ASTM E2698-18e1

Standard Practice for Radiographic Examination Using Digital Detector Arrays

SIGNIFICANCE AND USE
4.1 This practice establishes the basic parameters for the application and control of the digital detector array radiographic method. This practice is written so it can be specified on the engineering drawing, specification, or contract. It will require a detailed procedure delineating the technique or procedure requirements and shall be approved by the Cognizant Engineering Organization (CEO).
SCOPE
1.1 This practice establishes the minimum requirements for radiographic examination of metallic and nonmetallic materials using digital detector arrays (DDAs).  
1.2 The stated requirements of this specification are based on the use of an X-ray generating source. Additionally, some of the tests and requirements may not be applicable to X-ray energy levels >450kV.  
1.3 The requirements in this practice are intended to control the quality of radiographic examinations obtained using DDAs and are not intended to establish acceptance criteria for parts or materials.  
1.4 This practice covers the radiographic examination with DDAs including DDAs described in Practice E2597/E2597M such as a device that contains a photoconductor attached to a Thin Film Transistor (TFT) read out structure, a device that has a phosphor coupled directly to an amorphous silicon read-out structure, and devices where a phosphor is coupled to a CMOS (complementary metal–oxide–semiconductor) array, or a CCD (charge coupled device) crystalline silicon read-out structure.  
1.5 The requirements of this practice and Practice E2737 shall be used together. The requirements of Practice E2737 will provide the baseline evaluation and long term stability test procedures for the DDA system. The user of the DDA system shall establish a written procedure that addresses the specific requirements and tests to be used in their application and shall be approved by the Cognizant Radiographic Level 3 before examination of production hardware. This practice also requires the user to perform a system qualification suitable for its intended purpose and to issue a system qualification report (see 9.1).  
1.6 The DDA shall be selected for an NDT application based on knowledge of the technology described in Guide E2736, and of the selected DDA properties provided by the manufacturer in accordance with Practice E2597/E2597M.  
1.7 Techniques and applications employed with DDAs are diverse. This practice is not intended to be limiting or restrictive. Refer to Guides E94/E94M, E1000, and E2736, Terminology E1316, Practices E747 and E1025, and Federal Standards 21-CFR-1020.40 and 29-CFR-1910.96 for a list of documents that provide additional information and guidance.  
1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

General Information

• Status: Published
• Publication Date: 31-Jan-2018
• ICS: 11.040.50 - Radiographic equipment
• Technical Committee: E07 - Nondestructive Testing
• Drafting Committee: E07.01 - Radiography (X and Gamma) Method

Relations

• Refers: ASTM E1316-24 - Standard Terminology for <?Pub Dtl?>Nondestructive Examinations
• Effective Date: 01-Feb-2024
• Refers: ASTM E1742/E1742M-23 - Standard Practice for Radiographic Examination
• Effective Date: 15-Dec-2023
• Refers: ASTM E1316-19b - Standard Terminology for Nondestructive Examinations
• Effective Date: 01-Dec-2019
• Refers: ASTM E1316-19 - Standard Terminology for Nondestructive Examinations
• Effective Date: 01-Mar-2019
• Refers: ASTM E2699-18 - Standard Practice for Digital Imaging and Communication in Nondestructive Evaluation (DICONDE) for Digital Radiographic (DR) Test Methods
• Effective Date: 01-Nov-2018
• Refers: ASTM E1742/E1742M-18 - Standard Practice for Radiographic Examination
• Effective Date: 01-Mar-2018
• Refers: ASTM E1025-18 - Standard Practice for Design, Manufacture, and Material Grouping Classification of Hole-Type Image Quality Indicators (IQI) Used for Radiography
• Effective Date: 01-Feb-2018
• Refers: ASTM E2903-18 - Standard Test Method for Measurement of the Effective Focal Spot Size of Mini and Micro Focus X-ray Tubes
• Effective Date: 01-Feb-2018
• Refers: ASTM E1316-18 - Standard Terminology for Nondestructive Examinations
• Effective Date: 01-Jan-2018
• Refers: ASTM E1316-17a - Standard Terminology for Nondestructive Examinations
• Effective Date: 15-Jun-2017
• Refers: ASTM E1316-17 - Standard Terminology for Nondestructive Examinations
• Effective Date: 01-Feb-2017
• Refers: ASTM E1000-16 - Standard Guide for Radioscopy
• Effective Date: 01-Dec-2016
• Refers: ASTM E1316-16a - Standard Terminology for Nondestructive Examinations
• Effective Date: 01-Aug-2016
• Refers: ASTM E1316-16 - Standard Terminology for Nondestructive Examinations
• Effective Date: 01-Feb-2016
• Refers: ASTM E1316-15a - Standard Terminology for Nondestructive Examinations
• Effective Date: 01-Dec-2015

Overview

ASTM E2698-18e1, Standard Practice for Radiographic Examination Using Digital Detector Arrays, published by ASTM, provides comprehensive procedures for conducting radiographic examination of metallic and nonmetallic materials using digital detector arrays (DDAs). This standard establishes the minimum requirements to ensure consistent quality in the application and control of digital radiography. The guidance is designed to be referenced directly in engineering drawings, specifications, or contracts, and it requires the development of detailed, application-specific procedures subject to approval by the Cognizant Engineering Organization (CEO).

The practice complements and should be used in conjunction with ASTM E2737, which covers DDA system performance and long-term stability. It applies primarily to X-ray sources with energy levels up to 450kV and outlines the responsibilities for personnel qualification, equipment control, and procedural documentation.

Key Topics

• Scope of Application: Covers radiographic examination using DDAs for both metallic and nonmetallic materials, with a focus on industrial non-destructive testing (NDT).
• System Requirements: Identifies technical and procedural requirements for DDAs, including types such as TFT, CMOS, CCD, and amorphous silicon devices.
• Procedure Development: Requires the creation of written, detailed procedures approved by a qualified Level 3 Radiographer. Procedures must address technique, system qualification, quality assurance, and documentation.
• Quality Control: Stipulates requirements for system qualification, routine monitoring, and long-term stability in accordance with recognized practices (e.g., ASTM E2737).
• Personnel Qualification: Specifies that personnel must be qualified under recognized certification standards such as NAS410, EN 4179, ANSI/ASNT CP 189, ISO 9712, or SNT-TC-1A, with documented certification.
• Image Display and Interpretation: Details criteria for display monitors, including brightness, contrast, the ability to resolve fine details, and avoidance of artifacts, ensuring accurate image evaluation.
• Image Quality Indicators (IQIs): Provides guidance for the use, selection, and placement of IQIs to verify radiographic sensitivity and image quality for specific applications.
• Documentation and Traceability: Emphasizes thorough documentation of procedural and examination data, including system qualification records, image identification, and environmental conditions.

Applications

ASTM E2698-18e1 is widely used in sectors requiring high-reliability non-destructive testing (NDT), notably:

• Aerospace: Inspection of critical components like castings, forgings, and weldments, where precise detection of discontinuities is essential.
• Automotive: Evaluation of parts and assemblies where structural integrity must be verified non-invasively.
• Power Generation: Examination of pressure vessels, turbine components, and other safety-critical infrastructure.
• Manufacturing: Quality control and verification of products where internal features or flaws need to be assessed without damaging the item.
• Research and Development: Where new materials or assemblies demand state-of-the-art, high-resolution radiographic evaluation.

Digital radiographic examination using DDAs increases workflow efficiency, enhances image quality, and facilitates digital archiving and traceability compared to traditional film methods.

Related Standards

For efficient and compliant implementation of ASTM E2698-18e1, several related standards should be considered in conjunction:

• ASTM E2597/E2597M: Manufacturing characterization of DDAs.
• ASTM E2737: DDA performance evaluation and long-term stability testing.
• ASTM E2736: Guide for digital detector array radiography technology.
• ASTM E1025, E747, E1742/E1742M: Design and application of image quality indicators (IQIs).
• ASTM E94/E94M, E1000: General radiographic examination practices.
• ASTM E2339, E2699: Digital imaging and communications in NDT.
• Personnel Qualification: NAS410, EN 4179, ISO 9712, ANSI/ASNT CP 189, SNT-TC-1A.
• Safety Requirements: 21-CFR-1020.40, 29-CFR-1910.96, NCRP 144, NIST Handbook 114.

Consulting these related standards ensures alignment with international best practices in the use of digital radiographic examination for non-destructive testing.

Keywords: ASTM E2698-18e1, digital detector arrays, radiographic examination, NDT, non-destructive testing, image quality indicators, system qualification, industrial radiography, DDA, ASTM standards, procedural requirements, quality control, personnel certification.

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
ϵ1
Designation: E2698 − 18
Standard Practice for
Radiographic Examination Using Digital Detector Arrays
This standard is issued under the fixed designation E2698; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
ε NOTE—10.15.3.2 was revised editorially in September 2018 to remove a duplicate paragraph.
1. Scope E2736, and of the selected DDA properties provided by the
manufacturer in accordance with Practice E2597/E2597M.
1.1 This practice establishes the minimum requirements for
radiographicexaminationofmetallicandnonmetallicmaterials 1.7 Techniques and applications employed with DDAs are
diverse. This practice is not intended to be limiting or restric-
using digital detector arrays (DDAs).
tive. Refer to Guides E94/E94M, E1000, and E2736, Termi-
1.2 The stated requirements of this specification are based
nology E1316, Practices E747 and E1025, and Federal Stan-
ontheuseofanX-raygeneratingsource.Additionally,someof
dards 21-CFR-1020.40 and 29-CFR-1910.96 for a list of
the tests and requirements may not be applicable to X-ray
documents that provide additional information and guidance.
energy levels >450kV.
1.8 This international standard was developed in accor-
1.3 The requirements in this practice are intended to control
dance with internationally recognized principles on standard-
the quality of radiographic examinations obtained using DDAs
ization established in the Decision on Principles for the
andarenotintendedtoestablishacceptancecriteriaforpartsor
Development of International Standards, Guides and Recom-
materials.
mendations issued by the World Trade Organization Technical
1.4 This practice covers the radiographic examination with
Barriers to Trade (TBT) Committee.
DDAs including DDAs described in Practice E2597/E2597M
such as a device that contains a photoconductor attached to a
2. Referenced Documents
ThinFilmTransistor(TFT)readoutstructure,adevicethathas 2
2.1 ASTM Standards:
a phosphor coupled directly to an amorphous silicon read-out
E94/E94M Guide for Radiographic Examination Using In-
structure, and devices where a phosphor is coupled to a CMOS
dustrial Radiographic Film
(complementary metal–oxide–semiconductor) array, or a CCD
E543 Specification forAgencies Performing Nondestructive
(charge coupled device) crystalline silicon read-out structure.
Testing
1.5 The requirements of this practice and Practice E2737
E747 Practice for Design, Manufacture and Material Group-
shallbeusedtogether.TherequirementsofPracticeE2737will ing Classification of Wire Image Quality Indicators (IQI)
provide the baseline evaluation and long term stability test
Used for Radiology
procedures for the DDA system. The user of the DDA system E1000 Guide for Radioscopy
shall establish a written procedure that addresses the specific
E1025 Practice for Design, Manufacture, and Material
requirements and tests to be used in their application and shall Grouping Classification of Hole-Type Image Quality In-
be approved by the Cognizant Radiographic Level 3 before
dicators (IQI) Used for Radiography
examination of production hardware. This practice also re- E1165 Test Method for Measurement of Focal Spots of
quires the user to perform a system qualification suitable for its
Industrial X-Ray Tubes by Pinhole Imaging
intendedpurposeandtoissueasystemqualificationreport(see E1316 Terminology for Nondestructive Examinations
9.1).
E1742/E1742M Practice for Radiographic Examination
E1817 Practice for Controlling Quality of Radiological Ex-
1.6 The DDA shall be selected for an NDT application
amination by Using Representative Quality Indicators
based on knowledge of the technology described in Guide
(RQIs)
E2002 Practice for Determining Total Image Unsharpness
This practice is under the jurisdiction of ASTM Committee E07 on Nonde-
structive Testing and is the direct responsibility of Subcommittee E07.01 on
Radiology (X and Gamma) Method. For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Current edition approved Feb. 1, 2018. Published April 2018. Originally contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
approved in 2010. Last previous edition approved in 2010 as E2698 – 10. DOI: Standards volume information, refer to the standard’s Document Summary page on
10.1520/E2698-18E01. the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
ϵ1
E2698 − 18
and Basic Spatial Resolution in Radiography and Radios- 3.2.1 bad pixel—a pixel identified with a performance
copy outside of the specification range for a pixel of a DDA as
E2339 Practice for Digital Imaging and Communication in defined in Practice E2597/E2597M.
Nondestructive Evaluation (DICONDE) detector
3.2.2 basic spatial resolution detector (iSR )—the
b
E2597/E2597M PracticeforManufacturingCharacterization
smallest geometrical detail, which can be resolved by a digital
of Digital Detector Arrays
detectorwithoutgeometricmagnificationasdefinedinPractice
E2699 Practice for Digital Imaging and Communication in
E2597/E2597M.
Nondestructive Evaluation (DICONDE) for Digital Ra-
3.2.3 cluster kernel pixel (CKP)—a bad pixel, as defined in
diographic (DR) Test Methods
Practice E2597/E2597M, that does not have five or more good
E2736 Guide for Digital Detector Array Radiography
pixels as neighbors and is therefore not correctable.
E2737 Practice for Digital Detector Array Performance
Evaluation and Long-Term Stability
3.2.4 Cognizant Radiographic Level 3—the certified Level
E2903 Test Method for Measurement of the Effective Focal
3 Radiographer holding final technical responsibility for the
Spot Size of Mini and Micro Focus X-ray Tubes
radiographic facility and staff.
2.2 AWS Documents:
3.2.5 compensation principle—the practice of permitting an
AWSA2.4 Symbols forWelding and NondestructiveTesting
examination scenario where the total image unsharpness fails
2.3 Government Standards:
to meet the required value, but the image quality exceeds the
NIST Handbook 114 General Safety Standard for Installa-
required value by at least one quality level. See Guide E2736
tions Using Non-Medical X-ray and Sealed Gamma Ray
4 for additional information regarding this term.
Sources, Energies up to 10 MeV
21-CFR-1020.40 Safety Requirements of Cabinet X-ray
3.2.6 component—the part(s) or element of a system as-
Systems sembled or processed to the extent specified by the drawing,
29-CFR-1910.96 Ionizing Radiation
purchase order, or contract.
NCRP 144 Radiation Protection for Particle Accelerator
3.2.7 contrast-to-noise ratio (CNR)—quotient of the dif-
Facilities
ference in the mean values of the intensity (signal) in an area
2.4 Other Documents:
in the object subtracted from the mean value of the intensity of
DICOM PS 3.14 Digital Imaging and Communications in
thebackground,andstandarddeviationoftheintensity(noise).
Medicine (Dicom) Part 14: Grayscale Standard Display
The CNR depends on the radiation dose and quality, thickness/
Function
attenuation of the object and the DDA system properties.
ANSI/NCSL Z540-3 Requirements for the Calibration of
3.2.8 digital driving level (DDL)—for computer graphics
Measuring and Test Equipment
displayboards,thedigitalvaluethatcorrespondstoaparticular
ANSI/ASNT CP 189 Standard for Qualification and Certifi-
monochromegrayscalelevel.AparticularDDL“drivesout”
cation of Nondestructive Testing Personnel
a particular visible shade of gray. For example, in an 8-bit
EN 4179 Aerospace Series - Qualification and Approval of
display, a DDL assumes 256 values from 0 to 255.
Personnel for Non-destructive Testing
NAS 410 National Aerospace Standard Certification and
3.2.9 effective pixel size—Effective pixel size is equal to
detector
Qualification of Nondestructive Testing Personnel
iSR .
b
SNT-TC-1A Recommended Practice - Personnel Qualifica-
3.2.10 energy—a property of radiation that determines the
tion and Certification in Nondestructive Testing
penetratingability.Inx-rayradiography,energymachinerating
ISO 9712 Non-destructive Testing - Qualification and Cer-
is determined by kilo electron volts (keV), million electron
tification of NDT personnel
volts (MeV). In gamma ray radiography, energy is a charac-
ISO/CIE 19476 Characterization of the Performance of Illu-
teristic of the source used.
minance Meters and Luminance Meters
SMPTE RP 133 Specifications for Medical Diagnostic Im-
3.2.11 ghosting—residual signal or image from a prior
aging Test Pattern for Television Monitors and Hard-copy
exposure in a current image. Signal or image can be negative
Recording Cameras
or positive and may affect interpretation of the image.
N
3.2.12 grayscale—2 signal levels for N-bit system.
3. Terminology
3.2.13 like section—a separate section of material that is
3.1 Definitions relating to the radiographic examination,
similar in shape and cross section to the component or part
which appear in Terminology E1316, shall apply to the terms
being radiographically examined, and is made of the same or
used in this practice.
radiographically similar material.
3.2 Definitions of Terms Specific to This Standard:
3.2.14 material group—materials that have the same pre-
dominant alloying elements and which can be examined using
Available from American Welding Society (AWS), 550 NW LeJeune Rd.,
the same IQI.Alisting of common material groups is given in
Miami, FL 33126, http://www.aws.org.
Practice E1025.
Available from National Institute of Standards and Technology (NIST), 100
Bureau Dr., Stop 1070, Gaithersburg, MD 20899-1070, http://www.nist.gov.
3.2.15 mean gray level—the average of all the pixel gray
Available fromAerospace IndustriesAssociation ofAmerica, Inc. (AIA), 1000
WilsonBlvd.,Suite1700,Arlington,VA22209-3928,http://www.aia-aerospace.org. levels in a given region of interest.
ϵ1
E2698 − 18
3.2.16 NDT facility—the facility or entity performing the system should be fully aware of the capabilities and limitations
radiographic examination. of each system proposed.
N
3.2.17 pixel value—one of 2 signal levels for an N-bit
7.2 The DDA cannot be operated without computing hard-
digital system
ware and software for image acquisition, image display and
image storage/retrieval.
3.2.18 relevant cluster—a grouping of bad pixels with at
7.2.1 The software shall be capable of acquiring images
least one cluster kernel pixel (CKP) in the grouping.
framebyframefromtheDDAandintegrating,oraveragingthe
3.2.19 window width and level—contrast (window width)
frames, or both.
andbrightness(windowlevel)adjustmentofadigitalimageby
7.2.2 The software shall perform an image calibration to
changing how the Gray levels translate into displayed bright-
correcttheinhomogenitiesofthedetectorandtodetermineand
ness levels.
correct bad pixels (that is, bad pixel map). Bad pixels are
defined in Practice E2597/E2597M.
4. Significance and Use
7.2.3 ThesoftwaretodisplayresultingimageryfromaDDA
4.1 This practice establishes the basic parameters for the
shall have the following capabilities at a minimum:
application and control of the digital detector array radio-
7.2.3.1 Line Profile—A line profile function capable of
graphic method. This practice is written so it can be specified
displaying the pixel values (PVs) along a user defined line as
on the engineering drawing, specification, or contract. It will
a graph. The line profile tool should also be capable of
require a detailed procedure delineating the technique or
adjusting the line width where the values of the line profile are
procedure requirements and shall be approved by the Cogni-
averaged from multiple parallel lines of equivalent length.
zant Engineering Organization (CEO).
7.2.3.2 Region of Interest Tool—A histogram type tool
capable of displaying the PVs of a user defined Region of
5. Basis of Application
Interest (ROI) as a graph. The ROI tool shall also display the
5.1 The following items are subject to contractual agree-
size of the ROI (in other words, x pixels by y pixels), and as a
ment between the parties using or referencing this standard.
minimum, the statistical mean and standard deviation of the
5.1.1 Personnel Qualification—Personnel performing ex-
ROI PVs.
aminationstothispracticeshallbequalifiedinaccordancewith
7.2.3.3 Negative/Positive Image Display—Display images
NAS410, EN 4179, ANSI/ASNT CP 189, ISO 9712, or
in either negative or positive gray scale (negative or inverse).
SNT-TC-1Aand certified by the employer or certifying agency
7.2.3.4 Linearized Pixel Values—The software shall be ca-
asapplicable.Otherequivalentqualificationdocumentsmaybe
pable of performing calculations using linearized pixel values
used when specified on the contract or purchase order. The
as a function of dose.
applicablerevisionshallbethelatestunlessotherwisespecified
7.2.3.5 Digital Image Magnification (Zoom)—Adjust and
in the contractual agreement between parties.
display the digital magnification level, as well as display the
5.1.2 If specified in the contractual agreement, NDT agen-
image at 1:1 pixel mapping (in other words, each pixel of the
cies shall be qualified and evaluated as described in Specifi-
image is mapped to an image display monitor pixel).
cationE543.TheapplicableeditionofSpecificationE543shall
7.2.3.6 Image Pan—Capability to pan the image.
be specified in the contract.
7.2.3.7 Window Width and Window Level (Window/Level)—
Adjust window width (contrast) and window level.
6. Environment and Safety
7.2.3.8 Size Measurement Tool—Perform measurements for
6.1 The premises and equipment shall present no hazards to
distance or sizing of discontinuities. The software shall be
the safety of personnel or property. NCRP 144, and/or NIST
capable of calibrating the measuring tool to a reference
Handbook 114 may be used as guides to ensure that radio-
standard.
graphic procedures are performed so that personnel shall not
7.2.3.9 Atool or tools capable of performing area measure-
receive a radiation dosage exceeding the maximum permitted
ments.
by the city, state, or national codes.
7.2.3.10 Image Format—Lossy compression shall not be
6.2 Environmental conditions conducive to human comfort
allowed for images that are used for final product disposition.
and concentration will promote examination efficiency and
For systems that are not DICONDE compliant, TIFF images
reliability. A proper examination environment will take into
are recommended.
account temperature, humidity, dust, lighting, access, and
7.2.3.11 The software shall be capable of saving a copy of
noise.
the radiographic image with image processing applied.
7.2.3.12 For systems that are DICONDE compliant the
6.3 Dust and dirt need to be kept to a minimum and the
software shall be capable of storing images in accordance with
image display face needs to be cleaned often to prevent
Practices E2339 and E2699.
interference with interpretation.
7.3 For systems used in the examination of castings, as well
7. Equipment
as other examinations where reference radiographs are used,
7.1 Different examination system configurations are pos- the software shall have the ability to direct the viewing
sible. It is important that the user understands the advantages properties of the production image and a reference radiograph
and limitations of each (see Practice E2597/E2597M and image in accordance with the applicableASTM or other digital
Guide E2736). The provider and the user of the examination reference radiograph standard or specification.
ϵ1
E2698 − 18
7.4 The Digital Detector Array (DDA): material group is not available, a material that is radiographi-
7.4.1 Only DDAs shall be used in practice as established in cally less dense shall be used.
Guide E2736.
7.6.3 Representative quality indicators (RQIs) may be used
7.4.2 Users shall comply with the manufacturers’ require- if approved by the Cognizant Engineering Organization. RQIs
ments of temperatures and humidity conditions for both
shall be in accordance with the requirements of Practice
operation and shipping. E1817.
7.4.3 The DDAshall be calibrated using the manufacturers’
7.6.4 The IQIs shall be procured or fabricated to the
recommendation both for frequency of calibration and the
requirements of Practice E1025, Practice E1742/E1742M (An-
method used. Other calibration methods are allowed as long as
nex 1), or Practice E747 with a manufacturer’s certification of
approved by the CEO.
compliance with respect to alloy and dimensions. Users shall
7.4.4 The user shall ensure that all exposures are within the
visually inspect IQIs for damage and cleanliness in accordance
linear operating range of the DDA, using either information
with Appendix X1.
obtained from the manufacturer or data obtained by the
7.7 Radiation Sources:
user/CEO.
7.7.1 X-Radiation Sources—Selection of appropriate X-ray
7.5 Image display monitors used for interpretation shall
voltage and current levels is dependent upon variables regard-
meet the following requirements as a minimum. Alternate
ing the specimen being examined (material type and thickness)
image displays or requirements may be used with CEO
and exposure time. The suitability of these exposure param-
approval.
eters shall be demonstrated by attainment of the required
7.5.1 The minimum brightness as measured off the image
radiographic quality level and compliance with all other
display monitor screen at maximum Digital Driving Level
requirements stipulated herein.
(DDL) shall be 250 cd/m .
7.7.2 Gamma Radiation Sources—Isotope sources that are
7.5.2 The minimum contrast as determined by the ratio of
used shall be capable of demonstrating the required radio-
the image display monitor screen brightness at the maximum
graphic quality level.
DDL compared to the screen brightness at the minimum DDL
7.8 Photometers or Light Meters—Photometers or light
shall be 250:1.
meters used for determining display monitor brightness and
7.5.3 The image display monitor shall be capable of dis-
contrast and ambient background light, shall meet the require-
playing linear patterns of alternating pixels at full contrast in
ments of ANSI/NCSL Z540-3 or ISO/CIE 19476.
both the horizontal and vertical directions without aliasing.
7.5.4 Theimagedisplaymonitorshallbefreeofdiscernable
8. Equipment Monitoring Requirements
geometric distortion.
7.5.5 The image display monitor shall be free of screen 8.1 The image display monitor shall be checked in accor-
flicker, characterized by high frequency fluctuation of high dance with Appendix X1.
contrast image details. 8.1.1 Image Viewing Stations—Image viewing stations shall
7.5.6 The image display monitor shall be capable of dis-
be arranged to exclude any objectionable illuminance that
playing a 5 % DDL block against a 0 % DDL background and could cause a reflective glare from the display monitor and
simultaneously displaying a 95 % DDL block against a 100 %
shall have light controls to achieve ambient (background)
background in a manner clearly perceptible to the user. An lighting levels of no greater than 30 lux.
image display test pattern, in accordance with the requirements
8.1.2 Ambient light shall be measured at the viewing
of SMPTE RP 133, shall be configured for the system display
surface with the display monitor off.
resolution and aspect ratio.Alternate test patterns may be used
8.2 Radiographic images shall be free of visible bad pixels
providedtheyincludethefeaturesdescribedinSMPTERP133
orotherartifactswhichmayinterferewithimageinterpretation
required to perform the quality tests specified in this practice.
(see Practices E2597/E2597M and E2737).
7.5.7 The image display monitor shall be capable of dis-
8.3 Detailed schedule and tests for monitoring the DDA
criminating the horizontal and vertical low contrast (1 %)
modulation patterns at the display center and each of the four performance over time shall be performed in accordance with
Practice E2737.
corner locations.
7.5.8 The image display monitor shall be capable of dis-
8.4 The user shall adopt the manufacturer’s recommenda-
playing no less than 256 unique shades of gray.
tions for DDA gain, offset and bad pixel identification and
7.6 Image Quality Indicators (IQI): calibration,methodologyandthefrequencythereof,andaltera-
7.6.1 IQIsshallbeinaccordancewitharecognizedstandard tions as needed defined by the CEO based on the object under
test.
or approved by the Cognizant Engineering Organization. Hole
plate type indicators shall comply with Practice E1025 or 8.4.1 In the event that any non-uniformities or artifacts
Practice E1742/E1742M, Annex 1. Wire type indicators shall
(other than bad pixels) appear in an image between recom-
be in accordance with Practice E747 and correlated to the hole mended intervals of gain and offset calibration, the detector is
type penetrameters in accordance with Practice E747.
to be recalibrated for gain and offset correction so that these
7.6.2 TheIQIshallbeconstructedfrommaterialinthesame anomaliesareremovedpriortocontinuingproductionimaging.
material group (see Practice E1025) as the material to be If these anomalies could be found to either mask a relevant
radiographically examined. If an IQI material of the same discontinuity or be interpreted as a relevant discontinuity, then
ϵ1
E2698 − 18
the effected product shall be re-imaged. When non- uniformi- 9.2 It shall be the responsibility of the user NDT facility to
ties and artifacts occur outside of the area of interest within an develop written procedures and examination techniques that
image, re-imaging is not required as they do not interfere with are capable of consistently producing the desired results and
interpretation. radiographic quality level. All written procedures shall be
approved by an individual qualified and certified as a Level 3
8.4.2 In the event that any detector-related non-uniformities
in Radiographic Testing in accordance with 5.1.1. When
or artifacts remain in the area of interpretation in a flat x-ray
required by contract or purchase order, the procedure and/or
field image (no object) after recalibration, then the detector
techniques shall be submitted to the CEO for approval. The
shall be tested in accordance with Practice E2737 for requali-
following items shall be addressed in the written documenta-
fication and long term stability testing, where a determination
tion:
will be made if the detector needs to be removed from service.
a) Name and address of the NDT facility, the date, and revision of the proce-
If the detector is removed from service, then the part or parts
dure.
under question will be re-examined with a fully qualified
b) Radiographic Image Identification scheme used to correlate the image to
detector, and this new detector will be used for future exami-
the part. If the examination procedures are similar for many components, a
master written procedure shall be used that covers the details common to
nations. If the detector is returned to service following testing
a variety of components.
with recommended changes to methodology, these changes
c) The thickness and type of material.
shall be approved by the CEO and implemented prior to the d) A drawing, sketch, or photograph of the general exposure setup showing
the object’s location and the IQI, with respect to the radiation source for
detector being placed back into service.
each view. The angle of the radiation beam in relation to the object, the
source to DDA distance, source to object distance, and any blocking or
8.5 If any new relevant clusters are identified, any parts
masking, if used shall be documented. For robotic or similar systems with
evaluated since the establishment of the previous bad pixel
hard fixturing and controlled scan plans, a drawing, sketch or photograph
is not required.
map shall be assessed to determine if the newly identified
e) For X-ray tube exposures; the model and manufacturer of the x-ray tube
relevant cluster had any impact on the proper disposition of the
and the focal spot size.
affected product, and whether re-examination of the product is
e.1) The nominal exposure: voltage, current, exposure time, frame rate, frames
averaged, beam and/or detector collimation, beam filters used including
required. When deemed necessary by the CEO, the detector
their locations (tube, part, detector, and so forth)
shall be tested in accordance with Practice E2737 for re-
f.) For radioisotope source exposures: the isotope type and source size.
qualification and for long term stability testing. A determina- f.1) The nominal exposure: source strength, exposure time, frame rate, frames
averaged, beam and/or detector collimation, beam filters used including
tion will then be made by the CEO if the detector needs to be
their locations (tube, part, detector, and so forth).
removed from service. If the detector is removed from service,
g.) The make, model, and manufacturer of the DDA used in the examination.
detector
thenthepart(s)underquestionwillbere-examinedwithafully The detectors iSR shall be addressed on the procedure, technique,
b
or other related documentation along with the detector mode (full
qualified detector, and this detector will be used for future
resolution, pixel binned, and so forth) and the detector’s gain setting (as
examinations. If the detector is returned to service following
available).
h.) The geometric magnification factor used, including source to object and
testing with recommended changes to methodology, these
object to detector distances and the measured or calculated total image
changes shall be approved by the CEO and implemented prior
unsharpness.
to the detector being placed back into service.
i.) The IQI size and type, the required radiographic quality leve
...