ASTM E1000-98(2003)

Standard Guide for Radioscopy

SIGNIFICANCE AND USE
Radioscopy is a versatile nondestructive means for examining an object. It provides immediate information regarding the nature, size, location, and distribution of imperfections, both internal and external. It also provides a rapid check of the dimensions, mechanical configuration, and the presence and positioning of components in a mechanism. It indicates in real-time the presence of structural or component imperfections anywhere in a mechanism or an assembly. Through manipulation, it may provide three-dimensional information regarding the nature, sizes, and relative positioning of items of interest within an object, and can be further employed to check the functioning of internal mechanisms. Radioscopy permits timely assessments of product integrity, and allows prompt disposition of the product based on acceptance standards. Although closely related to the radiographic method, it has much lower operating costs in terms of time, manpower, and material.
Long-term records of the radioscopic image may be obtained through motion-picture recording (cinefluorography), video recording, or “still” photographs using conventional cameras. The radioscopic image may be electronically enhanced, digitized, or otherwise processed for improved visual image analysis or automatic, computer-aided analysis, or both.
SCOPE
1.1 This guide is for tutorial purposes only and to outline the general principles of radioscopic imaging.
1.2 This guide describes practices and image quality measuring systems for real-time, and near real-time, nonfilm detection, display, and recording of radioscopic images. These images, used in materials examination, are generated by penetrating radiation passing through the subject material and producing an image on the detecting medium. Although the described radiation sources are specifically X-ray and gamma-ray, the general concepts can be used for other radiation sources such as neutrons. The image detection and display techniques are nonfilm, but the use of photographic film as a means for permanent recording of the image is not precluded.
Note 1—For information purposes, refer to Terminology E 1316.
1.3 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 and health practices and determine the applicability of regulatory limitations prior to use. For specific safety precautionary statements, see Section .

General Information

• Status: Historical
• Publication Date: 09-Mar-2003
• ICS: 19.100 - Non-destructive testing
• Technical Committee: E07 - Nondestructive Testing
• Drafting Committee: E07.01 - Radiology (X and Gamma) Method

Relations

• Replaces: ASTM E1000-98 - Standard Guide for Radioscopy
• Effective Date: 10-Mar-2003
• Replaced By: ASTM E1000-98(2009) - Standard Guide for Radioscopy
• Effective Date: 01-Jun-2009
• Referred By: ASTM E1734-23 - Standard Practice for Radioscopic Examination of Castings
• Effective Date: 10-Mar-2003
• Referred By: ASTM E1416-23 - Standard Practice for Radioscopic Examination of Weldments
• Effective Date: 10-Mar-2003
• Referred By: ASTM E2533-21 - Standard Guide for Nondestructive Examination of Polymer Matrix Composites Used in Aerospace Applications
• Effective Date: 10-Mar-2003
• Referred By: ASTM E1475-13(2023) - Standard Guide for Data Fields for Computerized Transfer of Digital Radiological Examination Data
• Effective Date: 10-Mar-2003
• Referred By: ASTM E1453-20 - Standard Guide for Storage of Magnetic Tape Media that Contains Analog or Digital Radioscopic Data
• Effective Date: 10-Mar-2003
• Referred By: ASTM E1165-20 - Standard Test Method for Measurement of Focal Spots of Industrial X-Ray Tubes by Pinhole Imaging
• Effective Date: 10-Mar-2003
• Referred By: ASTM E1255-16 - Standard Practice for Radioscopy
• Effective Date: 10-Mar-2003
• Referred By: ASTM E1161-21 - Standard Practice for Radiographic Examination of Semiconductors and Electronic Components
• Effective Date: 10-Mar-2003
• Referred By: ASTM E1695-20e1 - Standard Test Method for Measurement of Computed Tomography (CT) System Performance
• Effective Date: 10-Mar-2003
• Referred By: ASTM E2736-17(2022) - Standard Guide for Digital Detector Array Radiography
• Effective Date: 10-Mar-2003
• Referred By: ASTM E2662-15(2022) - Standard Practice for Radiographic Examination of Flat Panel Composites and Sandwich Core Materials Used in Aerospace Applications
• Effective Date: 10-Mar-2003
• Referred By: ASTM E1817-08(2022) - Standard Practice for Controlling Quality of Radiological Examination by Using Representative Quality Indicators (RQIs)
• Effective Date: 10-Mar-2003
• Referred By: ASTM E94/E94M-22 - Standard Guide for Radiographic Examination Using Industrial Radiographic Film
• Effective Date: 10-Mar-2003

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: E 1000 – 98 (Reapproved 2003)
Standard Guide for
Radioscopy
This standard is issued under the fixed designation E1000; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope NCRP49 Structural Shielding Design and Evaluation for
Medical Use of X Rays and Gamma Rays of Energies up
1.1 Thisguideisfortutorialpurposesonlyandtooutlinethe
to 10 MeV
general principles of radioscopic imaging.
NCRP 51 Radiation Protection Design Guidelines for
1.2 This guide describes practices and image quality mea-
0.1–100 MeV Particle Accelerator Facilities
suring systems for real-time, and near real-time, nonfilm
NCRP91, (supercedes NCRP 39) Recommendations on
detection, display, and recording of radioscopic images. These
Limits for Exposure to Ionizing Radiation
images, used in materials examination, are generated by
2.3 Federal Standard:
penetrating radiation passing through the subject material and
Fed. Std. No.21-CFR 1020.40 Safety Requirements for
producing an image on the detecting medium. Although the
Cabinet X-Ray Machines
described radiation sources are specifically X-ray and gamma-
ray, the general concepts can be used for other radiation
3. Summary of Guide
sources such as neutrons. The image detection and display
3.1 This guide outlines the practices for the use of radio-
techniques are nonfilm, but the use of photographic film as a
scopicmethodsandtechniquesformaterialsexaminations.Itis
means for permanent recording of the image is not precluded.
intended to provide a basic understanding of the method and
NOTE 1—For information purposes, refer to Terminology E1316.
the techniques involved. The selection of an imaging device,
radiation source, and radiological and optical techniques to
1.3 This standard does not purport to address all of the
safety concerns, if any, associated with its use. It is the achieve a specified quality in radioscopic images is described.
responsibility of the user of this standard to establish appro-
4. Significance and Use
priate safety and health practices and determine the applica-
4.1 Radioscopy is a versatile nondestructive means for
bility of regulatory limitations prior to use. For specific safety
examining an object. It provides immediate information re-
precautionary statements, see Section 6.
garding the nature, size, location, and distribution of imperfec-
2. Referenced Documents
tions, both internal and external. It also provides a rapid check
of the dimensions, mechanical configuration, and the presence
2.1 ASTM Standards:
E142 Method for Controlling Quality of Radiographic and positioning of components in a mechanism. It indicates in
real-time the presence of structural or component imperfec-
Testing
E 747 Practice for Design, Manufacture and Material tions anywhere in a mechanism or an assembly. Through
manipulation, it may provide three-dimensional information
Grouping Classification of Wire Image Quality Indicators
(IQI) Used for Radiology regarding the nature, sizes, and relative positioning of items of
interestwithinanobject,andcanbefurtheremployedtocheck
E1025 Practice for Design, Manufacture, and Material
Grouping Classification of Hole-Type Image Quality Indi- the functioning of internal mechanisms. Radioscopy permits
timely assessments of product integrity, and allows prompt
cators (IQI) Used for Radiology
E1316 Terminology for Nondestructive Examinations disposition of the product based on acceptance standards.
Although closely related to the radiographic method, it has
E2002 Practice for Determining Total Image Unsharpness
in Radiology much lower operating costs in terms of time, manpower, and
material.
2.2 National Council on Radiation Protection and Mea-
surement (NCRP) Standards: 4.2 Long-term records of the radioscopic image may be
obtained through motion-picture recording (cinefluorography),
This guide is under the jurisdiction of ASTM Committee E07 on Nondestruc-
tive Testing and is the direct responsibility of Subcommittee E07.01 on Radiology
Available from NCRP Publications, 7010 Woodmont Ave., Suite 1016, Be-
(X and Gamma) Method.
Current edition approved March 10, 2003. Published May 2003. Originally thesda, MD 20814.
approved in 1989. Last previous edition approved in 1998 as E1000-98. AvailablefromStandardizationDocumentsOrderDesk,Bldg.4SectionD,700
Annual Book of ASTM Standards, Vol 03.03. Robbins Ave., Philadelphia, PA 19111-5094, Attn: NPODS.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
E 1000 – 98 (2003)
video recording, or “still” photographs using conventional tubes, such as the isocon, intensifier orthicon, and secondary
cameras. The radioscopic image may be electronically en- electron conduction (SEC) vidicon, and the advent of ad-
hanced, digitized, or otherwise processed for improved visual vanced, low-noise video circuitry have made it possible to use
image analysis or automatic, computer-aided analysis, or both. television cameras to scan conventional, high-resolution, low-
light-output fluorescent screens directly. The results are com-
5. Background
parable to those obtained with the image intensifier.
5.1 Fluorescence was the means by which X rays were
5.3 In recent years (circa 1980’s) new digital radiology
discovered, but industrial fluoroscopy began some years later
techniques have been developed. These methods produce
with the development of more powerful radiation sources and
directly digitized representations of the X-ray field transmitted
improved screens. Fluoroscopic screens typically consist of
by an examination article. Direct digitization enhances the
phosphors that are deposited on a substrate. They emit light in
signal-to-noiseratioofthedataandpresentstheinformationin
proportion to incident radiation intensity, and as a function of
a form directly suitable for electronic image processing and
the composition, thickness, and grain size of the phosphor
enhancement, and storage on magnetic tape. Digital radio-
coating. Screen brightness is also a function of the wavelength
scopic systems use scintillator-photodetector and phosphor-
of the impinging radiation. Screens with coarse-grained or
photodetector sensors in flying spot and fan beam-detector
thick coatings of phosphor, or both, are usually brighter but
array arrangements.
have lower resolution than those with fine grains or thin
5.4 All of these techniques employ television presentation
coatings, or both. In the past, conventional fluorescent screens
and can utilize various electronic techniques for image en-
limited the industrial applications of fluoroscopy. The light
hancement, image storage, and video recording. These ad-
output of suitable screens was quite low (on the order of 0.1
vanced imaging devices, along with modern video processing
−3 2
millilambertor0.343 310 cd/m )andrequiredabout30min
and analysis techniques, have greatly expanded the versatility
for an examiner to adapt his eyes to the dim image. To protect
of radioscopic imaging. Industrial applications have become
the examiner from radiation, the fluoroscopic image had to be
wide-spread:productionexaminationofthelongitudinalfusion
viewed through leaded glass or indirectly using mirror optics.
welds in line pipe, welds in rocket-motor housings, castings,
Such systems were used primarily for the examination of
transistors, microcircuits, circuit-boards rocket propellant uni-
light-alloy castings, the detection of foreign material in food-
formity, solenoid valves, fuses, relays, tires and reinforced
stuffs, cotton and wool, package inspection, and checking
plastics are typical examples.
weldments in thin or low-density metal sections.The choice of
5.5 Limitations—Despite the numerous advances in RRTI
fluoroscopy over radiography was generally justified where
technology, the sensitivity and resolution of real-time systems
time and cost factors were important and other nondestructive
usually are not as good as can be obtained with film. In
methods were not feasible.
radiography the time exposures and close contact between the
5.2 It was not until the early 1950’s that technological
film and the subject, the control of scatter, and the use of
advances set the stage for widespread uses of industrial
screens make it relatively simple to obtain better than 2%
fluoroscopy. The development of the X-ray image intensifier
penetrameter sensitivity in most cases. Inherently, because of
provided the greatest impetus. It had sufficient brightness gain
statistical limitations dynamic scenes require a higher X-ray
tobringfluoroscopicimagestolevelswhereexaminationcould
flux level to develop a suitable image than static scenes. In
be performed in rooms with somewhat subdued lighting, and
addition, the product-handling considerations in a dynamic
without the need for dark adaption. These intensifiers con-
imaging system mandate that the image plane be separated
tained an input phosphor to convert the X rays to light, a
from the surface of the product resulting in perceptible image
photocathode (in intimate contact with the input phosphor) to
unsharpness. Geometric unsharpness can be minimized by
convert the light image into an electronic image, electron
employing small focal spot (fractions of a millimetre) X-ray
accelerating and focusing electrodes, and a small output
sources, but this requirement is contrary to the need for the
phosphor.Intensifierbrightnessgainresultsfromboththeratio
high X-ray flux density cited previously. Furthermore, limita-
of input to output phosphor areas and the energy imparted to
tions imposed by the dynamic system make control of scatter
the electrons. Early units had brightness gains of around 1200
and geometry more difficult than in conventional radiographic
to 1500 and resolutions somewhat less than high-resolution
systems. Finally, dynamic radioscopic systems require careful
conventional screens. Modern units utilizing improved phos-
alignment of the source, subject, and detector and often
phors and electronics have brightness gains in excess of
expensive product-handling mechanisms. These, along with
10 0003andimprovedresolution.Forexample,weldsinsteel
the radiation safety requirements peculiar to dynamic systems
thicknesses up to 28.6 mm [1.125 in.] can be examined at 2%
usuallyresultincapitalequipmentcostsconsiderablyinexcess
plaque penetrameter sensitivity using a 160 constant potential
ofthatforconventionalradiography.Thecostsofexpendables,
X-ray generator (keVcp) source. Concurrent with image-
manpower, product-handling and time, however, are usually
intensifier developments, direct X ray to television-camera
significantly lower for radioscopic systems.
tubes capable of high sensitivity and resolution on low-density
6. Safety Precautions
materialsweremarketed.Becausetheyrequireacomparatively
high X-ray flux input for proper operation, however, their use 6.1 The safety procedures for the handling and use of
has been limited to examination of low-density electronic ionizing radiation sources must be followed. Mandatory rules
components, circuit boards, and similar applications. The and regulations are published by governmental licensing agen-
development of low-light level television (LLLTV) camera cies, and guidelines for control of radiation are available in
E 1000 – 98 (2003)
publications such as the Fed. Std. No. 21-CFR 1020.40. loosely bound electrons from the inner shells of atoms with
Careful radiation surveys should be made in accordance with which they collide. These photoelectrons have energies pro-
regulations and codes and should be conducted in the exami- portional to the original X-ray photon and can be utilized in a
nation area as well as adjacent areas under all possible variety of ways to produce images, including the following
operating conditions. useful processes.
8.4.1 Energizing of Semiconductor Junctions—The resis-
7. Interpretation and Reference Standards
tance of a semiconductor, or of a semiconductor junction in a
7.1 Reference radiographs produced by ASTM and accep-
device such as a diode or transistor, can be altered by adding
tance standards written by other organizations may be em-
free electrons. The energy of an X-ray photon is capable of
ployed for radioscopic examination as well as for radiography,
freeing electrons in such materials and can profoundly affect
provided appropriate adjustments are made to accommodate
the operation of the device. For example, a simple silicon
for the differences in the fluoroscopic images.
“solar cell” connected to a microammeter will produce a
substantial current when exposed to an X-ray source.
8. Radioscopic Devices, Classification
8.4.1.1 If an array of small semiconductor devices is ex-
8.1 The most commonly used electromagnetic radiation in
posedtoanX-raybeam,andtheperformanceofeachdeviceis
radioscopyisproducedbyX-raysources.Xraysareaffectedin
sampled, then an image can be produced by a suitable display
various modes and degrees by passage through matter. This
of the data. Such arrays can be linear or two-dimensional.
providesveryusefulinformationaboutthematterthathasbeen
Linear arrays normally require relative motion between the
traversed. The detection of these X-ray photons in such a way
object and the array to produce a useful real-time image. The
that the information they carry can be used immediately is the
choice depends upon the application.
prime requisite of radioscopy. Since there are many ways of
8.4.2 Affecting Resistance of Semiconductors—The most
detecting the presence of X rays, their energy and flux density,
common example of this is the X-ray sensitive vidicon camera
there are a number of possible systems. Of these, only a few
tube. Here the target layer of the vidicon tube, and its support,
deserve more than the attention caused by scientific curiosity.
are modified to have an improved sensitivity to X-ray photons.
For our purposes here, only these few are classified and
The result is a change in conductivity of the target layer
described.
corresponding to the pattern of X-ray flux falling upon the
8.2 Basic Classification of Radioscopic Systems—All com-
tube,andthisisdirectlytransformedbythescanningbeaminto
monly used systems depend on two basic processes for
a video signal which can be used in a variety of ways.
detecting X-ray photons: X-ray to light conversion and X-ray
8.4.2.1 Photoconductive materials that exhibit X-ray sensi-
to electron conversion.
tivity include cadmium sulfide, cadmium selenide, lead oxi
...