1、Designation: D5928 96 (Reapproved 2010)1D5928 18Standard Test Method Practice forScreening of Waste for Radioactivity1This standard is issued under the fixed designation D5928; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the ye
2、ar 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 NOTEEditorial changes were made throughout in January 2010.1. Scope1.1 This test method covers the screening for , , and r
3、adiation above ambient background levels or user-defined criteria,or both, in liquid, sludge, or solid waste materials.1.2 This test method is intended to be a gross screening method for determining the presence or absence of radioactive materialsin liquid, sludge, or solid waste materials. It is no
4、t intended to replace more sophisticated quantitative analytical techniques, butto provide a method for rapidly screening samples for radioactivity above ambient background levels or user-defined criteria, orboth, for facilities prohibited from handling radioactive waste.1.3 This test method may not
5、 be suitable for applications such as site assessments and remediation activities.1.4 The values stated in SI units are to be regarded as the standard.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of thi
6、s standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:2C859 Terminology Relating to Nuclear Materials3. Terminology3.1 For terminology related to radioactive materials, see Termi
7、nology C859.4. Summary of Test Method4.1 A sample is held within 6 mm of the detector window of a radiation survey meter, and the visible or audible reaction of themeter, or both, is noted. The user defines an application/project specific “negative” and “positive” result criteria. A “negative” testr
8、esult indicates radiation levels are below the user-established criteria; a “positive” test result indicates the radiation levels areabove the user-established criteria.5. Significance and Use5.1 Most facilities disposing or utilizing waste materials are prohibited from handling wastes that contain
9、radioactive materials.This test method provides the user a rapid method for screening waste material samples in the field or laboratory for the presenceor absence of radioactivity at user-established criteria. It is important to these facilities to be able to verify generator-suppliedinformation tha
10、t radioactive or mixed wastes have not been included in shipments of waste materials.6. Interferences6.1 Needle deflections or audible clicks of the survey meter, or both, occur due to naturally occurring omni-directionalbackground radiation. This level of ambient background radiation should be peri
11、odically assessed. See Section 10.1 This test method practice is under the jurisdiction of ASTM Committee D34 on Waste Management and is the direct responsibility of Subcommittee D34.01.05 onScreening Methods.Current edition approved Jan. 1, 2010Jan. 15, 2018. Published January 2010January 2018. Ori
12、ginally approved in 1996. Last previous edition approved in 20032010 asD5928 96D5928(2003). 96 (2010)1. DOI: 10.1520/D5928-96R10E01.10.1520/D5928-18.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standa
13、rdsvolume information, refer to the standards Document Summary page on the ASTM website.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible t
14、o 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 considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Con
15、shohocken, PA 19428-2959. United States16.2 Possible sources of interference include pacemakers, X-ray generating equipment, radium-based luminescent dials,polonium-based static eliminators, and smoke detectors containing a radioactive isotope sensing mechanism. Such interferencescan usually be trac
16、ed to their source using the portable instrument specified in this test method.6.3 Alarge amount of potassium in the waste sample may produce a positive result due to the natural presence of the radioactiveisotope, Potassium-40.6.4 The sensitivity of this test method to beta and gamma radiation may
17、be dependent on sample volume. A small samplevolume with readings near background levels may give a false negative result.6.5 Some radioactive isotopes, such as 3H and 14C, may not emit radiation of sufficient energy to be detected. If suspected tobe present in the waste, another procedure should be
18、 used that is appropriate to their determination.6.6 Liquid samples, as well as moisture in solid samples, are good attenuators of radiation and will hinder detection of manyradionuclides unless they emit high-energy gamma radiation. The possible inability to detect alpha particles and low-level bet
19、aemissions that may be attenuated, in many cases, should not be a serious shortcoming in this test method because these emissionsare often accompanied by higher energy gamma emissions.6.6.1 Moisture-laden Americium-241 bearing waste would be a case where there is a high probability of non-detection
20、due toattenuation.6.7 Survey meter contamination can cause artificially low or high results when reading standard sources or ambient background.If this occurs, the survey meter performance shall be considered unreliable and should be appropriately decontaminated byqualified personnel, or disposed of
21、 in accordance with applicable regulations.6.8 The radiation monitor should be operated in accordance with the manufacturers instructions.7. Apparatus7.1 Radiation Survey Meter, with a halogen-quenched uncompensated Geiger-Mueller tube with thin mica end-window. It isadvisable to choose an instrumen
22、t model that has an internal counter (cpm) or is capable of operating in a scaler mode.NOTE 1The meter used in the development of this test method was the Monitor 4.3Anumber of other survey meters4 are suitable for this test method.Through the end-window, this unit is capable of detecting and indica
23、ting alpha radiation (down to 2.5 MeV with a typical detection efficiency of 80 %at 3.6 MeV), beta radiation (down to 150 KeV with a typical 75 % detection efficiency), gamma radiation and X-rays (down to 10 KeV), with the surveymeter set on its lowest energy range of 0.1 Sv/h.8. Reagents and Materi
24、als8.1 The check sources used in the development of this test method were manufactured by Oxford Instruments, Inc.5 Othersuitable check sources are available from a number of suppliers.6 The check sources used in the development of this test methodare federally exempt and do not require licensing. S
25、ources other than the following (that is, Cesium 137) are appropriate for thistest method. The sources, levels of activity, and half-lives used in the development of this test method are as follows:Source Type Activity Half-Life (t12)Polonium 210 alpha 0.037 GBq138.4 daysStrontium 90 beta 0.037 GBq2
26、8.6yearsCobalt 60 gamma 3.7 G Bq 5.3years8.2 Check sources should be replaced at least every three half-lives.9. Sample9.1 Because stratification of liquid samples is possible, thoroughly mix the sample by shaking or stirring prior to testing.Strongly multiphasic samples should have each layer teste
27、d separately. Solid samples should be thoroughly mixed by a methodappropriate to their size and physical characteristics.10. Calibration and Standardization10.1 Check the battery power source of the survey meter prior to use. If the battery check indicates that the battery charge isnot in the optima
28、l power range, it must be replaced prior to use.10.2 Check the survey meters performance at least daily using the , , and check sources. This is done by observing thesurvey meter response when held within 6 mm of each check standard. At a minimum, check sources should be 2 times theambient backgroun
29、d. The check sources listed in 9.1 far exceed this requirement.3 Manufactured by SE International, Inc., Summertown, TN.4 For example, Five Level Portable Meter, manufactured by Harshaw-Bicron, Inc., Solon, OH; Ludlum Measurements, Inc., Sweetwater, TX; and Eberline InstrumentCorp., Santa Fe, NM.5 O
30、xford Instruments, Inc., Oak Ridge, TN.6 For example, The Source, Inc., Santa Fe, NM; Ludlum Measurements, Inc., Sweetwater, TX; and Eberline Instrument Corp., Santa Fe, NM.D5928 18210.3 The survey meter should be factory-calibrated at least yearly.10.4 Assess the level of ambient background radiati
31、on periodically. This may be prior to each test, daily, weekly, or monthlydepending on user requirements.10.4.1 Set the survey meter to its X1 or most sensitive setting and enable the audible alarm, if unit is so equipped.10.4.2 Record the number of audible meter clicks over a period of 60 s (counts
32、 per minute). Repeat this procedure two moretimes, and take the average of the three repetitions using the following formula:Average ambient background radiation5Measurement No. 11Measurement No. 21Measurement No. 3310.5 Unexpectedly high readings for ambient background or standard sources infers th
33、at the survey meter is contaminated. Seethe section on Interferences.10.6 The user must clearly define the criteria to be used for reporting “negative” or “positive” test results. These criteria maybe project- or application-specific. A common defining point used is “two to three times the ambient b
34、ackground level.”11. Procedure11.1 Perform the necessary steps presented in Section 10.11.2 Allow the survey meter to stabilize for 10 to 15 s at its X1 or lowest appropriate setting.11.3 Place the end-window of the survey meter within 6 mm of the sample. Depending on the physical characteristics of
35、 thesample container (for example, the container is such that the sample is 6 mm from the opening), it may be necessary to withdrawa representative portion of the sample to an alternate sample container, watch glass, or other appropriate vessel to allow theend-window to be placed within 6 mm of the
36、sample. Do not allow the survey meter to come in direct contact with the sample.This may contaminate the meter and may damage the end-window.11.4 Record the counts per minute for a period of 60 s (counts per minute).11.5 If the counts per minute are above the user-defined criteria, then the sample m
37、ay contain radioactive material.NOTE 2The user should recognize the potential interferences mentioned in Section 6.11.6 If radioactivity levels above the user-defined criteria are observed, the background levels should be redetermined asdescribed in Section 10. The sample should then be retested beg
38、inning with 11.2.11.7 If radioactivity levels are confirmed to be above the user-defined criteria, sample testing should be discontinued, and theappropriate health and safety professional or site regulatory officer should be contacted for further instructions.11.8 If radioactivity levels are below t
39、he user-defined criteria, the test result may be recorded as not detected.12. Precision and Bias12.1 PrecisionNo statement is made about the precision because this screening test method produces only a positive ornegative test result.12.2 BiasNo statement is made about the bias because this screenin
40、g test method produces only a positive or negative testresult.13. Keywords13.1 radioactivity; screening method; waste materialsASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are
41、expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not re
42、vised, either reapproved or withdrawn.Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you m
43、ay attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United St
44、ates. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also b
45、e secured from the Copyright Clearance Center, 222Rosewood Drive, Danvers, MA 01923, Tel: (978) 646-2600; http:/ Scope1.1 This practice covers the screening for , , and radiation above ambient background levels or user-defined criteria, orboth, in liquid, sludge, or solid waste materials.D5928 1831.
46、2 This practice is intended to be a gross screening method for determining the presence or absence of radioactive materialsin liquid, sludge, or solid waste materials. It is not intended to replace more sophisticated quantitative analytical techniques, butto provide a method for rapidly screening sa
47、mples for radioactivity above ambient background levels or user-defined criteria, orboth, for facilities prohibited from handling radioactive waste.1.3 This practice may not be suitable for applications such as site assessments and remediation activities.1.4 The values stated in SI units are to be r
48、egarded as the standard.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability ofregulatory li
49、mitations prior to use.1.6 This international standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2C859 Terminology Relating to Nuclear Materials3. Terminology3.1 For terminology related to radioactive materials, see Terminology C859.4. Summary o
