ASTM E1742/E1742M-23

Standard Practice for Radiographic Examination

SIGNIFICANCE AND USE
4.1 This practice establishes the basic parameters for the application and control of the radiographic method. This practice is written so it can be specified on the engineering drawing, specification, or contract. It is not a detailed how-to procedure to be used by the NDT facility and, therefore, must be supplemented by a detailed procedure (see 6.1). Practices E1030/E1030M, E1032, and E1416 contain information to help develop detailed technique/procedure requirements.
SCOPE
1.1 This practice2 covers the minimum requirements for radiographic examination for metallic and nonmetallic materials.  
1.2 Applicability—The criteria for the radiographic examination in this practice are applicable to all types of metallic and nonmetallic materials. When specified, it may be used for radiographic inspection of metallic or non-metallic materials, weldments, castings, and brazed materials. The requirements expressed in this practice are intended to control the quality of the radiographic images and are not intended to establish acceptance criteria for parts and materials.  
1.3 Basis of Application—There are areas in this practice that may require agreement between the cognizant engineering organization and the supplier, or specific direction from the cognizant engineering organization. These items should be addressed in the purchase order or the contract.  
1.3.1 DoD contracts.  
1.3.2 Personnel qualification, 5.1.1.  
1.3.3 Agency qualification, 5.1.2.  
1.3.4 Digitizing techniques, 5.4.5.  
1.3.5 Alternate image quality indicator (IQI) types, 5.5.3.  
1.3.6 Examination sequence, 6.6.  
1.3.7 Non-film techniques, 6.7.  
1.3.8 Radiographic quality levels, 6.9.  
1.3.9 Optical density, 6.10.  
1.3.10 IQI qualification exposure, 6.13.3.  
1.3.11 Non-requirement for IQI, 6.18.  
1.3.12 Examination coverage for welds, A2.2.2.  
1.3.13 Electron beam welds, A2.3.  
1.3.14 Geometric unsharpness, 6.23.  
1.3.15 Responsibility for examination, 6.27.1.  
1.3.16 Examination report, 6.27.2.  
1.3.17 Retention of radiographs, 6.27.8.  
1.3.18 Storage of radiographs, 6.27.9.  
1.3.19 Reproduction of radiographs, 6.27.10 and 6.27.10.1.  
1.3.20 Acceptable parts, 6.28.1.  
1.4 Units—The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with 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 responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.6 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: 14-Dec-2023
• ICS: 19.100 - Non-destructive testing
• ICS: 77.040.20 - Non-destructive testing of metals
• Technical Committee: E07 - Nondestructive Testing
• Drafting Committee: E07.01 - Radiography (X and Gamma) Method

Relations

• Replaces: ASTM E1742/E1742M-18 - Standard Practice for Radiographic Examination
• Effective Date: 15-Dec-2023
• Refers: ASTM E1316-24 - Standard Terminology for <?Pub Dtl?>Nondestructive Examinations
• Effective Date: 01-Feb-2024
• Refers: ASTM E1316-23b - Standard Terminology for Nondestructive Examinations
• Effective Date: 01-Sep-2023
• Referred By: ASTM E2982-21 - Standard Guide for Nondestructive Examination of Thin-Walled Metallic Liners in Filament-Wound Pressure Vessels Used in Aerospace Applications
• Effective Date: 15-Dec-2023
• Referred By: ASTM E1161-21 - Standard Practice for Radiographic Examination of Semiconductors and Electronic Components
• Effective Date: 15-Dec-2023
• Referred By: ASTM E1030/E1030M-21 - Standard Practice for Radiographic Examination of Metallic Castings
• Effective Date: 15-Dec-2023
• Referred By: ASTM E2981-21 - Standard Guide for Nondestructive Examination of Composite Overwraps in Filament Wound Pressure Vessels Used in Aerospace Applications
• Effective Date: 15-Dec-2023
• Referred By: ASTM E94/E94M-22 - Standard Guide for Radiographic Examination Using Industrial Radiographic Film
• Effective Date: 15-Dec-2023
• Referred By: ASTM F629-20 - Standard Practice for Radiography of Cast Metallic Surgical Implants
• Effective Date: 15-Dec-2023
• Referred By: ASTM F2895-20 - Standard Practice for Digital Radiography of Cast Metallic Implants
• Effective Date: 15-Dec-2023
• Referred By: ASTM E2737-23 - Standard Practice for Digital Detector Array Performance Evaluation and Long-Term Stability
• Effective Date: 15-Dec-2023
• Referred By: ASTM E2533-21 - Standard Guide for Nondestructive Examination of Polymer Matrix Composites Used in Aerospace Applications
• Effective Date: 15-Dec-2023
• Referred By: ASTM E2903-18 - Standard Test Method for Measurement of the Effective Focal Spot Size of Mini and Micro Focus X-ray Tubes
• Effective Date: 15-Dec-2023
• Referred By: ASTM E2698-18e1 - Standard Practice for Radiographic Examination Using Digital Detector Arrays
• Effective Date: 15-Dec-2023

Overview

ASTM E1742/E1742M-23, Standard Practice for Radiographic Examination, is a foundational document from ASTM International focused on specifying the basic parameters for radiographic testing of metallic and nonmetallic materials. This practice establishes the minimum requirements for conducting radiographic examinations in a range of industrial applications, providing guidance for the application and control of radiographic methods as well as the necessary qualifications for personnel and agencies involved in nondestructive testing (NDT). ASTM E1742/E1742M-23 is designed to be referenced in engineering drawings, specifications, or contracts but must be used in conjunction with detailed procedural documentation developed by NDT facilities.

Key Topics

• Minimum Requirements: Lays out the essential criteria for radiographic examination across all types of metallic and nonmetallic materials, including weldments, castings, and brazed assemblies.
• Radiographic Quality Control: Addresses standards for the quality of radiographic images without setting acceptance criteria for part/material conformance.
• Personnel & Agency Qualification: Highlights the necessity for qualification in accordance with recognized standards (such as NAS 410, SNT-TC-1A, ANSI/ASNT-CP-189, or ISO 9712).
• Procedure Development: Emphasizes that this standard is not a substitute for detailed technical procedures, which must be developed to address specific technique requirements.
• Application Flexibility: Stresses the need for agreement and clear communication between engineering organizations and suppliers regarding requirements such as examination sequence, image quality indicator (IQI) types, and non-film techniques.
• Measurement Units: States that both SI and inch-pound units are considered standard, but should not be mixed to avoid non-conformance.
• Safety Considerations: Reminds users of their responsibility to establish health, safety, and environmental protocols and observe regulatory limitations.

Applications

ASTM E1742/E1742M-23 is widely utilized across industries that rely on radiographic examination for quality control and safety, including aerospace, defense, automotive, energy, and manufacturing. Its applications include:

• Weld Inspection: Ensuring weld integrity in pipelines, pressure vessels, and structural components.
• Casting and Forging Examination: Detecting internal flaws such as porosity, shrinkage, and inclusions in both ferrous and non-ferrous parts.
• Quality Assurance for Components: Verifying the internal and external consistency of parts where internal defects could compromise performance or safety.
• Contract Compliance: Providing a reference point for specifying radiographic requirements in procurement, project management, and manufacturing contracts.
• Non-Film and Digital Techniques: Accommodating emerging digital radiography and radioscopic approaches, with flexibility for digitizing and other advanced methodologies where approved.

Related Standards

ASTM E1742/E1742M-23 works in concert with various referenced standards and industry documents to create a robust framework for radiographic examination:

• ASTM E94/E94M: Guide for Radiographic Examination Using Industrial Radiographic Film.
• ASTM E747: Practice for Design, Manufacture and Material Grouping of Wire Image Quality Indicators (IQI).
• ASTM E1030/E1030M: Practice for Radiographic Examination of Metallic Castings.
• ASTM E1032: Practice for Radiographic Examination of Weldments Using Industrial X-Ray Film.
• ASTM E1416: Practice for Radioscopic Examination of Weldments.
• NAS 410 / SNT-TC-1A / ANSI/ASNT-CP-189 / ISO 9712: Standards for qualification and certification of NDT personnel.
• AWS A2.4: Standard Symbols for Welding, Brazing, and Nondestructive Examination.
• ISO 5579, ISO 9712: International standards for radiographic examination and NDT personnel qualification.

ASTM E1742/E1742M-23 is essential for organizations aiming to ensure the reliability, safety, and regulatory compliance of their radiographic examination processes. It provides the baseline framework for industry best practices in nondestructive testing, helping to standardize procedures and streamline communication between manufacturers, engineering organizations, and NDT providers.

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.
Designation: E1742/E1742M − 23
Standard Practice for
Radiographic Examination
This standard is issued under the fixed designation E1742/E1742M; 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.
This standard has been approved for use by agencies of the U.S. Department of Defense.
1. Scope* 1.3.18 Storage of radiographs, 6.27.9.
2 1.3.19 Reproduction of radiographs, 6.27.10 and 6.27.10.1.
1.1 This practice covers the minimum requirements for
1.3.20 Acceptable parts, 6.28.1.
radiographic examination for metallic and nonmetallic materi-
als. 1.4 Units—The values stated in either SI units or inch-
pound units are to be regarded separately as standard. The
1.2 Applicability—The criteria for the radiographic exami-
values stated in each system may not be exact equivalents;
nation in this practice are applicable to all types of metallic and
therefore, each system shall be used independently of the other.
nonmetallic materials. When specified, it may be used for
Combining values from the two systems may result in non-
radiographic inspection of metallic or non-metallic materials,
conformance with the standard.
weldments, castings, and brazed materials. The requirements
1.5 This standard does not purport to address all of the
expressed in this practice are intended to control the quality of
safety concerns, if any, associated with its use. It is the
the radiographic images and are not intended to establish
responsibility of the user of this standard to establish appro-
acceptance criteria for parts and materials.
priate safety, health, and environmental practices and deter-
1.3 Basis of Application—There are areas in this practice
mine the applicability of regulatory limitations prior to use.
that may require agreement between the cognizant engineering
1.6 This international standard was developed in accor-
organization and the supplier, or specific direction from the
dance with internationally recognized principles on standard-
cognizant engineering organization. These items should be
ization established in the Decision on Principles for the
addressed in the purchase order or the contract.
Development of International Standards, Guides and Recom-
1.3.1 DoD contracts.
mendations issued by the World Trade Organization Technical
1.3.2 Personnel qualification, 5.1.1.
Barriers to Trade (TBT) Committee.
1.3.3 Agency qualification, 5.1.2.
1.3.4 Digitizing techniques, 5.4.5.
2. Referenced Documents
1.3.5 Alternate image quality indicator (IQI) types, 5.5.3.
1.3.6 Examination sequence, 6.6. 2.1 The following documents form a part of this practice to
the extent specified herein:
1.3.7 Non-film techniques, 6.7.
1.3.8 Radiographic quality levels, 6.9.
2.2 ASTM Standards:
1.3.9 Optical density, 6.10.
E94/E94M Guide for Radiographic Examination Using In-
1.3.10 IQI qualification exposure, 6.13.3.
dustrial Radiographic Film
1.3.11 Non-requirement for IQI, 6.18.
E543 Specification for Agencies Performing Nondestructive
1.3.12 Examination coverage for welds, A2.2.2.
Testing
1.3.13 Electron beam welds, A2.3.
E747 Practice for Design, Manufacture and Material Group-
1.3.14 Geometric unsharpness, 6.23.
ing Classification of Wire Image Quality Indicators (IQI)
1.3.15 Responsibility for examination, 6.27.1.
Used for Radiology
1.3.16 Examination report, 6.27.2.
E801 Practice for Controlling Quality of Radiographic Ex-
1.3.17 Retention of radiographs, 6.27.8.
amination of Electronic Devices
E999 Guide for Controlling the Quality of Industrial Radio-
graphic Film Processing
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.
Current edition approved Dec. 15, 2023. Published January 2024. Originally For referenced ASTM standards, visit the ASTM website, www.astm.org, or
approved in 1995. Last previous edition approved in 2018 as E1742/E1742M – 18. contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
DOI: 10.1520/E1742_E1742M-23. Standards volume information, refer to the standard’s Document Summary page on
This practice replaced MIL-STD-453. the ASTM website.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
E1742/E1742M − 23
E1025 Practice for Design, Manufacture, and Material 3. Terminology
Grouping Classification of Hole-Type Image Quality In-
3.1 Definitions—Definitions relating to radiographic
dicators (IQI) Used for Radiography
examination, which appear in Terminology E1316, shall apply
E1030/E1030M Practice for Radiographic Examination of
to the terms used in this practice.
Metallic Castings
3.1.1 Optical density is the correct term for assessing the
E1032 Practice for Radiographic Examination of Weldments
developed film obtained from a penetrating radiation film
Using Industrial X-Ray Film
inspection. Historically, the terms film or radiographic density,
E1079 Practice for Calibration of Transmission Densitom-
or both, have been used to describe the measurements taken
eters
from viewing the images, but the current definition of film
E1165 Test Method for Measurement of Focal Spots of
density, in Terminology E1316, is “the quantitative measure of
Industrial X-Ray Tubes by Pinhole Imaging
diffuse optical light transmission (optical density, blackening)
E1254 Guide for Storage of Radiographs and Unexposed
through a developed film.” In addition, with the advent of
Industrial Radiographic Films
digital radiography, these historical terms may cause confusion
E1255 Practice for Radioscopy
to those utilizing more than the film technique. For standards
E1316 Terminology for Nondestructive Examinations
purposes, the correct term is optical density and has been
E1390 Specification for Illuminators Used for Viewing In-
replaced throughout this standard.
dustrial Radiographs
3.2 Definitions of Terms Specific to This Standard:
E1416 Practice for Radioscopic Examination of Weldments
3.2.1 component, n—the part(s) or element of a system,
E1815 Test Method for Classification of Film Systems for
assembled or processed to the extent specified by the drawing,
Industrial Radiography
purchase order, or contract.
E2033 Practice for Radiographic Examination Using Com-
puted Radiography (Photostimulable Luminescence
3.2.2 energy, n—a property of radiation that determines its
Method) penetrating ability. In X-ray radiography, energy machine
E2698 Practice for Radiographic Examination Using Digital
rating is determined by kilovolts (keV), million electronvolts
Detector Arrays (MeV). In gamma ray radiography, energy is a characteristic of
the source used.
2.3 AWS Document:
AWS A2.4 Standard Symbols for Welding, Brazing, and
3.2.3 like section, n—a separate section of material that is
Nondestructive Examination
similar in shape and cross section to the component or part
being radiographed, and is made of the same or radiographi-
2.4 NCRP Documents:
cally similar material.
NCRP 116 Limitation of Exposure to Ionizing Radiation
NCRP 144 Radiation Protection for Particle Accelerator
3.2.4 material group, n—materials that have the same pre-
Facilities
dominant alloying elements and which can be examined using
NCRP 147 Structural Shielding Design for Medical X-ray
the same IQI. A listing of common material groups is given in
Imaging Facilities
Practice E1025.
2.5 ANSI/ISO Standards:
3.2.5 NDT facility, n—the NDT facility performing the
ANSI/NCSL Z540-3 Requirements for the Calibration of
radiographic examination.
Measuring and Test Equipment
3.2.6 radiographic quality level, n—the ability of a radio-
ISO 10012 Measurement Management Systems—
graphic procedure to demonstrate a certain IQI sensitivity.
Requirements for Measurement Processes and Measuring
Equipment
4. Significance and Use
ISO 5579 Non-Destructive Testing-Radiographic Examina-
tion of Metallic Materials by X-and Gamma-Rays-Basic
4.1 This practice establishes the basic parameters for the
Rules
application and control of the radiographic method. This
practice is written so it can be specified on the engineering
NOTE 1—DoD Contracts: Unless otherwise specified, the issues of the
drawing, specification, or contract. It is not a detailed how-to
documents that are DoD adopted are those listed in the issue of the
procedure to be used by the NDT facility and, therefore, must
DoDISS (Department of Defense Index of Specifications and Standards)
cited in the solicitation. be supplemented by a detailed procedure (see 6.1). Practices
NOTE 2—Order of Precedence: In the event of conflict between the text
E1030/E1030M, E1032, and E1416 contain information to
of this practice and the references cited herein, the text of this practice
help develop detailed technique/procedure requirements.
takes precedence. Nothing in this practice, however, supersedes applicable
laws and regulations unless a specific exemption has been obtained.
5. General Practice
5.1 Qualification:
5.1.1 Personnel Qualification—If specified in the contrac-
Available from American Welding Society (AWS), 550 NW LeJeune Rd.,
Miami, FL 33126, http://www.aws.org.
tual agreement, personnel performing examinations to this
Available from National Council on Radiation Protection and Measurements,
practice shall be qualified in accordance with a nationally or
NCRP Publications, 7910 Woodmount Ave., Suite 800, Bethesda, MD 20814.
internationally recognized NDT personnel qualification prac-
Available from American National Standards Institute (ANSI), 25 W. 43rd St.,
4th Floor, New York, NY 10036, http://www.ansi.org. tice or standard and certified by the employer or certifying
E1742/E1742M − 23
agency, as applicable. The practice or standard used shall be light leaks into the film holder and produces images on the
identified in the contractual agreement between the using radiograph, the radiograph need not be rejected unless the
parties. images obscure, or interfere with, the area of interest. If the
5.1.2 Agency Evaluation—If specified in the contractual film holder exhibits light leaks it shall be further repaired
before use, or discarded. Film holders and cassettes should be
agreement, NDT agencies shall be qualified and evaluated in
accordance with Specification E543. The applicable revision of routinely examined for cracks or other defects to minimize the
likelihood of light leaks.
Specification E543 shall be specified in the contractual agree-
ment. 5.4.3 Intensifying Screens:
5.4.3.1 Lead Foil Screens—When using a source greater
5.2 Laboratory Installations:
than 150 keV, intensifying screens of the lead foil type are
5.2.1 Safety—The premises and equipment shall present no
recommended. Screens shall have the same area dimensions as
hazards to the safety of personnel or property. NCRP 147,
the film being used and shall be in intimate contact with the
NCRP 116, and NCRP 144 may be used as guides to ensure
film during exposure. Recommended screen thicknesses are
that radiographic procedures are performed so that personnel
listed in Table 1 for the applicable voltage range being used.
shall not receive a radiation dosage exceeding the maximum
Screens shall be free from any cracks, creases, scratches, or
permitted by city, state, or national codes.
foreign material that could render undesirable nonrelevant
5.2.2 Radiographic Exposure Areas—Radiographic expo-
images on the radiograph.
sure areas shall be clean and equipped so that acceptable
5.4.3.2 Fluorescent, Fluorometallic, or Other Metallic
radiographs may be produced in accordance with the require-
Screens—Fluorescent, fluorometallic, or other metallic screens
ments of this practice.
may be used. However, they must be capable of demonstrating
5.2.3 Darkroom—Darkroom facilities, including equipment
the required penetrameter (IQI) sensitivity. Fluorescent or
and materials, shall be capable of producing uniform radio-
fluorometallic screens may cause limitations in image quality
graphs free of blemishes or artifacts, which might interfere
(see Guide E94/E94M, Appendix X1).
with interpretation in the area of interest.
5.4.4 Film Viewers—Viewers used for final interpretation
5.2.4 Film Viewing Area—The film viewing room or enclo-
shall meet the following requirements:
sure shall be an area with subdued lighting to preclude
5.4.4.1 The viewer shall contain a variable control to allow
objectionable reflective glare from the surface of the radio-
the selection of optimum intensities for radiographs with
graph under examination (see 6.27.6).
varying optical densities.
5.3 Materials: 5.4.4.2 The light source shall have sufficient intensity to
enable viewing of optical densities in the area of interest (see
5.3.1 Film—Film selection for production radiographs
6.27.4).
should be based on radiation source energy level, part
thickness/configuration, and image quality. Only film systems
having cognizant engineering organization approval or meeting
the class requirements of Test Method E1815 shall be used.
A
TABLE 1 Lead Screen Thickness
5.3.1.1 Nonfilm Recording Media—Other recording media
Energy Range/ Front Screen Back Screen Front and
B
may be used when approved by the cognizant engineering Isotopes Minimum Back Screens
in. in. mm
organization.
C D
0 keV – 150 keV 0.000 to 0.001 0.005 0–0.15
5.3.2 Film Processing Solutions—Production radiographs D
151 keV – 200 keV 0.000 to 0.005 0.005 0.02–0.15
shall be processed in solutions capable of consistently produc- 201 keV – 320 keV 0.001 to 0.010 0.005 0.02–0.2
Se-75 0.001 to 0.010 0.005 0.1–0.2
ing radiographs that meet the requirements of this practice.
321 keV – 450 keV 0.005 to 0.015 0.01 0.1–0.2
Solution control shall be in accordance with Annex A4. Guide
Ir-192 0.005 to 0.015 0.01 0.02–0.2
E999 should be consulted for guidance on film processing. 451 keV – 2 MeV 0.005 to 0.020 0.01 0.1–0.5
Co-60 0.005 to 0.020 0.01 0.1–0.5
5.4 Equipment:
2 MeV – 4 MeV 0.010 to 0.020 0.01 0.1–0.5
4 MeV – 10 MeV 0.010 to 0.030 0.01 0.5–1.0
5.4.1 Radiation Sources:
10 MeV – 25 MeV 0.010 to 0.050 0.01 1.0–2.0
5.4.1.1 X-Radiation Sources—Selection of appropriate
A
The lead screen thickness listed for the various energy ranges are recom-
X-ray voltage and current levels is dependent upon variables
mended thicknesses and not required thicknesses. Other thicknesses and mate-
regarding the specimen being examined (material type and rials may be used provided the required radiographic quality level, contrast, and
optical density are achieved.
thickness) and exposure time. The suitability of these exposure
B
Lead screen thicknesses in accordance with EN 444 and ISO 5579 in SI units.
parameters shall be demonstrated by attainment of the required
For energy ranges of Co-60 and 451 keV to 4 MeV, steel or copper screens of
radiographic quality level and compliance with all other 0.1 mm to 0.5 mm may be used. For energy ranges above 4 MeV to 10 MeV,
0.5 mm to 1.0 mm steel or copper or up to 0.5 mm tantalum screens are
requirements stipulated herein.
recommended. Additional back scatter shielding may be achieved by additional
5.4.1.2 Gamma Radiation Sources—Isotope sources that are
lead screens behind the cassettes.
C
Prepackaged film with lead screens may be used from 80 keV to 150 keV. No
used shall be capable of demonstrating the required radio-
lead screens are recommended below 80 keV. Prepackaged film may be used at
graphic quality level.
higher energy levels provided the contrast, optical density, radiographic quality
5.4.2 Film Holders and Cassettes—Film holders and cas- level, and backscatter requirements are achieved. Additional intermediate lead
screens may be used for reduction of scattered radiation at higher energies.
settes shall be light tight, constructed of materials that do not
D
No back screen is required provided the backscatter requirements of 6.22 are
interfere with the quality or sensitivity of radiographs, and
met.
shall be handled properly to reduce damage. In the event that
E1742/E1742M − 23
TABLE 2 Process Control Checks
5.4.4.3 The light enclosure shall be designed to provide a
uniform brightness level over the entire viewing screen. Check Frequency Paragraph
A,B
Discontinuity Image Measuring 5.4.7
5.4.4.4 The viewer shall be equipped with a suitable fan,
Device
blower, or other means to provide stable temperature at the
Image Quality Indicators:
Certified When procured 5.5.4
viewing port to avoid damaging the radiographic film while
C
Check (Condition) prior to use 5.5.4
viewing.
Automatic Processing:
D
5.4.4.5 The viewer shall be equipped with a translucent Processor Performance Daily A4.2.1
D
Base Fog Daily A4.2.5
material front in each viewing port, except for localized
C
Developer Temperature Prior to use A4.2.3
high-intensity viewing of high-optical-density radiographs ar- E
Replenishment Rate A4.2.2
F
Transport Speed A4.2.4
eas through separate viewing ports, apertures, or other suitable
Manual Processing:
openings.
Processing Performance Daily A4.3.1
5.4.4.6 A set of opaque masks, an iris-type aperture, or any
Base plus Fog Monthly A4.2.5
G
Developer Temperature Prior to use A4.3.2
other method to reduce the viewing area to suit the size of the
Densitometer:
area of interest shall be provided.
H
Verification Check Each shift 6.27.5
I
Calibration Check 3 months 6.27.5
5.4.4.7 Illuminators procured to, or meeting the require-
Light Meters Annual 6.27.4/6.27.6
ments of, Specification E1390 are acceptable for use.
Viewer Light Intensity 6.27.4
5.4.5 Digitizing Techniques—The use of film digitizing
B
Thermometer Calibration 6 months A4.2.3
techniques is acceptable when approved by the cognizant
J
Ambient Visible Light 6 months 6.27.6
engineering organization.
Stepwedge Calibration Annual 6.27.5
5.4.6 Densitometers—The densitometer shall be capable of
A
Optical Devices—When procured; mechanical devices (see Footnote B).
measuring the light transmitted through a radiograph with an
B
Calibrated and recorded in accordance with ANSI Z540-3, or ISO 10012, as
optical density up to 4.0 with a unit resolution of 0.02. When
applicable.
C
optical densities greater than 4.0 are permitted, a densitometer
Documentation of this check not required.
D
May be extended to weekly when substantiated by actual technical/reliability
capable of measuring optical densities up to the maximum
data and approved by the cognizant engineering organization.
optical density permitted is required.
E
Measured and recorded when solutions are changed during preventative
5.4.7 Film Viewing Aids—Magnifiers shall be available to maintenance or repair.
F
Measured and recorded during preventative maintenance or repair.
provide magnification between 3× and 10× to aid in interpre-
G
Temperatures shall be checked prior to each use. Daily documentation of this
tation and determine indication size, as applicable. The specific
check is required.
H
magnifier used should be determined by the interpretation Each shift or when maintenance is performed (bulb or aperture changed).
I
Every three months or whenever the densitometer verification check is not within
requirements. Devices used for determining defect size shall be
tolerance.
J
calibrated as scheduled in Table 2.
Fixed viewing locations with acceptable and controlled ambient lighting condi-
tions need not be re-verified as long as those conditions are maintained.
5.4.8 Luminance/illuminance light meters are procured and
calibrated in accordance with Table 2.
5.5 Image Quality Indicators (IQIs):
5.5.3 Alternate IQI Types—The use of other types of IQIs,
5.5.1 Image Quality Indicators (IQIs)—The IQIs shall be in
or modifications to types specified in 5.5.1, is permitted upon
accordance with contract requirements. Hole-type IQIs in
approval of the cognizant engineering organization. Details of
accordance with this practice, Practice E1025, or the alternate
design of Annex A1, or wire-type IQIs in accordance with the design, materials designation, and thickness identification
of the IQIs shall be in the written procedure, or documented on
Practice E747, shall be used when IQIs are required. If wire
IQIs are used, they shall be correlated to hole-type radio- a drawing that shall be referenced in the written procedure (see
6.1).
graphic quality levels in accordance with Practice E747. For
the radiography of electronic devices, Practice E801 shall be 5.5.4 IQI Control—The IQIs shall be procured or fabricated
to the requirements of Practice E1025, or the alternate design
used.
of Annex A1, as applicable, with a manufacturer’s certification
5.5.2 Radiographically Similar IQI Material—Materials
of compliance with respect to alloy and dimensions. Users
shall be considered radiographically similar if the following
shall visually inspect IQIs for damage, chamfering, and clean-
requirements are satisfied. Two blocks of equal thickness, one
liness in accordance with Table 2.
of the material to be radiographed and one of the material of
which the IQIs are made, shall be exposed together on the same
6. Detail Requirements
film at the lowest energy level to be used for production
radiographs. If the optical density of the material to be 6.1 Written Procedure—It shall be the responsibility of the
radiographed is within the range from 0 to +15 % of the IQI NDT facility to develop a workable examination technique
material (that is, the IQI is slightly more attenuating), the IQI recorded as a written procedure that is capable of consistently
material shall be considered radiographically similar and may producing the desired results and radiographic quality level.
be used to fabricate IQIs for examination of the production When required by contract or purchase order, the procedure
material. The optical density readings shall be between 2.0 and shall be submitted to the cognizant engineering organization
4.0 for both materials. An IQI with a lower radiation attenua- for approval. The written procedure shall contain, as a
tion may be used. minimum, the following information:
E1742/E1742M − 23
6.1.1 A drawing, sketch, or photograph of the component 6.4 Radiographic Identification—Each radiograph shall
showing the location of the film and IQI with respect to the carry the identification or serial number of the component and
radiation source for each exposure. view number, when multiple views are taken. Each radiograph
6.1.2 The angle of the radiation beam in relation to the shall also carry the identification of the NDT facility examining
component, the source-to-film distance, and any blocking or
the component and the date of the examination. Radiographs of
masking, if used. a repair area shall be identified with R1, R2, R3, and so forth,
6.1.3 Part zones, if applicable, should be included (see 6.2).
indicating the number of times that repairs were attempted.
This may be accomplished through drawings and tables or by Alternative schemes may be used for identification of repair
reference to documents where such information is found.
radiographs so long as each film is clearly identified to relate to
6.1.4 The nominal exposure for X-ray machines, the
a particular repair area. For explosives and propellants, the
voltage, milliamps, time (or rads as applicable), and effective
conditioning temperature shall be identified on each X-ray film
focal spot size. For radioisotope sources, the isotope type,
if the ordnance has been conditioned to a temperature other
source strength (curies), exposure time, and source size.
than facility ambient for purposes of examination.
6.1.5 Film designation (for example, brand, type, and pro-
6.5 Examination and Coverage—The number of parts
cessing parameters), intensifying screens (for example, type
examined, and the radiographic coverage of each part shall be
and thickness of screens), or filters (for example, filter material,
as specified by drawings, radiographic techniques, radio-
thickness, and location) if used, film loading instructions (for
graphic manuals, handbooks for aircraft technical orders, or
example, when using multiple film exposure techniques), and
other specifications, as applicable. Areas to be examined shall
the desired optical density range.
be identified on the drawing by using the symbols in accor-
6.1.6 Thickness and type of material.
dance with AWS A2.4 or other systems of designations that are
6.1.7 The IQI size and type, and the required radiographic
easily identified on the drawing. If the number of parts to be
quality level. If alternate IQIs are used (see 5.5.3), include
examined and the amount of coverage of each part is not
details of the design or reference to documents where such
specified, all parts shall be examined and shall receive 100 %
information is found.
radiographic coverage.
6.1.8 Thickness and type of material for shims or blocks, or
both, if used.
6.6 Examination Sequence—The sequence for radiographic
6.1.9 Name and address of the NDT facility and the date, or
examination in the production operation should be specified in
revision, of the procedure.
the manufacturing or assembly process specification, contract,
6.1.10 Radiographic identification scheme used to correlate
or purchase order. If not specified, radiographic examination
part-to-film. If the examination procedures are similar for
shall be performed at a stage in the process of manufacturing
many components, a master written procedure may be used
or assembly at which discontinuities can be detected. Radio-
that covers the details common to a variety of components. All
graphic examination may be performed before heat treatment,
written procedures shall be approved by an individual qualified
provided liquid penetrant or magnetic particle examinations are
and certified as a Level III for radiography in accordance with
performed after heat treatment.
5.1.1.
6.7 Nonfilm Techniques—When permitted by purchase
6.2 Acceptance Requirements—When examination is per-
order, contract, or specification, radioscopic/radiological ex-
formed in accordance with this practice, engineering drawings,
aminations using nonfilm techniques shall be in accordance
specifications, or other applicable documents shall indicate the
with Practices E1255, E2033 or E2698 or a nonfilm specifica-
criteria by which the components are judged acceptable.
tion approved by the cognizant engineering organization as
Complex components may be divided into zones and separate
required. Prior approval shall be obtained from the Level III
criteria assigned to each zone in accordance with its design
radiographer of the cognizant engineering organization (see
requirements. When used, direct references to ASTM reference
5.1.1).
radiographic standards shall include the grade level for each
6.8 Multi-Film Techniques—Film techniques with two or
type of discontinuity permitted for each part or zone.
more films of the same or different speeds in the same film
NOTE 3—Information on reference radiographs can be obtained from
holder, to be used in either single or superimposed film
the Annual Book of ASTM Standards, Vol 03.03 or from ASTM Head-
viewing, shall be permitted provided that the applicable radio-
quarters.
graphic quality level, and optical density requirements (see 6.9
6.3 Surface Preparation—Components may be examined
and 6.10), are achieved for the area of interest.
without surface preparation or conditioning except as required
to remove surface conditions that may interfere with proper 6.9 Radiographic Quality Levels—The five quality levels
interpretation of radiographs.
listed in Table 3 may be assigned on the basis of IQI thickness
6.3.1 Castings, forgings, and weldments may be radio- and the perceptibility of one, two, or three holes in the
graphed in the as-cast, as-forged, or as-welded conditions
hole-type IQI image on the radiograph. If the quality level is
provided the following requirements are met. not specified on the drawing or other applicable documents, it
6.3.1.1 For castings and forgings, the surface condition shall
shall be Level 2-2T. Unless otherwise specified by the cogni-
not interfere with evaluation. zant engineering organization, hole-type IQIs used for exami-
6.3.1.2 Accessible surfaces of welds shall be prepared in nation of material 0.25 in. [6.35 mm] or less in thickness shall
accordance with A2.1. be 0.005 in. [0.127 mm] minimum thickness.
E1742/E1742M − 23
TABLE 3 Quality Levels of Examination
6.10 Optical Density—For single-film viewing, the optical
Radiographic Maximum IQI Minimum Hole Equivalent IQI density shall be ≥1.5 in the area of interest. Where superim-
IQI Designation
A B C
Quality Level Thickness, % Diameter Sensitivity, %
posed radiograph viewing is used, the optical density of the
00 1–1T 1 1T 0.7
superimposed radiographs shall be from 2.0 in the area of
0 1–2T 1 2T 1.0
interest, and each individual radiograph shall not have an
1 2–1T 2 1T 1.4
2 2–2T 2 2T 2.0 optical density below 1.0 in the area of interest. Optical
3 2–4T 2 4T 2.8
densities above 4.0 are permitted when agreed upon between
A
Expressed as a percentage of material thickness.
the cognizant engineering organization and the NDT facility
B
Expressed as multiple thickness of IQI.
(see Note 1 of Fig. 1). In no case shall the maximum optical
C
Equivalent IQI sensitivity is that thickness of the IQI expressed as a percentage
of the specimen thickness in which a 2T hole would be clearly visible under the density exceed 4.5. For single-film viewing, optical densities
same radiographic conditions.
less than 1.5 are permitted only when items not requiring an
IQI (see 6.18) are examined. The maximum readable optical
density depends on the film viewer used and its maximum
NOTE 1—This figure is a depiction of the abscissa axis: Maximum Allowable Optical Density versus ordinate axis: Candela/m and footlamberts in
graphical format from tabular data derived from Specification E1390 and ISO 5580 (also known as EN 25580). Conversion from tabular data to a graph
accounts for the step in the line. For Film Viewer Output of 10 000 candela/m (2919 Footlamberts), the Maximum Allowable Optical Density shall be
3.0. Regarding the ordinate axis: Candela/m , the minimum luminance level required for the average human eye to achieve photopic eye response (that
is where maximum resolution and contrast discrimination occurs) is at 10 candela/m . At levels below this value the eye responds scotopically which
means lower contrast discrimination and resolution. While photopic vision typically occurs at a threshold of 10 candela/m for the average human eye,
this curve takes advantage of the fact that at lower optical densities most viewers can achieve an amount of light that guarantees that virtually all operators
will be viewing film in the photopic vision mode, that is 30 candela/m for optical densities <2.5. A theoretical advantage of this curve is that it
compensates for the reduced contrast sensitivity of radiographic film at lower optical densities.
NOTE 2—NDT film systems, classified corresponding to Test Method E1815 system classes “Special, I and II,” with or without lead screens, are suitable
for the extended viewing range above an optical density of 4, due to their high gradient (G >6) at D = 4 above fog and base. These double sided
D-D0 = 4
NDT film systems have a high silver content and do not saturate as early as medical and classes III, W-A, W-B and W-C film systems. The basic advantage
of increasing the optical density is the increase of contrast with optical density. Since the contrast/noise ratio also increases (with the square root of optical
density), the perception of indications of small flaws improves significantly with higher optical density. The operator should mask all film areas of lower
optical density to avoid blinding (dazzling). Blinding reduces the eye perception and requires longer eye adaptation time. High brightness viewing stations
also heat up films depending on the optical density and viewing time. The operator shall prevent overheating to protect the film integrity.
FIG. 1 Maximum Allowable Optical Density with Film Viewer Output
E1742/E1742M − 23
luminance (see 6.27.4). The maximum readable optical density shall be demonstrated on an exposure of a like section in which
shall always be posted on the viewer. the required IQI shall be placed on the source side, and sets of
wire IQIs, (or a series of hole-type IQIs) ranging in thickness
6.11 Processing Radiographs—Radiographs shall be free
from that of the required IQI to one fourth that thickness shall
from blemishes which may interfere with radiographic inter-
be placed on the film side. If the required IQI on the source side
pretation.
indicates the specified radiographic quality level, then the
6.12 IQI Selection—The IQI thickness shall be based on a
image of either the smallest IQI hole in the thinnest IQI, or the
thickness not greater than the nominal thickness to be radio-
image of the smallest wire, visible on the film side, shall be
graphed. For double-wall exposures and double-wall viewing
used to determine the proper film-side IQI to be used for
techniques, the IQI shall be based on the double-wall thickness
production radiographs.
of the component. The IQI thicknesses that are in between, or
6.13.2.2 Film-Side IQIs (Double Wall-Single Image)—
smaller than, the thickness increments in Fig. A1.1 (for
When performing double-wall radiography in which only the
example, a hole-type IQI that is 0.0025 in. or 0.006 in. thick)
wall portion next to the film is viewed for acceptance, the
may be used but are not mandatory. For double-wall exposures
film-side radiographic technique shall be demonstrated on an
and single-wall viewing techniques, the IQI shall be based on
exposure of a like section in which the required IQI is placed
the single-wall thickness of the component. In no case shall the
on the inside of the part and a set of IQIs, as specified in
IQI thickness be based on a thickness greater than the thickness
6.13.2.1, are placed on the film side. If the IQI on the inside
to be radiographed. For fabrication welds the IQI shall be
indicates the required radiographic quality level, then the
selected in accordance with Annex A2. For explosive/
image of either the smallest IQI hole in the thinnest IQI, or the
propellants, rocket motors, and their components, IQI selection
image of the smallest wire, visible on the film side, shall be
shall be as specified in accordance with Annex A3.
used to determine the proper film-side IQI to be used for
production radiographs.
6.13 Placement of IQIs—An IQI shall be placed on each
part radiographed for the duration of exposure, unless a
6.13.3 IQI Qualification Exposure—When included in the
number of identical parts are simultaneously exposed on a
written procedure and approved by the Level III radiographer
single film. In such a case, a single IQI shall be placed upon the
of the cognizant engineering organization, a single exposure
source side of a part at the outer edge of the cone of radiation
with the applicable IQI may be made to qualify the examina-
or farthest extremity of the exposure setup (that is, farthest
tion process.
from the radiation beam centerline). For examination of
6.13.3.1 Qualification Exposure—When it is impractical to
irregular objects, the IQI shall be placed on the area of the part
continually place IQIs on a part requiring more than one
farthest from the film. The IQIs shall be placed adjacent to the
exposure, a single exposure of the IQI may be made to qualify
area of interest, since accept/reject decisions cannot be made in
the examination process. As long as the radiographic technique
the area directly beneath the IQI. Where it is not practicable to
is not changed, subsequent exposures may be performed
place the IQI on the part, the separate block technique in
without an IQI. A new qualification exposure with an IQI shall
6.13.1, or the film-side technique in 6.13.2, may be used as
be made daily, or whenever any of the following parameters
applicable.
are changed:
6.13.1 Shim, Separate Block, or Like-Section IQI
(1) Energy level (kilovolts or Megavolts),
Technique—Where it is impractical to place the IQI upon the
(2) Exposure (milliampere × time),
part radiographed, the IQI may be placed on the source side of
(3) Source-to-film distance,
a separate shim, block, or like section, from the same material
(4) Screens, collimation, masking, or filters,
group (or material that is radiographically similar or of a lower
(5) Film type, or
radiographic attenuation, see 5.5.2) as either the IQI or the part.
(6) Film processing parameters.
The shim, block, or like section and IQI shall be placed on the
6.13.3.2 Subsequent Exposures—Subsequent exposures
outer edge of the cone of radiation. The shim, block, or like
shall be positively tied to the qualification exposure by
section shall exceed the IQI dimensions so that at least three
serialization or other methods. A copy of the qualification shall
sides of the IQI shall be visible on the radiograph. If required
be provided to all parties with review authority.
by the CEO, the shim shall be placed on a low-absorptive
6.13.4 Re-Radiography—Whenever there is a reasonable
material (such as polystyrene plastic or its equivalent) to ensure
doubt as to the interpretation or clarity of the radiograph
that the IQI shall not be any closer to the film than the source
because of film artifacts or improper technique, re-radiography
side of the part, or area of interest being evaluated.
is required.
6.13.2 Film-Side IQI Placement—When examining double-
walled parts such as tubing or hollow castings, and it is not
6.14 Masking—Shot, masking solutions, sheet lead and
practical to place an IQI on the source side of the part, IQIs
foils, polytetrafluoroethylene (PTFE), plastic, or other nonme-
may be placed on the film side of the part as specified in
tallic absorbers may be used as masking to minimize the effects
6.13.2.1 and 6.13.2.2. A letter “F” shall be placed adjacent to
of scattered radiation or undercutting. The shot may be a
the IQI.
mixture of many diameters to provide a uniform optical
6.13.2.1 Film-Side IQIs (Double Wall-Double Image)— density. Heavy chemical solutions used for masking may be
When performing double-wall radiography in which both walls toxic; the proper health and safety precautions and markings
are viewed for acceptance, the film-side radiographic technique shall be used.
E1742/E1742M − 23
6.15 Filters—Filters may be used whenever the contrast 6.18.4 When surfaces are inaccessible an alternate method
reductions caused by low-energy scattered radiation occurring of qualification shall be used subject to the approval of the
on production radiographs are of significant magnitude to cognizant engineering organization.
cause difficulty in meeting the radiographic quality level or
6.19 Fabrication Welds—Fabrication welds shall be pro-
radiographic coverage requirements as specified in the
cessed in accordance with Annex A2.
contract, purchase order, or drawing.
6.20 IQI Selection for Explosives/Propellants, Rocket
6.16 Multiple-Film-Cassette Exposure—Where more than
Motors, and Their Components—These devices shall be radio-
one film cassette is used to cover the area of interest in a single
graphed in accordance with Annex A3.
exposure, an IQI image shall appear on at least one radiograph
6.20.1 Single-Wire IQIs—Single-wire IQIs of a (metallic)
at the edge of the film most distant from the center of the
material with higher mass attenuation coefficient may be used,
radiation beam. When the source is placed on the axis of the
provided the thickness of metal upon which the IQI is based
object, and the complete circumference is radiographed with a
has been equated to the equivalent explosive/propellant thick-
single exposure, at least three equally spaced IQIs are to be
ness. Wire thickness shall be equated to hole-type radiographic
used if possible.
quality levels (as specified in Table 3) by the following
6.17 Applicable IQI Area of Interest—(a) One IQI shall
method:
represent an area within which optical densities do not vary
Wire IQI diameter 5 TPY/XF (1)
more than +30 % to −15 % from the optical density measured
where:
through the body of the IQI. (b) When shims are used with
hole-type IQIs, the +30 % optical density restriction of letter
T = total equivalent thickness, or thickness of explosive/
(a) above may be exceeded, as long as the required IQI
propellant material,
sensitivity and optical density requirements of the CEO are met P = required sensitivity as a percentage of material thickness
(see Note 4). (c) At least one IQI per radiograph shall be used, (that is, equivalent IQI sensitivity),
Y = material density of explosive/propellant,
except as specified in 6.16, 6.17.1, and 6.18. Accept/reject
X = material density of IQI material, and
decisions shall not be made directly beneath the IQI shim
F = form factor for round wire (0.7854).
combination.
6.21 Contrast—The contrast of the radiograph shall be
NOTE 4—Letter (b) applies to welds where the IQI is placed on the part;
determined by measuring the difference in optical density of
(b) does not apply to welds when blocks are used.
the film through the IQI and the adjacent material. The
6.17.1 Radiograph Qualification Using Two IQIs—When
minimum optical density difference shown in Fig. 2 shall be
the optical density varies by more than is specified in 6.17, two
achieved between the IQI and the base metals for Radiographic
IQIs used in the following manner are acceptable. If one IQI
Quality Levels 1 and 2.
shows an acceptable sensitivity in the most optically dense
portion of the radiograph, and the second IQI shows an
6.22 Back Scatter Radiation—During each exposure the
acceptable sensitivity in the least optically dense portion of the
film shall be monitored for back scatter. Each film holder shall
radiograph, the two IQIs shall serve to qualify the radiograph have a lead letter “B” a minimum of 0.5 in. (12.7 mm) high and
within these optical density limits plus the +30 % ⁄–15 % of
a minimum of 0.0625 in. (1.6 mm) thick positioned behind the
6.17. Additional IQIs may be used, as necessary in subsequent film and within the general area of the film to be viewed.
exposures, to cover the entire thickness range of the object. For
Should the image of the lead letter “B” appear on the
components such as castings and forgings, where there are
radiograph as a light image, the radiograph shall be considered
changes in wall thickness and wall alignment and the use of
unacceptable and screens, lead backing, or other appropriate
two IQIs is not possible, the use of one IQI is acceptable. The
measures shall be implemented on subsequent exposures to
IQI thickness shall be based on the thinnest wall being
reduce back scatter. The appearance of a dark image (higher
radiographed and shall be placed on the thickest wall section.
optical density “B” image) should be disregarded unless the
The required +30 % to −15 % optical density tolerance (see
dark image could be confused with, or interfere with, interpre-
6.17), need not be met; however, the optical density in the areas
tation in the area of interest. When identical parts, or segments
of interest shall be between 1.5 and 4.0 (and up to 4.5 by
of parts, are to be examined by the same technique, the letter
agreement of CEO; see Note 1 of Fig. 1) and the required
“B” may be used to qualify the initial exposure only and may
radiographic quality level shall be obtained.
be omitted for subsequent exposures as long as the proximity
and nature of backscattering objects and similar conditions are
6.18 Non-Requirement of IQIs—The IQIs are not required
maintained constant. A new qualification exposure shall be
when:
made whenever any of the following parameters are changed:
6.18.1 Examining assemblies for debris,
6.22.1 X-ray machine voltage (kilovolts, Megavolts, or
6.18.2 Conducting radiography for defect removal provided
gamma source type),
final examination of the area includes an IQI,
6.22.2 Exposure time (milliampere-time),
6.18.3 Examining to show material details or contrast be-
6.22.3 Source-to-film distance,
tween two or more dissimilar materi
...

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. Because
it 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 version
of the standard as published by ASTM is to be considered the official document.
Designation: E1742/E1742M − 18 E1742/E1742M − 23
Standard Practice for
Radiographic Examination
This standard is issued under the fixed designation E1742/E1742M; 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.
This standard has been approved for use by agencies of the U.S. Department of Defense.
1. Scope*
1.1 This practice establishescovers the minimum requirements for radiographic examination for metallic and nonmetallic
materials.
1.2 Applicability—The criteria for the radiographic examination in this practice are applicable to all types of metallic and
nonmetallic materials. When specified, it may be used for radiographic inspection of metallic or non-metallic materials, weldments,
castings, and brazed materials. The requirements expressed in this practice are intended to control the quality of the radiographic
images and are not intended to establish acceptance criteria for parts and materials.
1.3 Basis of Application—There are areas in this practice that may require agreement between the cognizant engineering
organization and the supplier, or specific direction from the cognizant engineering organization. These items should be addressed
in the purchase order or the contract.
1.3.1 DoD contracts.
1.3.2 Personnel qualification, 5.1.1.
1.3.3 Agency qualification, 5.1.2.
1.3.4 Digitizing techniques, 5.4.5.
1.3.5 Alternate image quality indicator (IQI) types, 5.5.3.
1.3.6 Examination sequence, 6.6.
1.3.7 Non-film techniques, 6.7.
1.3.8 Radiographic quality levels, 6.9.
1.3.9 Optical density, 6.10.
This practice is under the jurisdiction of ASTM Committee E07 on Nondestructive Testing and is the direct responsibility of Subcommittee E07.01 on Radiology (X and
Gamma) Method.
Current edition approved March 1, 2018Dec. 15, 2023. Published March 2018January 2024. Originally approved in 1995. Last previous edition approved in 20122018
as E1742/E1742M – 12.E1742/E1742M – 18. DOI: 10.1520/E1742_E1742M-18.10.1520/E1742_E1742M-23.
This practice replaced MIL-STD-453.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
E1742/E1742M − 23
1.3.10 IQI qualification exposure, 6.13.3.
1.3.11 Non-requirement for IQI, 6.18.
1.3.12 Examination coverage for welds, A2.2.2.
1.3.13 Electron beam welds, A2.3.
1.3.14 Geometric unsharpness, 6.23.
1.3.15 Responsibility for examination, 6.27.1.
1.3.16 Examination report, 6.27.2.
1.3.17 Retention of radiographs, 6.27.8.
1.3.18 Storage of radiographs, 6.27.9.
1.3.19 Reproduction of radiographs, 6.27.10 and 6.27.10.1.
1.3.20 Acceptable parts, 6.28.1.
1.4 Units—The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in
each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from
the two systems may result in non-conformance with 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 responsibility
of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of
regulatory limitations prior to use.
1.6 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.
2. Referenced Documents
2.1 The following documents form a part of this practice to the extent specified herein:
2.2 ASTM Standards:
E94E94/E94M Guide for Radiographic Examination Using Industrial Radiographic Film
E543 Specification for Agencies Performing Nondestructive Testing
E747 Practice for Design, Manufacture and Material Grouping Classification of Wire Image Quality Indicators (IQI) Used for
Radiology
E801 Practice for Controlling Quality of Radiographic Examination of Electronic Devices
E999 Guide for Controlling the Quality of Industrial Radiographic Film Processing
E1025 Practice for Design, Manufacture, and Material Grouping Classification of Hole-Type Image Quality Indicators (IQI)
Used for Radiography
E1030E1030/E1030M Practice for Radiographic Examination of Metallic Castings
E1032 Practice for Radiographic Examination of Weldments Using Industrial X-Ray Film
E1079 Practice for Calibration of Transmission Densitometers
E1165 Test Method for Measurement of Focal Spots of Industrial X-Ray Tubes by Pinhole Imaging
E1254 Guide for Storage of Radiographs and Unexposed Industrial Radiographic Films
E1255 Practice for Radioscopy
E1316 Terminology for Nondestructive Examinations
E1390 Specification for Illuminators Used for Viewing Industrial Radiographs
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
E1742/E1742M − 23
E1411 Practice for Qualification of Radioscopic Systems
E1416 Practice for Radioscopic Examination of Weldments
E1815 Test Method for Classification of Film Systems for Industrial Radiography
E2033 Practice for Radiographic Examination Using Computed Radiography (Photostimulable Luminescence Method)
E2698 Practice for Radiographic Examination Using Digital Detector Arrays
2.3 AWS Document:
AWS A2.4 Standard Symbols for Welding, Brazing, and Nondestructive Examination
2.4 Aerospace Industries Association Document:
NAS 410 Certification & Qualification of Nondestructive Test Personnel (Replacement for MIL-STD-410 Nondestructive
Testing Personnel Qualification and Certification)
2.5 ASNT Documents:
SNT-TC-1A Recommended Practice for Personnel Qualification and Certification in Nondestructive Testing
ANSI/ASNT-CP-189 ASNT Standard for Qualification and Certification of Nondestructive Testing Personnel
2.4 NCRP Documents:
NCRP 116 Limitation of Exposure to Ionizing Radiation
NCRP 144 Radiation Protection for Particle Accelerator Facilities
NCRP 147 Structural Shielding Design for Medical X-ray Imaging Facilities
2.5 ANSI/ISO Standards:
ANSI/NCSL Z540-3 Requirements for the Calibration of Measuring and Test Equipment
ISO 10012 Measurement Management Systems—Requirements for Measurement Processes and Measuring Equipment
ISO 5579 Non-Destructive Testing-Radiographic Examination of Metallic Materials by X-and Gamma-Rays-Basic Rules
ISO 9712 NDT—Qualification and Certification of NDT Personnel
NOTE 1—DoD Contracts: Unless otherwise specified, the issues of the documents that are DoD adopted are those listed in the issue of the DoDISS
(Department of Defense Index of Specifications and Standards) cited in the solicitation.
NOTE 2—Order of Precedence: In the event of conflict between the text of this practice and the references cited herein, the text of this practice takes
precedence. Nothing in this practice, however, supersedes applicable laws and regulations unless a specific exemption has been obtained.
3. Terminology
3.1 Definitions—Definitions relating to radiographic examination, which appear in Terminology E1316, shall apply to the terms
used in this practice.
3.1.1 Optical density is the correct term for assessing the developed film obtained from a penetrating radiation film inspection.
Historically, the terms film or radiographic density, or both, have been used to describe the measurements taken from viewing the
images, but the current definition of film density, in Terminology E1316, is “the quantitative measure of diffuse optical light
transmission (optical density, blackening) through a developed film.” In addition, with the advent of digital radiography, these
historical terms may cause confusion to those utilizing more than the film technique. For standards purposes, the correct term is
optical density and has been replaced throughout this standard.
3.2 Definitions of Terms Specific to This Standard:
3.2.1 cognizant engineering organization—the company, government agency, or other authority responsible for the design, or end
use, of the system or component for which radiographic examination is required. This, in addition to design personnel, may include
personnel from engineering, material and process engineering, stress analysis, NDT, or quality groups and others, as appropriate.
3.2.1 component—component, n—the part(s) or element of a system, assembled or processed to the extent specified by the
drawing, purchase order, or contract.
3.2.2 energy—energy, n—a property of radiation that determines its penetrating ability. In X-ray radiography, energy machine
rating is determined by kilovolts (keV), million electronvolts (MeV). In gamma ray radiography, energy is a characteristic of the
source used.
3.2.3 like section—section, n—a separate section of material that is similar in shape and cross section to the component or part
being radiographed, and is made of the same or radiographically similar material.
Available from American Welding Society (AWS), 550 NW LeJeune Rd., Miami, FL 33126, http://www.aws.org.
Available from National Council on Radiation Protection and Measurements, NCRP Publications, 7910 Woodmount Ave., Suite 800, Bethesda, MD 20814.
Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http://www.ansi.org.
E1742/E1742M − 23
3.2.4 material group—group, n—materials that have the same predominant alloying elements and which can be examined using
the same IQI. A listing of common material groups is given in Practice E1025.
3.2.5 NDT facility—facility, n—the NDT facility performing the radiographic examination.
3.2.6 radiographic quality level—level, n—Thethe ability of a radiographic procedure to demonstrate a certain IQI sensitivity.
4. Significance and Use
4.1 This practice establishes the basic parameters for the application and control of the radiographic method. This practice is
written so it can be specified on the engineering drawing, specification, or contract. It is not a detailed how-to procedure to be used
by the NDT facility and, therefore, must be supplemented by a detailed procedure (see 6.1). Test Methods Practices
E1030E1030/E1030M, E1032, and E1416 contain information to help develop detailed technique/procedure requirements.
5. General Practice
5.1 Qualification:
5.1.1 Personnel Qualification—Personnel performing examinations in accordance with If specified in the contractual agreement,
personnel performing examinations to this practice shall be qualified in accordance with NAS 410, ANSI/ASNT-CP-189,
SNT-TC-1A, or ISO 9712 a nationally or internationally recognized NDT personnel qualification practice or standard and certified
by the employer or certifying agency as applicable. Other equivalent qualification documents may be used when specified in the
contract or purchase order.agency, as applicable. The practice or standard used shall be identified in the contractual agreement
between the using parties.
5.1.2 Agency Evaluation—If specified in the contractual agreement, NDT agencies shall be qualified and evaluated in accordance
with Specification E543. The applicable revision of Specification E543 shall be specified in the contractual agreement.
5.2 Laboratory Installations:
5.2.1 Safety—The premises and equipment shall present no hazards to the safety of personnel or property. NCRP 147, NCRP 116,
and NCRP 144 may be used as guides to ensure that radiographic procedures are performed so that personnel shall not receive a
radiation dosage exceeding the maximum permitted by city, state, or national codes.
5.2.2 Radiographic Exposure Areas—Radiographic exposure areas shall be clean and equipped so that acceptable radiographs may
be produced in accordance with the requirements of this practice.
5.2.3 Darkroom—Darkroom facilities, including equipment and materials, shall be capable of producing uniform radiographs free
of blemishes or artifacts, which might interfere with interpretation in the area of interest.
5.2.4 Film Viewing Area—The film viewing room or enclosure shall be an area with subdued lighting to preclude objectionable
reflective glare from the surface of the filmradiograph under examination (see 6.27.6).
5.3 Materials:
5.3.1 Film—Film selection for production radiographs should be based on radiation source energy level, part thickness/
configuration, and image quality. Only film systems having cognizant engineering organization approval or meeting the class
requirements of Test Method E1815 shall be used.
5.3.1.1 Nonfilm Recording Media—Other recording media, such as paper and analog tape, media may be used when approved by
the cognizant engineering organization.
5.3.2 Film Processing Solutions—Production radiographs shall be processed in solutions capable of consistently producing
radiographs that meet the requirements of this practice. Solution control shall be in accordance with Annex A4. Guide E999 should
be consulted for guidance on film processing.
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5.4 Equipment:
5.4.1 Radiation Sources:
5.4.1.1 X-Radiation Sources—Selection of appropriate X-ray voltage and current levels is dependent upon variables regarding the
specimen being examined (material type and thickness) and exposure time. The suitability of these exposure parameters shall be
demonstrated by attainment of the required radiographic quality level and compliance with all other requirements stipulated herein.
5.4.1.2 Gamma Radiation Sources—Isotope sources that are used shall be capable of demonstrating the required radiographic
quality level.
5.4.2 Film Holders and Cassettes—Film holders and cassettes shall be light tight, constructed of materials that do not interfere
with the quality or sensitivity of radiographs, and shall be handled properly to reduce damage. In the event that light leaks into
the film holder and produces images on the radiograph, the radiograph need not be rejected unless the images obscure, or interfere
with, the area of interest. If the film holder exhibits light leaks it shall be further repaired before use, or discarded. Film holders
and cassettes should be routinely examined for cracks or other defects to minimize the likelihood of light leaks.
5.4.3 Intensifying Screens:
5.4.3.1 Lead Foil Screens—When using a source greater than 150 keV, intensifying screens of the lead foil type are recommended.
Screens shall have the same area dimensions as the film being used and shall be in intimate contact with the film during exposure.
Recommended screen thicknesses are listed in Table 1 for the applicable voltage range being used. Screens shall be free from any
cracks, creases, scratches, or foreign material that could render undesirable nonrelevant images on the film.radiograph.
5.4.3.2 Fluorescent, Fluorometallic, or Other Metallic Screens—Fluorescent, fluorometallic, or other metallic screens may be
A
TABLE 1 Lead Screen Thickness
Energy Range/ Front Screen Back Screen Front and
B
Isotopes Minimum Back Screens
in. in. mm
C D
0 – 150 keV 0.000 to 0.001 0.005 0–0.15
C D
0 keV – 150 keV 0.000 to 0.001 0.005 0–0.15
D
151 – 200 keV 0.000 to 0.005 0.005 0.02–0.15
D
151 keV – 200 keV 0.000 to 0.005 0.005 0.02–0.15
201 – 320 keV 0.001 to 0.010 0.005 0.02–0.2
201 keV – 320 keV 0.001 to 0.010 0.005 0.02–0.2
Se-75 0.001 to 0.010 0.005 0.1–0.2
321 – 450 keV 0.005 to 0.015 0.01 0.1–0.2
321 keV – 450 keV 0.005 to 0.015 0.01 0.1–0.2
Ir-192 0.005 to 0.015 0.01 0.02–0.2
451 keV – 2 MeV 0.005 to 0.020 0.01 0.1–0.5
451 keV – 2 MeV 0.005 to 0.020 0.01 0.1–0.5
Co-60 0.005 to 0.020 0.01 0.1–0.5
2 – 4 MeV 0.010 to 0.020 0.01 0.1–0.5
2 MeV – 4 MeV 0.010 to 0.020 0.01 0.1–0.5
4 – 10 MeV 0.010 to 0.030 0.01 0.5–1.0
4 MeV – 10 MeV 0.010 to 0.030 0.01 0.5–1.0
10 – 25 MeV 0.010 to 0.050 0.01 1.0–2.0
10 MeV – 25 MeV 0.010 to 0.050 0.01 1.0–2.0
A
The lead screen thickness listed for the various energy ranges are recom-
mended thicknesses and not required thicknesses. Other thicknesses and mate-
rials may be used provided the required radiographic quality level, contrast, and
optical density are achieved.
B
Lead Lead screen thicknesses in accordance with EN 444 and ISO 5579 in SI
units. For energy ranges of Co-60 and 451 keV to 4 MeV, steel or copper screens
of 0.1 to 0.5 mm 0.1 mm to 0.5 mm may be used. For energy ranges above 4 MeV
to 10 MeV, 0.5-1.0 mm 0.5 mm to 1.0 mm steel or copper or up to 0.5 mm 0.5 mm
tantalum screens are recommended. Additional back scatter shielding may be
achieved by additional lead screens behind the cassettes.
C
Prepackaged film with lead screens may be used from 8080 keV to 150 keV. No
lead screens are recommended below 80 keV. 80 keV. Prepackaged film may be
used at higher energy levels provided the contrast, optical density, radiographic
quality level, and backscatter requirements are achieved. Additional intermediate
lead screens may be used for reduction of scattered radiation at higher energies.
D
No back screen is required provided the backscatter requirements of 6.22 are
met.
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used. However, they must be capable of demonstrating the required penetrameter (IQI) sensitivity. Fluorescent or fluorometallic
screens may cause limitations in image quality (see Guide E94E94/E94M, Appendix X1).
5.4.4 Film Viewers—Viewers used for final interpretation shall meet the following requirements:
5.4.4.1 The viewer shall contain a variable control to allow the selection of optimum intensities for filmradiographs with varying
optical densities.
5.4.4.2 The light source shall have sufficient intensity to enable viewing of optical densities in the area of interest (see 6.27.4).
5.4.4.3 The light enclosure shall be designed to provide a uniform brightness level over the entire viewing screen.
5.4.4.4 The viewer shall be equipped with a suitable fan, blower, or other means to provide stable temperature at the viewing port
to avoid damaging the radiographic film while viewing.
5.4.4.5 The viewer shall be equipped with a translucent material front in each viewing port, except for localized high-intensity
viewing of high-optical-density filmradiographs areas through separate viewing ports, apertures, or other suitable openings.
5.4.4.6 A set of opaque masks, an iris-type aperture, or any other method to reduce the viewing area to suit the size of the area
of interest shall be provided.
5.4.4.7 Illuminators procured to, or meeting the requirements of, Specification E1390 are acceptable for use.
5.4.5 Digitizing Techniques—The use of film digitizing techniques is acceptable when approved by the cognizant engineering
organization.
5.4.6 Densitometers—The densitometer shall be capable of measuring the light transmitted through a radiograph with an optical
density up to 4.0 with a unit resolution of 0.02. When optical densities greater than 4.0 are permitted, a densitometer capable of
measuring optical densities up to the maximum optical density permitted is required.
5.4.7 Film Viewing Aids—Magnifiers shall be available to provide magnification between 3× and 10× to aid in interpretation and
determine indication size, as applicable. The specific magnifier used should be determined by the interpretation requirements.
Devices used for determining defect size shall be calibrated as scheduled in Table 2.
5.4.8 Luminance/illuminance light meters are procured and calibrated in accordance with Table 2.
5.5 Image Quality Indicators (IQIs):
5.5.1 Image Quality Indicators (IQIs)—The IQIs shall be in accordance with contract requirements. Hole-type IQIs in accordance
with this practice, Practice E1025, or the alternate design of Annex A1, or wire-type IQIs in accordance with Practice E747, shall
be used when IQIs are required. If wire IQIs are used, they shall be correlated to hole-type radiographic quality levels in
accordance with Practice E747. For the radiography of electronic devices, Practice E801 shall be used.
5.5.2 Radiographically Similar IQI Material—Materials shall be considered radiographically similar if the following requirements
are satisfied. Two blocks of equal thickness, one of the material to be radiographed and one of the material of which the IQIs are
made, shall be exposed together on the same film at the lowest energy level to be used for production radiographs. If the optical
density of the material to be radiographed is within the range from 0 to +15 % of the IQI material (that is, the IQI is slightly more
attenuating), the IQI material shall be considered radiographically similar and may be used to fabricate IQIs for examination of
the production material. The optical density readings shall be between 2.0 and 4.0 for both materials. An IQI with a lower radiation
attenuation may be used.
5.5.3 Alternate IQI Types—The use of other types of IQIs, or modifications to types specified in 5.5.1, is permitted upon approval
of the cognizant engineering organization. Details of the design, materials designation, and thickness identification of the IQIs shall
be in the written procedure, or documented on a drawing that shall be referenced in the written procedure (see 6.1).
5.5.4 IQI Control—The IQIs shall be procured or fabricated to the requirements of Practice of E1025, or the alternate design of
Annex A1, as applicable, with a manufacturer’s certification of compliance with respect to alloy and dimensions. Users shall
visually inspect IQIs for damage, chamfering, and cleanliness in accordance with Table 2.
E1742/E1742M − 23
TABLE 2 Process Control Checks
Check Frequency Paragraph
A,B
Discontinuity Image Measuring 5.4.7
Device
Image Quality Indicators:
Certified When procured 5.5.4
C
Check (Condition) prior to use 5.5.4
Automatic Processing:
D
Processor Performance Daily A4.2.1
D
Base Fog Daily A4.2.5
C
Developer Temperature Prior to use A4.2.3
E
Replenishment Rate A4.2.2
F
Transport Speed A4.2.4
Manual Processing:
Processing Performance Daily A4.3.1
Base plus Fog Monthly A4.2.5
G
Developer Temperature Prior to use A4.3.2
Densitometer:
H
Verification Check Each shift 6.27.5
I
Calibration Check 3 months 6.27.5
Light Meters Annual 6.27.4/6.27.6
Viewer Light Intensity 6.27.4
B
Thermometer Calibration 6 months A4.2.3
J
Ambient Visible Light 6 months 6.27.6
Stepwedge Calibration Annual 6.27.5
A
Optical Devices—When procured; mechanical devices (see Footnote B).
B
Calibrated and recorded in accordance with ANSI Z540-3, or ISO 10012, as
applicable.
C
Documentation of this check not required.
D
May be extended to weekly when substantiated by actual technical/reliability
data and approved by the cognizant engineering organization.
E
Measured and recorded when solutions are changed during preventative
maintenance or repair.
F
Measured and recorded during preventative maintenance or repair.
G
Temperatures shall be checked prior to each use. Daily documentation of this
check is required.
H
Each shift or when maintenance is performed (bulb or aperture changed).
I
Every three months or whenever the densitometer verification check is not within
tolerance.
J
Fixed viewing locations with acceptable and controlled ambient lighting condi-
tions need not be re-verified as long as those conditions are maintained.
6. Detail Requirements
6.1 Written Procedure—It shall be the responsibility of the NDT facility to develop a workable examination technique recorded
as a written procedure that is capable of consistently producing the desired results and radiographic quality level. When required
by contract or purchase order, the procedure shall be submitted to the cognizant engineering organization for approval. The written
procedure shall contain, as a minimum, the following information:
6.1.1 A drawing, sketch, or photograph of the component showing the location of the film and IQI with respect to the radiation
source for each exposure.
6.1.2 The angle of the radiation beam in relation to the component, the source-to-film distance, and any blocking or masking, if
used.
6.1.3 Part zones, if applicable, should be included (see 6.2). This may be accomplished through drawings and tables or by
reference to documents where such information is found.
6.1.4 The nominal exposure for X-ray machines, the voltage, milliamps, time (or rads as applicable), and effective focal spot size.
For radioisotope sources, the isotope type, source strength (curies), exposure time, and source size.
6.1.5 Film designation (for example, brand, type, and processing parameters), intensifying screens (for example, type and
thickness of screens), or filters (for example, filter material, thickness, and location) if used, film loading instructions (for example,
when using multiple film exposure techniques), and the desired optical density range.
E1742/E1742M − 23
6.1.6 Thickness and type of material.
6.1.7 The IQI size and type, and the required radiographic quality level. If alternate IQIs are used (see 5.5.3), include details of
the design or reference to documents where such information is found.
6.1.8 Thickness and type of material for shims or blocks, or both, if used.
6.1.9 Name and address of the NDT facility and the date, or revision, of the procedure.
6.1.10 Radiographic identification scheme used to correlate part-to-film. If the examination procedures are similar for many
components, a master written procedure may be used that covers the details common to a variety of components. All written
procedures shall be approved by an individual qualified and certified as a Level III for radiography in accordance with 5.1.1.
6.2 Acceptance Requirements—When examination is performed in accordance with this practice, engineering drawings,
specifications, or other applicable documents shall indicate the criteria by which the components are judged acceptable. Complex
components may be divided into zones and separate criteria assigned to each zone in accordance with its design requirements.
When used, direct references to ASTM reference radiographic standards shall include the grade level for each type of discontinuity
permitted for each part or zone.
NOTE 3—Information on reference radiographs can be obtained from the Annual Book of ASTM Standards, Vol 03.03 or from ASTM Headquarters.
6.3 Surface Preparation—Components may be examined without surface preparation or conditioning except as required to remove
surface conditions that may interfere with proper interpretation of radiographs.
6.3.1 Castings, forgings, and weldments may be radiographed in the as-cast, as-forged, or as-welded conditions provided the
following requirements are met.
6.3.1.1 For castings and forgings, the surface condition shall not interfere with evaluation.
6.3.1.2 Accessible surfaces of welds shall be prepared in accordance with A2.1.
6.4 Radiographic Identification—Each radiograph shall carry the identification or serial number of the component and view
number, when multiple views are taken. Each radiograph shall also carry the identification of the NDT facility examining the
component and the date of the examination. Radiographs of a repair area shall be identified with R1, R2, R3, and so forth, indicating
the number of times that repairs were attempted. Alternative schemes may be used for identification of repair radiographs so long
as each film is clearly identified to relate to a particular repair area. For explosives and propellants, the conditioning temperature
shall be identified on each X-ray film if the ordnance has been conditioned to a temperature other than facility ambient for purposes
of examination.
6.5 Examination and Coverage—The number of parts examined, and the radiographic coverage of each part shall be as specified
by drawings, radiographic techniques, radiographic manuals, handbooks for aircraft technical orders, or other specifications, as
applicable. Areas to be examined shall be identified on the drawing by using the symbols in accordance with AWS A2.4 or other
systems of designations that are easily identified on the drawing. If the number of parts to be examined and the amount of coverage
of each part is not specified, all parts shall be examined and shall receive 100 % radiographic coverage.
6.6 Examination Sequence—The sequence for radiographic examination in the production operation should be specified in the
manufacturing or assembly process specification, contract, or purchase order. If not specified, radiographic examination shall be
performed at a stage in the process of manufacturing or assembly at which discontinuities can be detected. Radiographic
examination may be performed before heat treatment, provided liquid penetrant or magnetic particle examinations are performed
after heat treatment.
6.7 Nonfilm Techniques—When permitted by purchase order, contract, or specification, radioscopic/radiological examinations
using nonfilm techniques shall be in accordance with Practices E1255, E2033 or E2698 or a nonfilm specification approved by the
Cognizant Engineering Organization (CEO) cognizant engineering organization as required. Prior approval shall be obtained from
the Level III radiographer of the cognizant engineering organization (see 5.1.1).
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6.8 Multi-Film Techniques—Film techniques with two or more films of the same or different speeds in the same film holder, to
be used in either single or superimposed film viewing, shall be permitted provided that the applicable radiographic quality level,
and optical density requirements (see 6.9 and 6.10), are achieved for the area of interest.
6.9 Radiographic Quality Levels—The five quality levels listed in Table 3 may be assigned on the basis of IQI thickness and the
perceptibility of one, two, or three holes in the hole-type IQI image on the radiograph. If the quality level is not specified on the
drawing or other applicable documents, it shall be Level 2-2T. Unless otherwise specified by the cognizant engineering
organization, hole-type IQIs used for examination of material 0.25 in. (6.35 mm)[6.35 mm] or less in thickness shall be 0.005-in.
(0.127-mm)0.005 in. [0.127 mm] minimum thickness.
6.10 Optical Density—For single-film viewing, the optical density shall be ≥1.5 in the area of interest. Where superimposed
filmradiograph viewing is used, the optical density of the superimposed filmsradiographs shall be from 2.0 in the area of interest,
and each individual filmradiograph shall not have an optical density below 1.0 in the area of interest. Optical densities above 4.0
are permitted when agreed upon between the cognizant engineering organization and the NDT facility (see Note 1 of Fig. 1). In
no case shall the maximum optical density exceed 4.5. For single-film viewing, optical densities less than 1.5 are permitted only
when items not requiring an IQI (see 6.18) are examined. The maximum readable optical density depends on the film viewer used
and its maximum luminance (see 6.27.4). The maximum readable optical density shall always be posted on the viewer.
6.11 Processing Radiographs—Radiographs shall be free from blemishes which may interfere with filmradiographic interpreta-
tion.
6.12 IQI Selection—The IQI thickness shall be based on a thickness not greater than the nominal thickness to be radiographed.
For double-wall exposures and double-wall viewing techniques, the IQI shall be based on the double-wall thickness of the
component. The IQI thicknesses that are in between, or smaller than, the thickness increments in Fig. A1.1 (for example, a
hole-type IQI that is 0.00250.0025 in. or 0.006 in. thick) may be used but are not mandatory. For double-wall exposures and
single-wall viewing techniques, the IQI shall be based on the single-wall thickness of the component. In no case shall the IQI
thickness be based on a thickness greater than the thickness to be radiographed. For fabrication welds the IQI shall be selected in
accordance with Annex A2. For explosive/propellants, rocket motors, and their components, IQI selection shall be as specified in
accordance with Annex A3.
6.13 Placement of IQIs—An IQI shall be placed on each part radiographed for the duration of exposure, unless a number of
identical parts are simultaneously exposed on a single film. In such a case, a single IQI shall be placed upon the source side of
a part at the outer edge of the cone of radiation or farthest extremity of the exposure setup (that is, farthest from the radiation beam
centerline). For examination of irregular objects, the IQI shall be placed on the area of the part farthest from the film. The IQIs
shall be placed adjacent to the area of interest, since accept/reject decisions cannot be made in the area directly beneath the IQI.
6.13.1, or the film-side technique in 6.13.2,
Where it is not practicable to place the IQI on the part, the separate block technique in
may be used as applicable.
6.13.1 Shim, Separate Block, or Like-Section IQI Technique—Where it is impractical to place the IQI upon the part radiographed,
the IQI may be placed on the source side of a separate shim, block, or like section, from the same material group (or material that
is radiographically similar or of a lower radiographic attenuation, see 5.5.2) as either the IQI or the part. The shim, block, or like
section and IQI shall be placed on the outer edge of the cone of radiation. The shim, block, or like section shall exceed the IQI
dimensions so that at least three sides of the IQI shall be visible on the radiograph. If required by the CEO, the shim shall be placed
TABLE 3 Quality Levels of Examination
Radiographic Maximum IQI Minimum Hole Equivalent IQI
IQI Designation
A B C
Quality Level Thickness, % Diameter Sensitivity, %
00 1–1T 1 1T 0.7
0 1–2T 1 2T 1.0
1 2–1T 2 1T 1.4
2 2–2T 2 2T 2.0
3 2–4T 2 4T 2.8
A
Expressed as a percentage of material thickness.
B
Expressed as multiple thickness of IQI.
C
Equivalent IQI sensitivity is that thickness of the IQI expressed as a percentage
of the specimen thickness in which a 2T hole would be clearly visible under the
same radiographic conditions.
E1742/E1742M − 23
NOTE 1—This figure is a depiction of the abscissa axis: Maximum Allowable Optical Density versus ordinate axis: Candela/m and footlamberts in
graphical format from tabular data derived from Specification E1390 and ISO 5580 (also known as EN 25580). Conversion from tabular data to a graph
accounts for the step in the line. For Film Viewer Output of 10 000 Candela/mcandela/m (2919 Footlamberts), the Maximum Allowable Optical Density
shall be 3.0. Regarding the ordinate axis: Candela/m , the minimum luminance level required for the average human eye to achieve photopic eye response
(that is where maximum resolution and contrast discrimination occurs) is at 10 candela/m . At levels below this value the eye responds scotopically which
means lower contrast discrimination and resolution. While photopic vision typically occurs at a threshold of 10 candela/m for the average human eye,
this curve takes advantage of the fact that at lower optical densities most viewers can achieve an amount of light that guarantees that virtually all operators
will be viewing film in the photopic vision mode, that is 30 candela/m for optical densities <2.5. A theoretical advantage of this curve is that it
compensates for the reduced contrast sensitivity of radiographic film at lower optical densities.
NOTE 2—NDT film systems, classified corresponding to Test Method E1815 system classes “Special, I and II,” with or without lead screens, are suitable
for the extended viewing range above an optical density of 4, due to their high gradient (G >6) at D = 4 above fog and base. These double sided
D-D0 = 4
NDT film systems have a high silver content and do not saturate as early as medical and classes III, W-A, W-B and W-C film systems. The basic advantage
of increasing the optical density is the increase of contrast with optical density. Since the contrast/noise ratio also increases (with the square root of optical
density), the perception of indications of small flaws improves significantly with higher optical density. The operator should mask all film areas of lower
optical density to avoid blinding (dazzling). Blinding reduces the eye perception and requires longer eye adaptation time. High brightness viewing stations
also heat up films depending on the optical density and viewing time. The operator shall prevent overheating to protect the film integrity.
FIG. 1 Maximum Allowable Optical Density with Film Viewer Output
on a low-absorptive material (such as polystyrene plastic or its equivalent) to ensure that the IQI shall not be any closer to the film
than the source side of the part, or area of interest being evaluated.
6.13.2 Film-Side IQI Placement—When examining double-walled parts such as tubing or hollow castings, and it is not practical
to place an IQI on the source side of the part, IQIs may be placed on the film side of the part as specified in 6.13.2.1 and 6.13.2.2.
A letter “F” shall be placed adjacent to the IQI.
6.13.2.1 Film-Side IQIs (Double Wall-Double Image)—When performing double-wall radiography in which both walls are viewed
for acceptance, the film-side radiographic technique shall be demonstrated on an exposure of a like section in which the required
IQI shall be placed on the source side, and sets of wire IQIs, (or a series of hole-type IQIs) ranging in thickness from that of the
required IQI to one fourth that thickness shall be placed on the film side. If the required IQI on the source side indicates the
specified radiographic quality level, then the image of either the smallest IQI hole in the thinnest IQI, or the image of the smallest
wire, visible on the film side, shall be used to determine the proper film-side IQI to be used for production radiographs.
E1742/E1742M − 23
6.13.2.2 Film-Side IQIs (Double Wall-Single Image)—When performing double-wall radiography in which only the wall portion
next to the film is viewed for acceptance, the film-side radiographic technique shall be demonstrated on an exposure of a like
section in which the required IQI is placed on the inside of the part and a set of IQIs, as specified in 6.13.2.1, are placed on the
film side. If the IQI on the inside indicates the required radiographic quality level, then the image of either the smallest IQI hole
in the thinnest IQI, or the image of the smallest wire, visible on the film side, shall be used to determine the proper film-side IQI
to be used for production radiographs.
6.13.3 IQI Qualification Exposure—When included in the written procedure and approved by the Level III radiographer of the
cognizant engineering organization, a single exposure with the applicable IQI may be made to qualify the examination process.
6.13.3.1 Qualification Exposure—When it is impractical to continually place IQIs on a part requiring more than one exposure, a
single exposure of the IQI may be made to qualify the examination process. As long as the radiographic technique is not changed,
subsequent exposures may be performed without an IQI. A new qualification exposure with an IQI shall be made daily, or
whenever any of the following parameters are changed:
(1) Energy level (kilovolts or Megavolts),
(2) Exposure (milliampere × time),
(3) Source-to-film distance,
(4) Screens, collimation, masking, or filters,
(5) Film type, or
(6) Film processing parameters.
6.13.3.2 Subsequent Exposures—Subsequent exposures shall be positively tied to the qualification exposure by serialization or
other methods. A copy of the qualification shall be provided to all parties with review authority.
6.13.4 Re-Radiography—Whenever there is a reasonable doubt as to the interpretation or clarity of the radiograph because of film
artifacts or improper technique, re-radiography is required.
6.14 Masking—Shot, masking solutions, sheet lead and foils, polytetrafluoroethylene (PTFE), plastic, or other low-optical-density,
nonmetallic absorbers may be used as masking to minimize the effects of scattered radiation or undercutting. The shot may be a
mixture of many diameters to provide a uniform optical density. Heavy chemical solutions used for masking may be toxic; the
proper health and safety precautions and markings shall be used.
6.15 Filters—Filters may be used whenever the contrast reductions caused by low-energy scattered radiation occurring on
production radiographs are of significant magnitude to cause difficulty in meeting the radiographic quality level or radiographic
coverage requirements as specified in the contract, purchase order, or drawing.
6.16 Multiple-Film-Cassette Exposure—Where more than one film cassette is used to cover the area of interest in a single
exposure, an IQI image shall appear on at least one radiograph at the edge of the film most distant from the center of the radiation
beam. When the source is placed on the axis of the object, and the complete circumference is radiographed with a single exposure,
at least three equally spaced IQIs are to be used if possible.
6.17 Applicable IQI Area of Interest—(a) One IQI shall represent an area within which optical densities do not vary more
than +30than +30 % to −15 % from the optical density measured through the body of the IQI. (b) When shims are used with
hole-type IQIs, the +30%+30 % optical density restriction of letter (a) above may be exceeded, as long as the required IQI
sensitivity and optical density requirements of the CEO are met (see Note 4). (c) At least one IQI per radiograph shall be used,
except as specified in 6.16, 6.17.1, and 6.18. Accept/reject decisions shall not be made directly beneath the IQI shim combination.
NOTE 4—Letter (b) applies to welds where the IQI is placed on the part; (b) does not apply to welds when blocks are used.
6.17.1 Radiograph Qualification Using Two IQIs—When the optical density varies by more than is specified in 6.17, two IQIs
used in the following manner are acceptable. If one IQI shows an acceptable sensitivity in the most optically dense portion of the
radiograph, and the second IQI shows an acceptable sensitivity in the least optically dense portion of the radiograph, the two IQIs
shall serve to qualify the radiograph within these optical density limits plus the +30 % ⁄–15 % of 6.17. Additional IQIs may be used,
as necessary in subsequent exposures, to cover the entire thickness range of the object. For components such as castings and
forgings, where there are changes in wall thickness and wall alignment and the use of two IQIs is not possible, the use of one IQI
E1742/E1742M − 23
is acceptable. The IQI thickness shall be based on the thinnest wall being radiographed and shall be placed on the thickest wall
section. The required +30required +30 % to −15 % optical density tolerance (see 6.17), need not be met; however, the optical
density in the areas of interest shall be between 1.5 and 4.0 (and up to 4.5 by agreement of CEO; see Note 1 of Fig. 1) and the
required radiographic quality level shall be obtained.
6.18 Non-Requirement of IQIs—The IQIs are not required when:
6.18.1 Examining assemblies for debris,
6.18.2 Conducting radiography for defect removal provided final examination of the area includes an IQI,
6.18.3 Examining to show material details or contrast between two or more dissimilar materials in component parts or assemblies
including honeycomb areas for the detection of fabrication irregularities or the presence or absence of material, or
6.18.4 When surfaces are inaccessible an alternate method of qualification shall be used subject to the approval of the cognizant
engineering organization.
6.19 Fabrication Welds—Fabrication welds shall be processed in accordance with Annex A2.
6.20 IQI Selection for Explosives/Propellants, Rocket Motors, and Their Components—The
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