of radionuclideswhose gamma-ray energies are outside this range, a calibrationstandard which includes radionuclide(s) whose gamma-rayenergies span the energy range of radionuclides of interest isadvise
23、d.6. Interferences6.1 A list of some gamma-ray emitting radionuclides withrelevant data is provided, for information only, in Table 1. Thislist includes radionuclides which may be of interest to agenciesresponding to a large scale radiological event. Through inspec-tion of the list, it becomes appar
24、ent that there are numerousopportunities for interferences based on the gamma energyemissions. For this reason, it is important that the determina-tion of the presence of a given radionuclide be supported by allavailable evidence (e.g., additional gamma-ray emissions).6.2 The data provided in Table
25、1, Table 2, and Table 3 arenot mandatory and are provided for information only. Thecomposition of the nuclide library used by the laboratoryshould be matched to the analytical need and the data should bevalidated using a current reference source (e.g., LaboratoireNational Henri Becquerel, http:/www.
26、nucleide.org/DDEP_WG/DDEPdata.htm, or NuDAT data files, National NuclearData Center, Brookhaven National Lab, Upton, NY, USA)6.3 Several of the radionuclides listed in Table 1, Table 2,and Table 3 have x-ray emissions which may interfere withgamma-ray emissions, particularly below approximately 40ke
27、V. It is the responsibility of the laboratory to ensure thatx-ray and gamma-ray interferences are accounted for in theanalytical process.TABLE 1 Example of most likely radionuclides for emergencyresponseNuclide GammaEnergy (keV)Gamma Fraction Half-Life (d)Ac-227 100 3.17E-04 7.96E+03Ac-227 83.96 2.2
28、1E-04 7.96E+03Ag-110m 657.75 9.47E-01 2.50E+02Ag-110m 884.67 7.29E-01 2.50E+02Am-241 59.54 3.63E-01 1.58E+05Am-242m 49.3 1.90E-03 5.55E+04Am-243 74.67 6.60E-01 2.70E+06Au-198 411.80 9.55E-01 2.70E+00Au-198 70.82 1.38E-02 2.70E+00Ba-133 30.97 6.29E-01 3.91E+03Ba-133 355.86 6.23E-01 3.91E+03Ba-137m 66
29、1.62 9.00E-01 1.77E-03Ba-137m 32.19 3.82E-02 1.77E-03Ba-140 537.38 1.99E-01 1.28E+01Ba-140 29.96 1.43E-01 1.28E+01Bi-207 569.67 9.80E-01 1.39E+04Bi-207 1063.62 7.70E-01 1.39E+04Cd-109 24.95 1.43E-01 4.53E+02Cd-113m 263.7 6.00E-05 5.33E+03Cd-113m 23.17 6.00E-05 5.33E+03Ce-141 145.45 4.80E-01 3.24E+01
30、Ce-141 36.03 8.88E-02 3.24E+01Ce-143 293.3 4.34E-01 1.40E+00Ce-143 36.03 3.23E-01 1.40E+00Ce-144 133.53 1.08E-01 2.84E+02Ce-144 36.03 4.80E-02 2.84E+02Cf-252 43.4 1.30E-04 8.99E+02Cm-242 44.03 3.25E-04 1.63E+02Cm-243 103.75 2.08E-01 1.04E+04Cm-244 42.82 2.55E-04 6.61E+03Cm-245 103.76 2.30E-01 3.11E+
31、06Co-58 810.75 9.95E-01 7.08E+01Co-58 511 3.00E-01 7.08E+01Co-60 1332.51 1.00E+00 1.93E+03Co-60 1173.23 9.99E-01 1.93E+03Co-60 2158.7 8.00E-06 1.93E+03Cr-51 320.07 9.83E-02 2.77E+01Cs-134 604.66 9.76E-01 7.53E+02Cs-134 795.76 8.54E-01 7.53E+02Cs-136 818.5 1.00E+00 1.30E+01Cs-136 1048.07 8.00E-01 1.3
32、0E+01Cs-137 661.62 8.46E-01 1.10E+04Cs-137 32.19 3.70E-02 1.10E+04Eu-152 40.12 3.00E-01 4.64E+03Eu-152 121.78 2.92E-01 4.64E+03Eu-154 123.1 4.05E-01 3.11E+03Eu-154 1274.8 3.55E-01 3.11E+03Eu-155 86.45 3.27E-01 1.81E+03Eu-155 105.31 2.18E-01 1.81E+03Fe-59 1099.22 5.65E-01 4.51E+01Fe-59 1291.56 4.32E-
33、01 4.51E+01Gd-153 41.54 6.00E-01 2.42E+02Gd-153 40.9 3.20E-01 2.42E+02Hf-181 482.16 8.60E-01 4.25E+01Hf-181 133.05 4.30E-01 4.25E+01Hg-203 279.17 8.15E-01 4.66E+01Hg-203 72.87 6.40E-02 4.66E+01Ho-166m 184.41 7.39E-01 4.38E+05Ho-166m 810.31 5.97E-01 4.38E+05I-125 27.47 7.30E-01 6.01E+01I-125 27.2 3.9
34、2E-01 6.01E+01I-129 29.78 3.60E-01 5.73E+09I-129 29.46 1.90E-01 5.73E+09I-131 364.48 8.12E-01 8.04E+00I-131 636.97 7.27E-02 8.04E+00I-131 284.29 6.06E-02 8.04E+00I-131 80.18 2.62E-02 8.04E+00I-131 29.78 2.59E-02 8.04E+00I-132 667.69 9.87E-01 9.92E-02I-132 772.61 7.62E-01 9.92E-02In-114m 24.21 2.00E-
35、01 4.95E+01In-114m 189.9 1.77E-01 4.95E+01Ir-192 316.49 8.70E-01 7.40E+01D7784 1227. Apparatus7.1 Analytical Balance, readable to 0.1 g.7.2 Sample Containera container suitable for holding thesample material to be analyzed. The container may be of anysuitable configuration, but should be reproducibl
36、e in its dimen-sions and capacity. This should be the same container designfor which the counting system is calibrated. An ideal containeris smaller in diameter than the detector to be used for analysis(7.3) and should be as short in the vertical dimension as ispractical. A re-entrant beaker (e.g.,
37、Marinelli-style) may beTABLE 1 ContinuedNuclide GammaEnergy (keV)Gamma Fraction Half-Life (d)Ir-192 468.06 5.18E-01 7.40E+01K-40 1460.75 1.07E-01 4.68E+11La-140 1596.2 9.55E-01 1.68E+00La-140 487.03 4.30E-01 1.68E+00Mn-54 834.81 1.00E+00 3.12E+02Mo-99 140.51 9.09E-01 2.76E+00Mo-99 739.47 1.30E-01 2.
38、76E+00Na-22 511 1.80E+00 9.50E+02Na-22 1274.54 9.99E-01 9.50E+02Nb-94 871.1 1.00E+00 7.42E+06Nb-94 702.5 1.00E+00 7.42E+06Nb-95 765.82 9.90E-01 3.52E+01Nd-147 91.1 2.83E-01 1.11E+01Nd-147 38.72 2.30E-01 1.11E+01Nd-147 531 1.35E-01 1.11E+01Np-237 86.49 1.31E-01 7.82E+08Np-237 29.38 9.80E-02 7.82E+08N
39、p-237 95.87 2.96E-02 7.82E+08Np-239 103.7 2.40E-01 2.36E+00Np-239 106.13 2.27E-01 2.36E+00Pa234m 1001.03 5.90E-03 8.13E-04Pa-234m 766.6 2.07E-03 8.13E-04Pb-210 46.52 4.00E-02 7.45E+03Pm-145 37.36 3.86E-01 6.47E+03Pm-145 36.85 2.11E-01 6.47E+03Pm-147 121.2 4.00E-05 9.58E+02Pm-149 285.9 3.10E-02 2.21E
40、+00Pm-149 859.4 1.00E-03 2.21E+00Pm-151 340.08 2.24E-01 1.18E+00Pm-151 40.12 1.66E-01 1.18E+00Po-210 803 1.10E-05 1.38E+02Pr-144 696.49 1.49E-02 1.20E-02Pr-144 2185.61 7.70E-03 1.20E-02Pu-236 47.6 6.90E-04 1.04E+03Pu-236 109 1.20E-04 1.04E+03Pu-238 43.45 3.80E-04 3.21E+04Pu-238 99.86 7.24E-05 3.21E+
41、04Pu-239 51.62 2.08E-04 8.81E+06Pu-239 129.28 6.20E-05 8.81E+06Pu-240 45.24 4.50E-04 2.39E+06Pu-240 104.23 7.00E-05 2.39E+06Pu-241 98.44 2.20E-05 5.54E+03Pu-241 94.66 1.20E-05 5.54E+03Pu-241 111 8.40E-06 5.54E+03Pu-242 44.7 3.60E-02 1.41E+08Pu-242 103.5 7.80E-03 1.41E+08Ra-226 185.99 3.28E-02 5.84E+
42、05Ra-226 83.78 3.10E-03 5.84E+05Rb-86 1076.63 8.76E-02 1.86E+01Rh-106 511.8 2.06E-01 3.46E-04Rh-106 621.8 9.81E-02 3.46E-04Ru-103 497.08 8.64E-01 3.94E+01Ru-103 610.33 5.30E-02 3.94E+01Sb-124 602.71 9.81E-01 6.02E+01Sb-124 1691.04 5.00E-01 6.02E+01Sb-126 695.1 9.97E-01 1.25E+01Sb-126 666.2 9.97E-01
43、1.25E+01Sb-127 685.5 3.57E-01 3.85E+00Sb-127 473 2.50E-01 3.85E+00Sc-46 1120.52 1.00E+00 8.39E+01Sc-46 889.26 1.00E+00 8.39E+01Se-75 264.65 5.86E-01 1.20E+02Se-75 136 5.60E-01 1.20E+02Sn-113 391.71 6.42E-01 1.15E+02Sn-113 24.21 3.90E-01 1.15E+02Sn-123 1089 6.00E-03 1.29E+02Sn-123 1032 4.00E-04 1.29E
44、+02Sn-125 1066.6 9.00E-02 9.62E+00Sn-125 915.5 4.25E-02 9.62E+00Sn-126 87.57 3.75E-01 3.65E+07Sn-126 26.11 1.89E-01 3.65E+07Sr-89 909.2 9.50E-04 5.05E+01Ta-182 67.75 4.13E-01 1.15E+02Ta-182 1121.28 3.50E-01 1.15E+02TABLE 1 ContinuedNuclide GammaEnergy (keV)Gamma Fraction Half-Life (d)Tb-160 876.37 3
45、.00E-01 7.21E+01Tb-160 298.57 2.74E-01 7.21E+01Tc-99 89.6 6.50E-06 7.82E+07Te-127 417.9 9.93E-03 3.90E-01Te-127 360.3 1.35E-03 3.90E-01Te-129 27.77 1.64E-01 4.83E-02Te-129 459.5 7.14E-02 4.83E-02Te-129m 27.47 1.53E-01 3.36E+01Te-129m 27.2 7.80E-02 3.36E+01Te-131m 773.67 3.81E-01 1.25E+00Te-131m 852.
46、21 2.06E-01 1.25E+00Te-132 228.16 8.85E-01 3.25E+00Te-132 28.5 5.40E-01 3.25E+00Th-227 236 1.12E-01 1.85E+01Th-227 50.2 8.50E-02 1.85E+01Th-227 256.25 6.80E-02 1.85E+01Ti-44 78.4 9.47E-01 1.73E+04Ti-44 67.8 8.77E-01 1.73E+04Tl-204 70.82 7.40E-03 1.38E+03Tl-204 68.89 4.00E-03 1.38E+03Tm-170 84.26 1.0
47、0E-01 1.29E+02Tm-170 52.39 6.80E-02 1.29E+02Tm-170 51.35 3.60E-02 1.29E+02U-235 185.72 5.40E-01 2.57E+11U-235 143.76 1.05E-01 2.57E+11U-235 163.35 4.70E-02 2.57E+11U-238 48 7.50E-04 1.72E+12V-48 983.5 1.00E+00 1.61E+01V-48 1311.6 9.80E-01 1.61E+01V-48 511 9.80E-01 1.61E+01W-187 685.74 2.92E-01 9.96E
48、-01W-187 479.57 2.34E-01 9.96E-01Y-90 1760.7 1.15E-04 2.67E+00Y-91 1204.9 3.00E-03 5.85E+01Yb-169 50.74 7.81E-01 3.07E+01Yb-169 63.12 4.50E-01 3.07E+01Yb-169 49.77 4.22E-01 3.07E+01Zn-65 1115.52 5.08E-01 2.44E+02Zn-65 511 2.83E-02 2.44E+02Zr-95 756.72 5.48E-01 6.44E+01Zr-95 724.18 4.42E-01 6.44E+01T
49、ABLE 2 Example of most likely radionuclides for emergencyresponse subsequent to an incident involving a radiologicaldispersal deviceAlpha Emitters Beta/Gamma EmittersAm-241 Ra-226 Ac-227 P-32Cm-242 Th-228 Bi-210 Pd-103Cm-243 Th-230 Bi-212 Pb-210Cm-244 Th-232 Bi-214 Pb-212Np-237 U-234 Co-57 Pb-214Po-210 U-235 Co-60 Pu-241Pu-238 U-238 I-125 Ra-228Pu-239 U-Nat I-129 Se-75Pu-240 Ir-192D7784 123used to improve the counting efficiency for low Z-valuematerials. The container should be durable and sealable toprevent content loss during handling.7.3 Gamma-Ray Spectrometry Systemhigh
