ASTM E94-00
(Guide)Standard Guide for Radiographic Examination
Standard Guide for Radiographic Examination
SCOPE
1.1 This guide covers satisfactory X-ray and gamma-ray radiographic examination as applied to industrial radiographic film recording. It includes statements about preferred practice without discussing the technical background which justifies the preference. A bibliography of several textbooks and standard documents of other societies is included for additional information on the subject.
1.2 This guide covers types of materials to be inspected; radiographic testing techniques and production methods; radiographic film selection, processing, viewing, and storage; maintenance of inspection records; and a list of available reference radiograph documents. Note 1-Further information is contained in Guide E999, Practice E1025, Test Method E1030, and Method E1032.
1.3 Interpretation and Acceptance Standards -Interpretation and acceptance standards are not covered by this guide, beyond listing the available reference radiograph documents for castings and welds. Designation of accept - reject standards is recognized to be within the cognizance of product specifications and generally a matter of contractual agreement between producer and purchaser.
1.4 Safety Practices -Problems of personnel protection against X rays and gamma rays are not covered by this document. For information on this important aspect of radiography, reference should be made to the current document of the National Committee on Radiation Protection and Measurement, Federal Register, U.S. Energy Research and Development Administration, National Bureau of Standards, and to state and local regulations, if such exist.
1.5 This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. (See 1.4.)
1.6 If an NDT agency is used, the agency shall be qualified in accordance with Practice E543.
General Information
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Standards Content (Sample)
NOTICE: This standard has either been superceded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
Designation: E 94 – 00
Standard Guide for
Radiographic Examination
This standard is issued under the fixed designation E 94; 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 (e) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the Department of Defense.
1. Scope responsibility of the user of this standard to establish appro-
priate safety and health practices and determine the applica-
1.1 This guide covers satisfactory X-ray and gamma-ray
bility of regulatory limitations prior to use. (See 1.4.)
radiographic examination as applied to industrial radiographic
1.6 If an NDT agency is used, the agency shall be qualified
film recording. It includes statements about preferred practice
in accordance with Practice E 543.
without discussing the technical background which justifies the
preference. A bibliography of several textbooks and standard
2. Referenced Documents
documents of other societies is included for additional infor-
2.1 ASTM Standards:
mation on the subject.
E 543 Practice for Evaluating Agencies that Perform Non-
1.2 This guide covers types of materials to be examined;
destructive Testing
radiographic examination techniques and production methods;
E 746 Test Method for Determining Relative Image Quality
radiographic film selection, processing, viewing, and storage;
Response of Industrial Radiographic Film
maintenance of inspection records; and a list of available
E 747 Practice for Design, Manufacture, and Material
reference radiograph documents.
Grouping Classification of Wire Image Quality Indicators
NOTE 1—Further information is contained in Guide E 999, Practice
(IQI) Used for Radiology
E 1025, Test Methods E 1030 and E 1032.
E 801 Practice for Controlling Quality of Radiological Ex-
1.3 Interpretation and Acceptance Standards—
amination of Electronic Devices
Interpretation and acceptance standards are not covered by this
E 999 Guide for Controlling the Quality of Industrial Ra-
guide, beyond listing the available reference radiograph docu-
diographic Film Processing
ments for castings and welds. Designation of accept - reject
E 1025 Practice for Design, Manufacture, and Material
standards is recognized to be within the cognizance of product
Grouping Classification of Hole-Type Image Quality Indi-
specifications and generally a matter of contractual agreement
cators (IQI) Used for Radiology
between producer and purchaser.
E 1030 Test Method for Radiographic Examination of Me-
1.4 Safety Practices—Problems of personnel protection
tallic Castings
against X rays and gamma rays are not covered by this
E 1032 Test Method for Radiographic Examination of
document. For information on this important aspect of radiog-
Weldments
raphy, reference should be made to the current document of the
E 1079 Practice for Calibration of Transmission Densitom-
National Committee on Radiation Protection and Measure-
eters
ment, Federal Register, U.S. Energy Research and Develop-
E 1254 Guide for Storage of Radiographs and Unexposed
ment Administration, National Bureau of Standards, and to
Industrial Radiographic Films
state and local regulations, if such exist. For secific radiation
E 1316 Terminology for Nondestructive Examinations
safety information refer to NIST Handbook ANSI 43.3, 21
E 1390 Guide for Illuminators Used for Viewing Industrial
CFR 1020.40, and 29 CFR 1910.1096 or state regulations for
Radiographs
agreement states.
E 1735 Test Method for Determining Relative Image Qual-
1.5 This standard does not purport to address all of the
ity of Industrial Radiographic Film Exposed to
safety problems, if any, associated with its use. It is the
X-Radiation from 4 to 25 MV
E 1742 Practice for Radiographic Examination
E 1815 Test Method for Classification of Film Systems for
1 3
This guide is under the jurisdiction of ASTM Committee E-7 on Nondestructive
Industrial Radiography
Testing and is the direct responsibility of Subcommittee E07.01 on Radiology (X
2.2 ANSI Standards:
and Gamma) Method.
Current edition approved March 10, 2000. Published May 2000. Originally
published as E 94 – 52 T. Last previous edition E 94 – 93.
For ASME Boiler and Pressure Vessel Code applications see related Guide
SE-94 in Section V of that Code. Annual Book of ASTM Standards, Vol 03.03.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
NOTICE: This standard has either been superceded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
E94–00
PH1.41 Specifications for Photographic Film for Archival 5.1.6 Source to film distance,
Records, Silver-Gelatin Type, on Polyester Base
5.1.7 Image quality indicators (IQI’s),
PH2.22 Methods for Determining Safety Times of Photo-
5.1.8 Screens and filters,
graphic Darkroom Illumination
5.1.9 Geometry of part or component configuration,
PH4.8 Methylene Blue Method for Measuring Thiosulfate
5.1.10 Identification and location markers, and
and Silver Densitometric Method for Measuring Residual
Chemicals in Films, Plates, and Papers 5.1.11 Radiographic quality level.
T9.1 Imaging Media (Film)—Silver-Gelatin Type Specifi-
cations for Stability
6. Radiographic Quality Level
T9.2 Imaging Media—Photographic Process Film Plate and
6.1 Information on the design and manufacture of image
Paper Filing Enclosures and Storage Containers
quality indicators (IQI’s) can be found in Practices E 747,
2.3 Federal Standards:
E 801, E 1025, and E 1742.
Title 21, Code of Federal Regulations (CFR) 1020.40,
6.2 The quality level usually required for radiography is
Safety Requirements of Cabinet X-Ray Systems
2 % (2-2T when using hole type IQI) unless a higher or lower
Title 29, Code of Federal Regulations (CFR) 1910.96,
quality is agreed upon between the purchaser and the supplier.
Ionizing Radiation (X-Rays, RF, etc.)
At the 2 % subject contrast level, three quality levels of
2.4 Other Document:
inspection, 2-1T, 2-2T, and 2-4T, are available through the
NBS Handbook ANSI N43.3 General Radiation Safety
design and application of the IQI (Practice E 1025, Table 1).
Installations Using NonMedical X-Ray and Sealed
Other levels of inspection are available in Practice E 1025
Gamma Sources up to 10 MeV
Table 1. The level of inspection specified should be based on
3. Terminology
the service requirements of the product. Great care should be
taken in specifying quality levels 2-1T, 1-1T, and 1-2T by first
3.1 Definitions—For definitions of terms used in this guide,
refer to Terminology E 1316. determining that these quality levels can be maintained in
production radiography.
4. Significance and Use
NOTE 2—The first number of the quality level designation refers to IQI
4.1 Within the present state of the radiographic art, this
thickness expressed as a percentage of specimen thickness; the second
guide is generally applicable to available materials, processes,
number refers to the diameter of the IQI hole that must be visible on the
and techniques where industrial radiographic films are used as
radiograph, expressed as a multiple of penetrameter thickness, T.
the recording media.
6.3 If IQI’s of material radiographically similar to that being
4.2 Limitations—This guide does not take into consider-
examined are not available, IQI’s of the required dimensions
ation special benefits and limitations resulting from the use of
but of a lower-absorption material may be used.
nonfilm recording media or readouts such as paper, tapes,
xeroradiography, fluoroscopy, and electronic image intensifi- 6.4 The quality level required using wire IQI’s shall be
equivalent to the 2-2T level of Practice E 1025 unless a higher
cation devices. Although reference is made to documents that
may be used in the identification and grading, where appli- or lower quality level is agreed upon between purchaser and
cable, of representative discontinuities in common metal cast- supplier. Table 4 of Practice E 747 gives a list of various
ings and welds, no attempt has been made to set standards of hole-type IQI’s and the diameter of the wires of corresponding
acceptance for any material or production process. Radiogra- EPS with the applicable 1T, 2T, and 4T holes in the plaque IQI.
phy will be consistent in sensitivity and resolution only if the
Appendix X1 of Practice E 747 gives the equation for calcu-
effect of all details of techniques, such as geometry, film, lating other equivalencies, if needed.
filtration, viewing, etc., is obtained and maintained.
7. Energy Selection
5. Quality of Radiographs
7.1 X-ray energy affects image quality. In general, the lower
5.1 To obtain quality radiographs, it is necessary to consider
the energy of the source utilized the higher the achievable
as a minimum the following list of items. Detailed information
radiographic contrast, however, other variables such as geom-
on each item is further described in this guide.
etry and scatter conditions may override the potential advan-
5.1.1 Radiation source (x-ray or gamma),
tage of higher contrast. For a particular energy, a range of
5.1.2 Voltage selection (x-ray),
thicknesses which are a multiple of the half value layer, may be
5.1.3 Source size (x-ray or gamma),
radiographed to an acceptable quality level utilizing a particu-
5.1.4 Ways and means to eliminate scattered radiation,
lar X-ray machine or gamma ray source. In all cases the
5.1.5 Film system class,
specified IQI (penetrameter) quality level must be shown on
the radiograph. In general, satisfactory results can normally be
obtained for X-ray energies between 100 kV to 500 kV in a
Available from American National Standards Institute, 11 West 42nd Street,
13th Floor, New York, NY 10036.
range between 2.5 to 10 half value layers (HVL) of material
Available from U.S. Government Printing Office, Superintendent of Docu-
thickness (see Table 1). This range may be extended by as
ments, Vashington, DC 20402.
6 much as a factor of 2 in some situations for X-ray energies in
Available from the National Technical Information Service, 5285 Port Royal
Road, Springfield, VA 22161. the 1 to 25 MV range primarily because of reduced scatter.
NOTICE: This standard has either been superceded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
E94–00
TABLE 1 Typical Steel HVL Thickness in Inches (mm) for
associated film processing system. Users may obtain a classi-
Common Energies
fication table from the film manufacturer for the film system
Thickness,
used in production radiography. A choice of film class can be
Energy
Inches (mm)
made as provided in Test Method E 1815. Additional specific
120 kV 0.10 (2.5)
details regarding classification of film systems is provided in
150 kV 0.14 (3.6)
Test Method E 1815. ANSI Standards PH1.41, PH4.8, T9.1,
200 kV 0.20 (5.1)
250 kV 0.25 (6.4) and T9.2 provide specific details and requirements for film
400 kV (Ir 192) 0.35 (8.9)
manufacturing.
1 MV 0.57 (14.5)
2 MV (Co 60) 0.80 (20.3)
4 MV 1.00 (25.4)
10. Filters
6 MV 1.15 (29.2)
10.1 Definition—Filters are uniform layers of material
10 MV 1.25 (31.8)
16 MV and higher 1.30 (33.0)
placed between the radiation source and the film.
10.2 Purpose—The purpose of filters is to absorb the softer
components of the primary radiation, thus resulting in one or
several of the following practical advantages:
8. Radiographic Equivalence Factors
10.2.1 Decreasing scattered radiation, thus increasing con-
8.1 The radiographic equivalence factor of a material is that
trast.
factor by which the thickness of the material must be multi-
10.2.2 Decreasing undercutting, thus increasing contrast.
plied to give the thickness of a “standard” material (often steel)
10.2.3 Decreasing contrast of parts of varying thickness.
which has the same absorption. Radiographic equivalence
10.3 Location—Usually the filter will be placed in one of
factors of several of the more common metals are given in
the following two locations:
Table 2, with steel arbitrarily assigned a factor of 1.0. The
10.3.1 As close as possible to the radiation source, which
factors may be used:
minimizes the size of the filter and also the contribution of the
8.1.1 To determine the practical thickness limits for radia-
filter itself to scattered radiation to the film.
tion sources for materials other than steel, and
10.3.2 Between the specimen and the film in order to absorb
8.1.2 To determine exposure factors for one metal from
preferentially the scattered radiation from the specimen. It
exposure techniques for other metals.
should be noted that lead foil and other metallic screens (see
13.1) fulfill this function.
9. Film
10.4 Thickness and Filter Material— The thickness and
9.1 Various industrial radiographic film are available to
material of the filter will vary depending upon the following:
meet the needs of production radiographic work. However,
10.4.1 The material radiographed.
definite rules on the selection of film are difficult to formulate
10.4.2 Thickness of the material radiographed.
because the choice depends on individual user requirements.
10.4.3 Variation of thickness of the material radiographed.
Some user requirements are as follows: radiographic quality
10.4.4 Energy spectrum of the radiation used.
levels, exposure times, and various cost factors. Several
10.4.5 The improvement desired (increasing or decreasing
methods are available for assessing image quality levels (see
contrast). Filter thickness and material can be calculated or
Test Method E 746, and Practices E 747 and E 801). Informa-
determined empirically.
tion about specific products can be obtained from the manu-
facturers.
11. Masking
9.2 Various industrial radiographic films are manufactured
to meet quality level and production needs. Test Method 11.1 Masking or blocking (surrounding specimens or cov-
E 1815 provides a method for film manufacturer classification ering thin sections with an absorptive material) is helpful in
of film systems. A film system consist of the film and reducing scattered radiation. Such a material can also be used
TABLE 2 Approximate Radiographic Equivalence Factors for Several Metals (Relative to Steel)
Energy Level
Metal
192 60
100 kV 150 kV 220 kV 250 kV 400 kV 1 MV 2 MV 4 to 25 MV Ir Co
Magnesium 0.05 0.05 0.08
Aluminum 0.08 0.12 0.18 0.35 0.35
Aluminum alloy 0.10 0.14 0.18 0.35 0.35
Titanium 0.54 0.54 0.71 0.9 0.9 0.9 0.9 0.9
Iron/all steels 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0
Copper 1.5 1.6 1.
...
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