ASTM F947-85(1996)

Standard Test Method for Determining Low-Level X-Radiation Sensitivity of Photographic Films (Withdrawn 2005)

SCOPE
1.1 This test method is for determining the maximum x-ray sensitivity coefficient (slope of diffuse visual density versus x-ray exposure) of film/processing combinations for low quantities of x-ray exposure to silver halide photographic film. This coefficient can be used to assess the relative susceptibility of films to damage from x-ray exposure, such as that encountered in airport and similar security screening systems.  
1.2 This standard may involve hazardous materials, operations, and equipment. This standard does not purport to address all of the safety problems associated with its use. It is the responsibility of whoever uses this standard to consult and establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
WITHDRAWN RATIONALE
This test method determines the maximum x-ray sensitivity coefficient (slope of diffuse visual density versus x-ray exposure) of film/processing combinations for low quantities of x-ray exposure to silver halide photographic film. This coefficient can be used to assess the relative susceptibility of films to damage from x-ray exposure, such as that encountered in airport and similar security screening systems.
Formerly under the jurisdiction of Committee F12 on Security Systems and Equipment, this test method was withdrawn in January 2005 in accordance with section 10.5.3.1 of the Regulations Governing ASTM Technical Committees, which requires that standards shall be updated by the end of the eighth year since the last approval date.

General Information

• Status: Withdrawn
• Publication Date: 31-Dec-1995
• Withdrawal Date: 14-Jan-2005
• ICS: 37.040.20 - Photographic paper, films and plates. Cartridges
• Technical Committee: F12 - Security Systems and Equipment
• Drafting Committee: F12.60 - Controlled Access Security, Search, and Screening Equipment

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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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:F947–85 (Reapproved 1996)
Standard Test Method for
Determining Low-Level X-Radiation Sensitivity of
Photographic Films
This standard is issued under the fixed designation F 947; 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.
1. Scope 4.1.2 The kilovoltage applied to the x-ray tube shall be
adjusted to yield a half-value layer (HVL) of 3.4 6 0.5 mm of
1.1 This test method determines the maximum x-ray sensi-
aluminum as determined with a radiation measuring device
tivity coefficient (slope of diffuse visual density versus x-ray
having a quantum energy response flat within 65 % over the
exposure) of film/processing combinations for low quantities
effective energy range from 30 to 100 keV. That is, with the
of x-ray exposure to silver halide photographic film. This
measuring device at or adjacent to the film exposing position,
coefficient can be used to assess the relative susceptibility of
the tube kilovoltage shall be adjusted such that the introduc-
films to damage from x-ray exposure, such as that encountered
tion of 3.4 mm of aluminum into the x-ray beam close to the
in airport and similar security screening systems.
tube, in addition to the filtration specified in 4.1.1, will reduce
1.2 This standard does not purport to address all of the
the measured x-ray intensity to 50 6 1 % of its value without
safety concerns, if any, associated with its use. It is the
this HVL aluminum in the beam. The HVL aluminum must of
responsibility of the user of this standard to establish appro-
course be removed for subsequent film exposure and exposure
priate safety and health practices and determine the applica-
measurement.
bility of regulatory limitations prior to use.
4.2 Secondary X-Rays:
2. Referenced Documents
4.2.1 To minimize secondary radiation during dosimetry
and exposure of test films, x-ray beams shall be diaphragmed
2.1 ANSI Standard
to as small a size as will properly include the exposure area for
PH2.19 (1976) American National Standard Conditions for
the films (and exposure measuring device, if included). Except
Diffuse and Doubly-Diffuse Transmission Measurements
for a 1 mm minimum thickness sheet of lead for backing the
(Transmission Density)
film container, the lightest supports possible of low-atomic-
3. Significance and Use
number material shall be used for supporting the film and
exposure measuring device. Other materials in the x-ray beam
3.1 The x-ray sensitivity coefficient is used to estimate the
shall be kept at least 50 cm distant from the film. The amount
amount of x-ray exposure that would produce a visually
of secondary radiation reaching the film and measuring device
significant effect on a film. This value may be useful in
shall be less than 3 % of the primary x-rays.
establishingmaximumallowablex-raydosesforclassesoffilm
4.2.2 The presence of secondary (scattered) radiation shall
products, for example, consumer color films, scientific and
be tested by plotting the inverse square root of the exposure
x-ray films, etc.
rate as a function of distance from the source. Absence of
4. Calibration and Standardization
significant secondary radiation is indicated when the resulting
plot is a straight line passing through the origin. Such radiation
4.1 Radiant Energy Quality:
is excessive if the point corresponding to the observed expo-
4.1.1 Tungsten target x-ray tubes shall be used to expose
sure rate at the distance used for film exposures is more than
test films. Inherent filtration of the tube plus an additional
3 % below the best straight line from the origin among the
aluminum filter located as close to the x-ray tube as possible
plotted points. Measurements shall be made at enough dis-
shall provide a total filtration equivalent to 3.7 6 0.5 mm of
tances to provide a reliable indication of secondary radiation
aluminum.
reaching the exposure plane and shall include distances ap-
proximately equally spaced from one-half that between the
This test method is under the jurisdiction of ASTM Committee F-12 on
Security Systems and Equipment and is the direct responsibility of Subcommittee
F12.60 on Controlled Access Security, Search and Screening Equipment.
Current edition approved July 26, 1985. Published October 1985.
2 4
Available from American National Standards Institute, 11 W. 42nd St., 13th The HVL specification should be satisfied with approximately 80 kV constant
Floor, New York, NY 10036. potential, approximately 80 kVp 3-phase, or approximately 95 kVp single phase
Aluminum Association Alloy 1100, or the equivalent. applied to the x-ray tube.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
F947–85 (1996)
FIG. 1 Plot of Net Density versus Exposure for a Negative Film Product
x-ray tube focal spot and exposure plane to at least 10 % posed density (D of negative films or D of reversal pro-
fog max
beyond the exposure plane, if possible (film container and lead cessed positive films). Then separate areas or samples of the
backing removal). filmshallbeexposedtoeachofagraduatedseriesofexposures
under the conditions specified in Section 3, such as will result
5. Conditioning
in a series of at least five densitites differing by no more than
5.1 The temperature of the film during exposure shall be 20 0.1 D from the density of the unexposed film. The exposure
increments for the series shall be arithmetic in progression and
6 5°C. The moisture content of the film shall be such that the
may be obtained by varying either exposure rate or exposure
film will be in equilibrium with a relative humidity ranging
time including if desired, accumulation by repetition of the
from 30 to 70 %.
minimum increment (intermittent exposure). For example, if
6. Procedure
15 mR of exposure on a particular film produced a density
change of no more than 0.1 D from that of an unexposed area
6.1 Safelights—All films shall be loaded, handled, and
of the film, then exposure No. 1 of the series could be 3 mR,
processed
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