1、Designation: E2033 99 (Reapproved 2013)Standard Practice forComputed Radiology (Photostimulable LuminescenceMethod)1This standard is issued under the fixed designation E2033; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year
2、 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 practice2covers application details for computedradiology (CR) examination using a process in which photo-sti
3、mulable luminescence is emitted by the penetrating radiationdetector, a storage phosphor imaging plate (SPIP). Because thetechniques involved and the applications for CR examinationare diverse, this practice is not intended to be limiting orrestrictive, but rather to address the general applications
4、 of thetechnology and thereby facilitate its use. Refer to Guides E94and E2007, Terminology E1316, and Practices E747 andE1025, and 21 CFR 1020.40 and 29 CFR 1910.96 for addi-tional information and guidance.1.2 The general principles discussed in this practice applybroadly to penetrating radiation C
5、R systems. However, thisdocument is written specifically for use with X-ray andgamma-ray systems. Other CR systems, such as those employ-ing neutrons, will involve equipment and application detailsunique to such systems.1.3 This standard does not purport to address all of thesafety concerns, if any,
6、 associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use. For specific safetystatements, see Section 10 and 21 CFR 1020.40 and 29 CFR1910.96.2. Referenc
7、ed Documents2.1 ASTM Standards:3E94 Guide for Radiographic ExaminationE747 Practice for Design, Manufacture and Material Group-ing Classification of Wire Image Quality Indicators (IQI)Used for RadiologyE1025 Practice for Design, Manufacture, and MaterialGrouping Classification of Hole-Type Image Qua
8、lity In-dicators (IQI) Used for RadiologyE1316 Terminology for Nondestructive ExaminationsE1453 Guide for Storage of Magnetic Tape Media thatContains Analog or Digital Radioscopic DataE1475 Guide for Data Fields for Computerized Transfer ofDigital Radiological Examination DataE1817 Practice for Cont
9、rolling Quality of Radiological Ex-amination by Using Representative Quality Indicators(RQIs)E2007 Guide for Computed Radiography2.2 ASNT Standards:SNT-TC-1A Recommended Practice for Personnel Qualifi-cation and Certification in Nondestructive Testing4ANSI/ASNT-CP-189 Standard for Qualification and
10、Certifi-cation of Nondestructive Testing Personnel42.3 Federal Standards:Title 21, CFR 1020.40 Safety Requirements of CabinetX-Ray Systems5Title 29, CFR 1910.96 Ionizing Radiation52.4 AIA Standard:NAS-410 Certification and Qualification of NondestructiveTesting Personnel63. Summary of Practice3.1 AC
11、R examination system can be used for a wide varietyof applications. A typical CR examination system consists of aradiation source, a storage phosphor imaging plate detector, aplate reader, an electronic imaging system, a digital imageprocessor, a monitor display, a digital image archiving system,and
12、, if desired, equipment for producing hard copy analogimages. This practice establishes the basic parameters for theapplication and control of the CR method.1This test method is under the jurisdiction of ASTM Committee E07 onNondestructive Testing and is the direct responsibility of Subcommittee E07
13、.01 onRadiology (X and Gamma) Method.Current edition approved June 1, 2013. Published June 2013. Originallyapproved in 1999. Last previous edition approved in 2006 as E2033 - 99 (2006).DOI: 10.1520/E2033-99R13.2ForASME Boiler and Pressure Code applications, see related Practice SE-2033in Section II
14、of that code.3For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.4Available from American Society for Nondestruct
15、ive Testing, 1711 ArlingatePlaza, P.O. Box 28518, Columbus, OH 43228-0518.5Available from Standardization Documents Order Desk, Bldg. 4 Section D, 700Robbins Ave., Philadelphia, PA 19111-5094, Attn: NPODS.6Available fromAerospace IndustriesAssociation ofAmerica, Inc., 1250 Eye St.NW, Washington, D.C
16、. 20005.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States14. Significance and Use4.1 The X-, gamma-ray detector discussed in this practice isa storage phosphor imaging plate, hereafter referred to as SPIP.The SPIP, which is the key comp
17、onent in the CR process,differentiates CR from other radiologic methods. This practiceis written so that it can be specified on the engineeringdrawing, specification, or contract and must be supplementedby a detailed procedure (see Section 6 and Annex A1 andAnnex A2).5. Equipment5.1 System Configura
18、tionDifferent examination systemsconfigurations are possible, and it is important to understandthe advantages and limitations of each. It is important that theoptimum system be selected for each examination requirementthrough a careful analysis of the benefits and limitations of theavailable system
19、components and the chosen system configu-ration. The provider as well as the user of the examinationservices should be fully aware of the capabilities and limita-tions of the examination system that is proposed for examina-tion of the part. The provider and the user of examinationservices shall agre
20、e upon the system configuration to be usedfor each application under consideration and how its perfor-mance is to be evaluated.5.1.1 The minimum system configuration will include anappropriate source of penetrating radiation, a phosphor platedetector, a plate reader, and an electronic imaging system
21、 witha CRT display.5.1.2 A more complex system might include a microfocusX-ray system, a digital image processing evaluation system,and an image recording and printing system.6. General Procedure Considerations6.1 The purchaser and supplier shall mutually agree upon awritten procedure using the appl
22、icable annex of supplementalrequirements and also consider the following general require-ments.6.1.1 Equipment QualificationsA listing of the systemfeatures that must be qualified to ensure that the system iscapable of performing the desired examination.6.1.2 Source ParameterA listing of all the rad
23、iationsource-related variables that can affect the examination resultsfor the selected system configuration such as: source energy,intensity, focal spot size, range of source to object distances,range of object to image plane distances, and source to imageplane distances.6.1.3 Image Processing Param
24、etersA listing of the imageprocessing variables, if any, necessary to enhance fine detaildetectability in the part and to achieve the required imagequality. These would include, but are not limited to, techniquessuch as noise reduction, contrast enhancement, and spatialfiltering. Great care should b
25、e exercised in the selection ofdirectional image processing parameters such as spatialfiltering, which may emphasize features in certain orientationsand suppress them in others. The listing should indicate themeans for qualifying image processing parameters.6.1.4 Image Display ParametersA listing of
26、 the tech-niques and the intervals at which they are to be applied forstandardizing the video image display as to brightness,contrast, focus, and linearity.6.1.5 Accept-Reject CriteriaA listing of the expectedkinds of part imperfections and the rejection level for each.6.1.6 Performance EvaluationA
27、listing of the qualifica-tion tests and the intervals at which they are to be applied toensure the system is suitable for its intended purpose.6.1.7 Image Archiving RequirementsA listing of therequirements, if any, for preserving a historical record of theexamination results. The listing may include
28、 examinationimages along with written or electronically recorded alphanu-meric or audio narrative information, or both, sufficient toallow subsequent reevaluation or repetition of the examination.6.1.8 QualificationsNondestructive testing (NDT) person-nel shall be qualified in accordance with a nati
29、onally recog-nized NDT personnel qualification practice or a standard suchas ANSI/ASNT-CP-189, SNT-TC-1A, NAS-410, or a similardocument.7. CR Examination System Performance Considerationsand Measurement7.1 Factors Affecting System PerformanceTotal examina-tion system performance is determined by the
30、 combinedperformance of the system components that includes theradiation source, storage phosphor plate detector, plate reader,electronic image processing system, image display, and exami-nation record archiving system.7.1.1 Radiation SourcesExamination systems may utilizeeither radioisotope or X-ra
31、y sources. The energy spectrum ofthe X-radiation contains a blend of contrast enhancing longerwavelengths as well as the more penetrating, shorter wave-lengths. X-radiation is adjustable in energy and intensity tomeet the CR examination requirements and has the addedsafety feature of discontinued ra
32、diation production whenswitched off.Aradioisotope source has the advantages of smallphysical size, portability, simplicity, and uniformity of output.7.1.1.1 X-ray machines produce a more intense X-ray beamemanating from a smaller focal spot than do radioisotopesources. X-ray focal spot sizes range f
33、rom a few millimetersdown to a few micrometers. Reducing the source size reducesgeometric unsharpness, thereby enhancing detail sensitivity.X-ray sources may offer multiple or variable focal spot sizes.Smaller focal spots produce higher resolution with reducedX-ray beam intensity, while larger focal
34、 spots can providehigher X-ray intensity with lower resolution. Microfocus X-raytubes are available with focal spots that may be adjusted to assmall as a few micrometers in diameter while still producing anX-ray beam of sufficient intensity so as to be useful for the CRexamination of finely detailed
35、 parts.7.1.1.2 Conventional focal spots of 1.0 mm and larger areuseful at low geometric magnification values close to 1.Fractional focal spots ranging from 0.4 mm up to 1.0 mm areuseful at geometric magnifications up to approximately 2.Minifocus spots in the range from 0.1 mm up to 0.4 mm areuseful
36、at geometric magnifications up to about 6. Greatermagnifications suggest the use of a microfocus spot size of lessthan 0.1 mm to minimize the effects of geometric unsharpness.Microfocus X-ray tubes are capable of focal spot sizes of lessE2033 99 (2013)2than 10 m (108m) and are useful for geometric m
37、agnifica-tions of more than 100.7.1.2 SPIPThe storage phosphor imaging plate is a keyelement. It has the function of converting the radiation inputsignal containing part information into a corresponding opticalsignal while preserving the maximum amount of part informa-tion. The SPIP is a two-dimensi
38、onal area detector providing anarea field of view.7.1.3 SPIP ReaderThe SPIP reader has the function ofoptically scanning the imaging plate, collecting the emittedlight, converting the light to an electronic signal, then convert-ing this signal to a digital format.7.1.4 Electronic Imaging Processing
39、System:7.1.4.1 The function of the electronic imaging processingsystem is to take the output of the SPIP reader and present adigital file for image display and operator interpretation.7.1.4.2 The electronic imaging processing system includesall of the electronics and interfaces after the SPIP reader
40、,including image enhancement and image display.7.1.4.3 The digital image processing system warrants spe-cial attention because it is the means by which examinationinformation will be interpreted. Great care must be exercised indetermining which image processing techniques are mostbeneficial for the
41、particular application. Directional spatialfiltering operations, for example, must be given special atten-tion as certain feature orientations are emphasized while othersare suppressed.7.1.5 Image Display:7.1.5.1 The function of the image display is to conveyinformation about the part to the system
42、operator. The imagedisplay size, spatial resolution, magnification, and ambientlighting are important system considerations.7.1.6 Examination Record Archiving SystemMany appli-cations require an archival quality examination record of theexamination. The archiving system may take many forms, afew of
43、which are listed in 7.1.6.1 through 7.1.6.5. Eacharchiving system has its own peculiarities as to image quality,archival storage properties, equipment, and media cost. Theexamination record archiving system should be chosen on thebasis of these and other pertinent parameters, as agreed uponby the pr
44、ovider and user of services. The reproduction qualityof the archival method should be sufficient to demonstrate thesame image quality as was used to qualify the examinationsystem.7.1.6.1 Film or paper radiographs of the part made under thesame conditions as the examination image.7.1.6.2 Photograph o
45、f the actual image display.7.1.6.3 CRT hard copy device used to create a paper copyimage from the CRT signal.7.1.6.4 Digital recording on magnetic disk or tape used tostore the image of the part digitally.7.1.6.5 Digital recording on optical disk used to store theimage of the part digitally.7.1.7 Ex
46、amination Record DataThe examination recordshould contain sufficient information to allow the examinationto be reevaluated or duplicated. Examination record datashould be recorded contemporaneously with the CR examina-tion image. Examination record data should be in accordancewith Guide E1475 and ma
47、y be in writing or a voice narrative,providing the following minimum data:7.1.7.1 Examination system designation, examination date,operator identification, operating turn or shift, and otherpertinent and customer data;7.1.7.2 Specific examination data as to part number, batch,serial number, and so f
48、orth (as applicable);7.1.7.3 Part orientation and examination site information byreference to unique part features within the field of view; and7.1.7.4 System performance monitoring by recording theresults of the prescribed examination system performancemonitoring tests, as set forth in Section 5, a
49、t the beginning andend of a series of examinations.7.2 Performance MeasurementSystem performance pa-rameters must be determined initially and monitored regularlyto ensure consistent results. The best measure of total CRexamination system performance can be made with the systemin operation, utilizing a representative quality indicator (RQI)similar to the part under actual operating conditions. Thisindicates the use of an actual or simulated part containingactual or simulated features that must be reliably detected.Such an RQI will provide a reliable indication of
