TITLE 32: ENERGY
CHAPTER II: DEPARTMENT OF NUCLEAR SAFETY
SUBCHAPTER b: RADIATION PROTECTION
PART 360
USE OF X-RAYS IN THE HEALING ARTS INCLUDING MEDICAL, DENTAL,
PODIATRY, AND VETERINARY MEDICINE
Section
360.10 Scope
360.20 Definitions
360.30 General Requirements and Administrative Controls
360.40 General Equipment and Operation Requirements for Diagnostic X-Ray
Systems
360.50 Fluoroscopic Systems
360.60 Stationary Radiographic Systems Other Than Fluoroscopic, Dental
Intraoral, Veterinary, or Systems Used Solely for Mammography
360.70 Mobile/Portable Radiographic Systems Other Than Systems Used
Solely for Mammography
360.71 Requirements for Facilities Performing Mammography
360.80 Photofluorographic Systems
360.90 Intraoral Dental Radiographic Systems
360.100 Veterinary Radiographic Systems
360.110 Therapeutic X-Ray Installations
360.120 Special Requirements for X-Ray Therapy Equipment Operated at
Potential of Fifty (50) kVp and Below
360.APPENDIX A Medical Radiographic Exposure Limits
360.APPENDIX B Mammography Dose Limit
360.ILLUSTRATION A Thimble and Pancake Chamber - Radiation Measuring Devices
360.ILLUSTRATION B Mammography Dose Evaluation Graph
360.TABLE A Filtration Required as a Function of Operating kVp (Repealed)
360.TABLE B Half-Value Layer as a Function of Tube Potential
360.TABLE C Entrance Exposure Limits Per Intraoral Bitewing Film
AUTHORITY: Implementing and authorized by the Radiation Protection Act of
1990 (P.A. 86-1341, effective September 7, 1990)
SOURCE: Filed April 20, 1974 by the Department of Public Health; old rules
repealed, new rules adopted at 4 Ill. Reg. 25, p. 157, effective July 1, 1980;
transferred to the Department of Nuclear Safety by P.A. 81-1516, effective
December 3, 1980; codified at 7 Ill. Reg. 16406; amended at 10 Ill. Reg.
13271, effective July 28, 1986; amended at 13 Ill. Reg. 803, effective
April 1, 1989; amended at 15 Ill. Reg. 6180, effective April 16, 1991.
Section 360.10 Scope
a) This Part establishes requirements for use of x-ray producing
devices in the healing arts by a practitioner licensed to practice
a treatment of human ailments by virtue of the Medical Practice
Act of 1987 (Ill. Rev. Stat. 1987, ch. 111, pars. 4400-1 et seq.),
the Illinois Dental Practice Act (Ill. Rev. Stat. 1987, ch. 111,
pars. 2301 et seq.), or the Podiatric Medical Practice Act of 1987
(Ill. Rev. Stat. 1987, ch. 111, pars. 4801 et seq.), or by a
medical radiographer or radiation therapy technologist accredited
in accordance with the provision of 32 Ill. Adm. Code 401.100 or
an individual exempt from the provisions of 32 Ill. Adm. Code 401,
by Section 401.30 of that Part, acting under the supervision,
prescription or direction of such licensed person or the non-human
use of x-ray by veterinarians by virtue of the Veterinary Medicine
and Surgery Practice Act of 1983 (Ill. Rev. Stat. 1987, ch. 111,
pars. 7001 et seq.). The provisions of this Part are in addition
to, and not in substitution for, other applicable provisions of 32
Ill. Adm. Code 310, 320, 340, 400, and 410.
b) It is recognized that some installations and equipment designed
before the adoption of this Part, coupled with conditions of use,
may be adequate to achieve minimum exposures. Request for
exemption from some provisions of this Part will be considered in
accordance with 32 Ill. Adm. Code 310.30(a).
(Source: Amended at 13 Ill. Reg. 803, effective April 1, 1989)
Section 360.20 Definitions
As used in this Part, the following definitions apply:
"Accelerator" means any therapeutic machine capable of producing a
useful beam of x-rays or charged particles with energies greater
than 500 keV.
"Added filtration" means the effect of the material (filter) added
to the inherent filtration.
"Aluminum equivalent" means the thickness of type 1100 aluminum
alloy affording the same attenuation, under specified conditions,
as the material in question. The nominal chemical composition of
type 1100 aluminum alloy is 99.00 percent minimum aluminum, 0.12
percent copper.
"Automatic exposure control" means a device which automatically
controls 1 or more technique factors in order to obtain at a
preselected location(s) a required quantity of radiation (see
"Phototimer").
"Barrier" (see "Protective barrier").
"Beam axis" means a line from the source through the center of the
x-ray field.
"Beam-limiting device" means a device which provides a means to
restrict the dimensions of the x-ray field (see "Collimator",
"Diaphragm", and "Shutter").
"Certified system" means an x-ray system which is subject to
regulations promulgated under Public Law 90-602, the Radiation
Control for Health and Safety Act of 1968 (42 U.S.C.A. 263(b) et
seq.), 21 CFR 1000.3 et seq., in effect as of April 1, 1988,
exclusive of subsequent amendments or editions. A copy of this
document is available for public inspection at the Illinois
Department of Nuclear Safety (Department), 1035 Outer Park Drive,
Springfield, Illinois.
"Collimator" means a device or mechanism by which the x-ray beam
is restricted in size (see "Beam-limiting device").
"Contact therapy system" means an x-ray system used for therapy
with the x-ray tube port placed in contact with or within 5
centimeters of the surface being treated.
"Control panel" means that part or parts of the x-ray system upon
which are mounted the switches, knobs, pushbuttons, and other
hardware necessary for setting the technique factors prior to
initiating an x-ray exposure.
"Dead-man switch" means a switch so constructed that a circuit-
closing contact can be maintained only by continuous pressure on
the switch by the operator.
"Diagnostic source assembly" means an x-ray tube housing assembly,
designed for use in diagnostic x-ray applications, with a beam
limiting device attached.
"Diagnostic-type protective tube housing" means an x-ray tube
housing constructed so that when a beam limiting device is
attached, the leakage radiation measured at a distance of 1 meter
from the source cannot exceed 100 mR in 1 hour when the tube is
operated at its maximum continuous rated current for the maximum
rated tube potential.
"Diaphragm" means a device or mechanism by which the x-ray beam is
restricted in size (see "Beam-limiting device").
"Filter" means material placed in the useful beam to absorb,
preferentially, radiations based on energy level (see
"Filtration" and "Inherent filtration").
"Filtration" means the act of preferentially absorbing radiation
with filters or inherent filtration (see "Filter" and "Inherent
filtration").
"General purpose radiographic x-ray system" means any radiographic
x-ray system which, by design, is not limited to radiographic
examination of specific anatomical regions.
"Gonad shield" means a protective device for the testes or ovaries
which provides a minimum of 0.50 mm lead equivalent protection.
"Half-value layer (HVL)" means the thickness of a specified
material that attenuates the beam of radiation to an extent such
that the exposure rate is reduced to one-half of its original
value.
AGENCY NOTE: The contribution of all scattered radiation, other
than any that might be present initially in the beam concerned, is
minimized.
"Healing arts screening" means the examination of human beings
using x-ray machines for the detection or evaluation of potential
diseases when such examinations are not specifically ordered by a
licensed practitioner of the healing arts legally authorized to
prescribe such x-ray examinations for the purpose of diagnosis or
treatment. However, healing arts screening does not include
mammography on self-referred patients.
"Image intensifier" means a device, installed in a housing, which
converts an x-ray pattern into a corresponding light image.
"Image receptor" means any device, such as a fluorescent screen or
radiographic film, which transforms incident x-ray photons either
into a visible image or into another form which can be made into a
visible image by further transformations.
"Inherent filtration" means the filtration permanently in the
useful beam; it includes the effect of the x-ray tube window and
any permanent tube or source enclosure (see "Filter" and
Filtration").
"Interlock" means a device arranged or connected such that the
occurrence of an event or condition is required before a second
event or condition can occur or continue to occur.
"Kilovolts peak (kVp)" means the crest value, in kilovolts, of the
electric potential applied to the x-ray tube between the cathode
and anode of a pulsating electric potential generator.
"Lead equivalent" means the thickness of lead affording the same
attenuation, under specified conditions, as the material in
question.
"Leakage radiation" means all radiation emanating from the
diagnostic source assembly except for:
The useful beam; and
The radiation produced when the exposure switch or timer is
not activated.
"Leakage technique factors" means the technique factors used to
measure leakage radiation from the diagnostic source assembly.
They are defined as follows:
For capacitor energy storage equipment, the maximum-rated
peak tube potential and the maximum-rated number of
exposures in an hour for operation at the maximum-rated peak
tube potential with the quantity of charge per exposure
being 10 millicoulombs, i.e. 10 milliampere seconds, or the
minimum obtainable from the unit, whichever is larger.
For field emission equipment rated for pulsed operation, the
maximum-rated peak tube potential and the maximum-rated
number of x-ray pulses in an hour for operation at the
maximum-rated peak tube potential.
For all other equipment, the maximum-rated peak tube
potential and the maximum-rated continuous tube current for
the maximum-rated peak tube potential.
"Light field" means that area of the intersection of the light
beam from the beam-limiting device and any one of the sets of
planes parallel to and including the plane of the image receptor.
The edge of the light field is defined as the locus of points at
which the illumination is 25 percent of that at the center of the
light field.
"Mammography" means radiography of the breast for the purpose of
enabling a physician to determine the presence, size, location and
extent of cancerous or potentially cancerous tissue in the breast.
"Mammography dosimetry test phantom" means a phantom for
determining the mean glandular breast dose. For automatic
exposure control mammography systems it shall be any phantom
material that is equivalent to a nominal 4.5 centimeter compressed
breast of average density (i.e., 50 percent adipose and 50 percent
glandular tissue).
"Mammography System" means an x-ray system that is used to perform
mammography.
"Medical radiographer" means a person other than a licensed
practitioner, accredited in accordance with the provisions of 32
Ill. Adm. Code 401, or an individual exempt from the provisions of
32 Ill. Adm. Code 401, who performs medical radiation procedures
and applies x-radiation, to any part of the human body, for
diagnostic purposes while under the supervision of a licensed
practitioner.
"Mobile equipment" (see "X-ray equipment").
"Non-certified system" means an x-ray system which is not subject
to regulations promulgated under Public Law 90-602, the Radiation
Control for Health and Safety Act of 1968 (see "Certified
system").
"Personnel monitoring" means the determination of radiation
exposure to a person. Devices used for this purpose may include,
but are not limited to, film badges, pocket dosimeters, and
thermoluminescent dosimeters worn by the individual.
"Phototimer" means a method for controlling radiation exposures to
image receptors by the amount of radiation which reaches a radia-
ion monitoring device(s). The radiation monitoring device(s) is
part of an electronic circuit which controls the duration of time
the tube is activated (see "Automatic exposure control").
Portable equipment" (see "X-ray equipment").
"Position indicating device" means a device on intraoral dental
x-ray equipment used to indicate the beam position and to
establish a definite source-skin distance.
"Positive beam limitation" means a beam-limiting device which
will, at the source-image receptor distance for which the device
is designed, either cause automatic adjustment of the x-ray field
in the plane of the image receptor to the image receptor size
within 5 seconds after insertion of the image receptor or, if
adjustment is accomplished automatically in a time interval
greater than 5 seconds or is manual, prevent production of x-rays
until such adjustment is completed. For SIDs at which the device
is not intended to operate, the device prevents the production of
x-rays.
"Primary protective barrier" (see "Protective barrier").
"Protective apron" means an apron of radiation absorbing
materials, at least 0.25 mm lead equivalent, used to reduce
exposure from stray radiation (see "Stray radiation").
"Protective barrier" means a barrier of radiation absorbing
material(s) used to reduce radiation exposure. The types of
protective barriers are as follows:
"Primary protective barrier" means the material, excluding
filters, placed in the useful beam to reduce the radiation
exposure.
"Secondary protective barrier" means a barrier sufficient to
attenuate the stray radiation to the required degree (see
"Stray radiation").
"Protective glove" means a glove made of radiation absorbing
materials, at least 0.25 mm lead equivalent, used to reduce
exposure from stray radiation (see "Stray radiation").
"Qualified expert" means an individual who has demonstrated to the
satisfaction of the Department that he or she possesses the
knowledge and training to measure ionizing radiation, to evaluate
safety techniques, and to advise regarding radiation protection
needs. Satisfactory demonstration of such knowledge and training
should include certification by a nationally recognized
credentialing entity in the field of radiation protection.
"Radiation therapy simulation system" means a radiographic/
fluoroscopic x-ray system used exclusively for localizing the
volume to be exposed during radiation therapy and confirming the
position and size of the therapeutic irradiation field.
"Radiologist" means a physician or veterinarian who is either:
Certified by the American Board of Radiology in diagnostic
radiology or general radiology;
Certified by the American Osteopathic Board of Radiology;
Certified by the American Chiropractic Board of Radiology;
or
Certified by the American College of Veterinary Radiology;
or
Eligible for certification by any College or Board
identified above.
"Scatter radiation" means radiation that, during passage through
matter, has been deviated in direction.
"Secondary protective barrier" (see "Protective barrier").
"Shutter" means an adjustable beam-limiting or attenuating device,
usually made of lead, fixed to an x-ray tube housing to intercept
or collimate the useful beam (see "Beam-limiting device").
"SID" means source-image receptor distance (see "Source-image
receptor distance").
"Source" means the focal spot of the x-ray tube.
"Source-image receptor distance" means the distance from the
source to the center of the input surface of the image receptor.
"Source-skin distance (SSD)" means the distance measured along the
central ray from the center of the front surface of the x-ray
focal spot to the surface of the irradiated object.
"Special purpose x-ray system" means any radiographic x-ray system
which, by design, is limited to radiographic examination of a
specific anatomical region.
"Spot film" means a radiograph which is made during a fluoroscopic
examination to permanently record conditions which exist during
that fluoroscopic procedure.
"Stationary equipment" (see "X-ray equipment").
"Stray radiation" means the sum of leakage and scatter radiation.
"Technique factors" means the electrical potential (kilovolts),
current (milliamperes), exposure time parameters (seconds or
pulses) or a combination thereof, selectable at the control panel
of an x-ray system (see "Control panel").
"Useful beam" means the radiation which passes through the tube
housing port and the aperture of the beam-limiting device when the
exposure switch or timer is activated.
"X-ray equipment" means an x-ray system, sub-system, or component
thereof. Types of x-ray equipment are as follows:
"Mobile x-ray equipment" means x-ray equipment mounted on a
permanent base with wheels and/or casters for moving while
completely assembled.
"Portable x-ray equipment" means x-ray equipment designed to
be hand-carried.
"Stationary x-ray equipment" means x-ray equipment which is
installed in a fixed location.
"X-ray field" means, for diagnostic purposes, that area of the
intersection of the useful beam and any 1 of the set of planes
parallel to and including the plane of the image receptor. The
edge of the x-ray field is defined as the locus of points at which
the exposure is 25 percent of that at the center of the x-ray
field.
"X-ray system" means an assemblage of components for the
controlled production of x-rays. It includes minimally an x-ray
high-voltage generator, an x-ray control panel, an x-ray tube
housing assembly, a beam-limiting device, and the necessary
supporting structures. Additional components which function with
the system are considered integral parts of the system.
(Source: Amended at 15 Ill. Reg. 6180, effective April 16, 1991)
Section 360.30 General Requirements and Administrative Controls
The requirements in this Section apply to all uses of x-rays in veterinary
medicine and to all uses of x-rays in the Healing Arts including the use of
x-rays for both diagnostic and therapeutic purposes. Additional requirements
for all diagnostic x-ray systems are in Section 360.40 and specific equipment
application classes are contained in Sections 360.50 through 360.100. For
therapeutic x-ray systems also see Sections 360.110 and 360.120.
a) Registrant - The registrant shall:
1) Direct the operation of the x-ray system(s);
2) Register with the Department, in accordance with the
provisions of 32 Ill. Adm. Code 320, all x-ray equipment
which is used at the facility;
3) Register with the Department, in accordance with the
provisions of 32 Ill. Adm. Code 320, all portable or mobile
x-ray equipment used by the Registrant;
4) Submit an application for inspection of radiation machines
to the Department in accordance with 32 Ill. Adm. Code 410
and, if the inspection is performed by a qualified
nondepartment inspector, submit a copy of the radiation
inspection report to the Department;
5) Permit operation of the x-ray system(s) only by individuals
who are licensed in accordance with State law (See Section
360.10(a)), or who are accredited by the Department or are
exempt from such requirements in accordance with the
provisions of 32 Ill. Adm. Code 401;
6) Inform all individuals who work in activities pursuant to
the operator's registration of their rights in accordance
with the provisions of 32 Ill. Adm. Code 400; and
7) Maintain records showing the receipt, transfer, use,
storage, and disposal of all sources of radiation in
accordance with the provisions of 32 Ill. Adm. Code 310 and
320.
b) Shielding - Each installation shall be provided with such primary
barriers and/or secondary barriers as are necessary to assure
compliance with the provisions of 32 Ill. Adm. Code 340.1010,
340.1040 and 340.1050.
c) An x-ray system which does not meet the provisions of this Part
shall not be operated for diagnostic or therapeutic purposes if so
ordered by the Director.
d) If an x-ray system is identified as not being in compliance with
the provisions of this Part and if that system is accessible for
use, it shall be rendered inoperable (i.e. dismantle the x-ray
source from the source support assembly) if so ordered by the
Director.
e) Unauthorized Exposure - Individuals shall not be exposed to the
useful beam except for healing arts purposes and only when such
exposure has been authorized by a licensed practitioner of the
healing arts. This provision specifically prohibits deliberate
exposure for the following purposes:
1) Exposure of individuals for training, demonstration, or
other non-healing arts purposes.
2) Exposure of individuals for the purpose of "healing arts
screening" (see Section 360.20).
f) Personnel Monitoring and Reporting Requirements - All persons who
are associated with the operation of an x-ray system are subject
to the occupational exposure limits and the requirements for the
determination of the doses which are contained in 32 Ill. Adm.
Code 340.1010, 340.1020, 340.1040, 340.2010, and 340.2020 and the
reporting requirements as stated in 32 Ill. Adm. Code 340.4010
through 340.4080.
g) The registrant shall comply with the requirements of the
Department's rules entitled, Notices, Instructions and Reports to
Workers; Inspections, 32 Ill. Adm. Code 400.
h) Maintenance Records and Associated Information - The registrant
shall maintain, for a period of at least 3 inspection cycles (see
32 Ill. Adm. Code 410.60(d)), the following information for each
x-ray system for inspection by the Department:
1) Separate records of maintenance and modifications performed
on each x-ray system with the name(s) of the individual(s)
who performed such services and the date(s) performed.
2) A copy of all correspondence with the Department regarding
the registrant's x-ray program.
i) Staff Qualifications - The registrant shall maintain for review by
the Department:
1) A current staffing plan indicating the names of all
individuals responsible for operating x-ray equipment and
the scope of their duties at the facility.
2) Current certificates of accreditation (clear, legible copies
are acceptable), issued by the Department in accordance with
the provisions of 32 Ill. Adm. Code 401, for all individuals
who are required to be so accredited.
j) Radiation Safety Program - The registrant shall provide for annual
in-service training in radiation safety for individuals (excluding
licensed practitioners) that apply ionizing radiation at the
facility, to ensure their awareness of the registrant's radiation
safety practices and policies.
1) The in-service training must include the following topics:
A) Operating and emergency procedures for the radiation
machine(s);
B) Use of personnel and patient protective devices;
C) Procedures to minimize patient and personnel exposure,
as required by Section 360.40;
D) Use of personnel monitoring devices (if such devices
are used at the facility);
E) Film processing procedures; and
F) Prohibited uses of fluoroscopic machines (if such
machines are used at the facility), as described in
Section 360.40(j).
2) The registrant shall maintain for a period of at least 3
inspection cycles (see 32 Ill. Adm. Code 410.60(d)),
documentation, signed by persons who apply ionizing
radiation, that indicates the date and content of training
provided.
3) The registrant shall provide to each individual subject to
in-service training a written policy statement outlining the
registrant's radiation safety practices and policies
specified in subsection (j)(1) above.
(Source: Amended at 15 Ill. Reg. 6180, effective April 16, 1991)
Section 360.40 General Equipment and Operation Requirements for Diagnostic
X-ray Systems
The requirements of this Section apply to all diagnostic x-ray systems.
Additional requirements for specific equipment application classes are in
Sections 360.50 through 360.100.
a) Half-Value Layer - The half-value layer of the useful beam for a
given x-ray tube potential shall not be less than the values shown
in Table B of this Part. If it is necessary to determine a half-
value layer at an x-ray tube potential which is not listed in
Table B, linear interpolation or extrapolation may be utilized to
determine the appropriate value.
b) Beam-On Indicators
1) The control panel shall include a device (usually a
milliammeter or labeled indicator lamp) which will give
positive indication of the production of x-rays whenever the
x-ray tube is energized.
2) In addition, on certified systems, a signal audible to the
operator shall indicate that the exposure has terminated.
c) Mechanical Support of Tube Head - The tube housing assembly
supports shall be adjusted such that the tube housing assembly
will remain stable during an exposure unless tube housing movement
is a designed function of the x-ray system.
d) Diagnostic Source Assembly Leakage Radiation Limits - The leakage
radiation measured at a distance of 1 meter from the source shall
not exceed 100 milliroentgens in 1 hour when the tube is operated
at its leakage technique factors.
e) Exposure Switch - The exposure switch shall be a dead-man switch.
f) Patient or Film Support - When a patient or film must be provided
with auxiliary support during a radiation exposure:
1) No person shall be used routinely to hold film or patients;
and
2) Unless the procedure precludes their use, mechanical holding
devices shall be used to restrain patients. For example,
mechanical holding devices could not be used if the devices
would preclude clear visualization of the tissue being
examined.
AGENCY NOTE: The radiation dose received by radiation
workers, patients, and the general public can be reduced if
mechanical patient and film support devices are used for
radiographic and fluoroscopic procedures. In the event that
an individual must be used in lieu of mechanical patient or
film support devices to hold patients or films, every effort
should be made to limit the individual's exposure to
radiation. This can be accomplished by not assigning to a
single individual the task of supporting patients and films
during radiographic and fluoroscopic examinations. Rather,
a number of individuals may be rotated through the
assignment, thereby reducing the radiation exposure to one
individual.
g) Personnel Protection -
1) Except for patients who cannot be moved out of the room,
only the staff and ancillary personnel required for the
medical procedure or training shall be in the room during
the radiographic/fluoroscopic exposure.
2) Individuals who must be in the room with the patient being
radiographed or fluoroscoped shall be positioned such that
no part of the individual's body will be exposed to:
A) The useful beam unless protected by 0.5 millimeter
lead equivalent apparel or device, and
B) Stray radiation unless protected by 0.25 millimeter
lead equivalent apparel or device.
AGENCY NOTE: If apparel is used, it should cover as
much of the individual's trunk and upper leg surface
areas as possible. Apparel that protects both
posterior and anterior surfaces is recommended. If a
device, e.g., protective screen/barrier, is used in
lieu of protective apparel, the device should be of
such a width and height to afford protection as would
be provided if apparel was worn.
h) Technique Guides - In the vicinity of each radiographic x-ray
system's control panel, a technique guide shall be provided which
specifies for routine examinations performed with that system, the
following information:
AGENCY NOTE: This requirement is applicable to both dental
intraoral and extraoral radiographic systems.
1) Patient's anatomical size versus technique factors to be
utilized,
2) Type and size of the film or film-screen combination to be
used, and
3) SID to be used.
4) For automatic exposure control (AEC) systems (i.e., systems
employing photo-multiplier tubes or ionization chambers to
terminate the x-ray exposure) with selectable exposure
detectors and density settings, the technique guide shall
also specify the appropriate exposure detector(s) and
density setting to be utilized for each radiographic
examination listed.
5) For AEC systems, the technique guide shall specify the
requirements of subsections (h)(1) through (3) above to be
followed if operated in a non-automatic mode.
i) Patient Exposure Criteria - Procedures and auxiliary equipment
designed to minimize patient and personnel exposure commensurate
with needed diagnostic information shall be used.
AGENCY NOTE: It is the intent of subsection (i) to provide for
the optimum optical density on the film while minimizing patient
exposure. The kVp and SSD employed in radiographic examinations
should be as great as practical and consistent with the diagnostic
objectives of the study. The x-ray equipment should permit use of
the optimum kVp that will reduce the doses to the patient based on
the required optical density of the film. The milliamperage
should be high enough to permit as short an exposure time as is
necessary to limit the effects of motion, which would result in
the loss of the radiograph's usefulness. In addition, x-ray
films, intensifying screens, and other image recording devices
should be as sensitive as is consistent with the requirements of
the examination. Non-screen films should not be used unless
absolutely necessary for a specific examination.
j) Prohibited Use - Fluoroscopy shall not be used as a substitute for
radiography or in lieu of proper anatomical positioning/centering
procedures prior to radiographic studies (see 32 Ill. Adm. Code
310.100 for additional prohibited uses).
k) X-ray Film Processing Systems-
1) Manual film processing systems shall be monitored by the
registrant to assure:
A) The use of a dedicated darkroom timer with an
adjustable preset function. The timer shall be used
to adjust film processing time according to solution
temperature.
B) The use of a dedicated darkroom thermometer. The
thermometer shall be used to adjust the film
processing time according to solution temperature.
C) The use of a film processing guide. The guide shall
contain, at a minimum, information regarding time(s)
and temperature(s) (as recommended by the processing
chemical manufacturer) used by the registrant to
develop radiographs.
D) The frequency at which film processing chemicals are
changed. At a minimum, the interval as recommended by
the chemistry manufacturer shall be used.
E) The darkroom safe light illumination is adequate for
the film speed(s) and the darkroom operating
procedures used to prevent fogging of unprocessed
film.
2) Automated film processing shall be monitored by the
registrant to assure that:
A) The temperature of film processing chemicals is
appropriate for the type of film(s) being processed at
the film transport speed selected.
B) The film processing chemicals used and their
replenishing rate (if applicable) are appropriate for
the film transport speed selected.
C) The darkroom safe light illumination is adequate for
the film speed(s) and the darkroom operating
procedures used (to prevent fogging of unprocessed
film).
l) Gonadal Shielding - Except for cases in which it would interfere
with the diagnostic procedure, gonadal shielding of not less than
0.50 millimeters of lead equivalent shall be used for patients
(who have not passed the reproductive age) during those
radiographic procedures in which the gonads are in the useful
beam.
AGENCY NOTE: Protection of the embryo or fetus from radiation
exposure during radiological examination or treatment of a woman
of childbearing age (potentially pregnant) should be given special
consideration. However, in practice, medical needs should be the
primary factors in deciding when to administer the examination.
(Source: Amended at 15 Ill. Reg. 6180, effective April 16, 1991)
Section 360.50 Fluoroscopic Systems
In addition to the provisions of Sections 360.10, 360.30 and 360.40, the
requirements of this Section apply to x-ray equipment and associated
facilities used for fluoroscopy.
a) Beam Limitation - The x-ray field shall, whenever possible, be
limited by adjustable shutters. In addition:
1) For x-ray equipment with adjustable shutters, the
mechanism(s) (manual/automatic mode selector(s)) provided
for activating and positioning the shutters shall function
properly. This requirement applies to shutters used in both
fluoroscopic and spot filming procedures.
2) For fluoroscopic equipment without image intensifiers, the
x-ray field shall not extend beyond the entire visible area
of the image receptor. This requirement applies to field
sizes for both fluoroscopic and spot filming procedures.
AGENCY NOTE: Visible area means that portion of the input
surface of the image receptor over which incident x-ray
photons are producing an image visible to the fluoroscopist.
3) For fluoroscopic equipment with image intensifiers, neither
the length nor the width of the x-ray field in the plane of
the image receptor shall exceed that of the visible area of
the image receptor by more than 3 percent of the SID. The
sum of the excess length and the excess width shall be no
greater than 4 percent of the SID. This requirement applies
to field sizes for both fluoroscopic and spot filming
procedures.
AGENCY NOTE: Visible area means that portion of the input
surface of the image receptor over which incident x-ray
photons are producing an image visible to the fluoroscopist.
b) Timer - A manual reset, cumulative timing device shall be used
which will either indicate elapsed on-time by an audible signal or
turn off the system when the total exposure time exceeds a
predetermined limit not exceeding 5 minutes in 1 or a series of
exposures.
c) Primary Barrier/Interlock - These devices shall function so that:
1) The entire cross section of the useful beam is intercepted
by the primary protective barrier of the fluoroscopic image
assembly at any SID; and
2) The fluoroscopic tube is interlocked to prevent the unit
from producing x-rays unless the primary barrier is in
position to intercept the useful beam, as specified in
subsection (c)(1) above, at all times.
d) Source-Skin Distance - The SSD shall not be less than:
1) 38 centimeters (15 inches) on stationary fluoroscopes which
are defined as certified systems,
2) 35.5 centimeters (14 inches) on stationary fluoroscopes
which are defined as non-certified systems,
3) 30 centimeters (12 inches) on all mobile fluoroscopes,
4) 20 centimeters (8 inches) for image-intensified fluoroscopes
used for a specific surgical application.
e) Entrance Exposure Rate (Non-Certified Systems) - Non-certified
fluoroscopic systems shall not be operable at any combination of
tube potential and current which will result in an exposure rate
in excess of 10 Roentgens per minute at the point where the center
of the useful beam enters the patient.
f) Entrance Exposure Rate (Certified Systems) -
1) Certified Systems With Automatic Exposure Rate Control -
Fluoroscopic systems which are provided with automatic
exposure rate control shall not be operable at any
combination of tube potential and current which will result
in an exposure rate in excess of 10 Roentgens per minute at
the point where the center of the useful beam enters the
patient, except:
A) During recording of fluoroscopic images; or
B) When an optional high level control is provided. (See
subsection (f)(3) below.)
2) Certified Systems Without Automatic Exposure Rate Control -
Fluoroscopic systems which are not provided with automatic
exposure rate control shall not be operable at any
combination of tube potential and current which will result
in an exposure rate in excess of 5 Roentgens per minute at
the point where the center of the useful beam enters the
patient, except:
A) During recording of fluoroscopic images; or
B) When an optional high level control is activated.
(See subsection (f)(3) below.)
3) When provided with optional high level control, the
equipment shall not be operable at any combination of the
tube potential and current which will result in an exposure
rate in excess of 5 Roentgens per minute at the point where
the center of the useful beam enters the patient unless the
high level control is activated.
A) Separate means of activation of high level controls
shall be required. The high level control shall only
be operable when continuous manual activation is
provided by the operator.
B) A continuous signal audible to the fluoroscopist shall
indicate that the high level control is being
employed.
4) Compliance with the requirements of subsections (e) and
(f)(1), (2) and (3) above shall be determined as follows:
A) For systems employing automatic exposure rate control,
material having an equivalency of at least 0.317 cm
(1/8 inch) of lead shall be placed in the primary beam
between the image receptor and the radiation measuring
device. The lead or equivalent material shall be
positioned to ensure that the entire primary beam is
blocked and the radiation measuring device is
positioned in accordance with the appropriate
measurement protocol outlined in this subsection.
B) If the source is below the table, the exposure rate
shall be measured 1 centimeter above the tabletop or
cradle.
AGENCY NOTE: The fluoroscopic exposure rate may be
measured at a reference point, in the central ray of
the primary beam, other than specified in this
subsection. However, compliance shall be determined
by calculating the exposure rate at the point
specified in this subsection.
C) If the source is above the table, the exposure rate
shall be measured at 30 centimeters (12 inches) above
the tabletop with the end of the beam-limiting device
or spacer positioned as closely as possible to the
point of measurement.
AGENCY NOTE: The fluoroscopic exposure rate may be
measured at a reference point, in the central ray of
the primary beam, other than specified in this
subsection. However, compliance shall be determined
by calculating the exposure rate at the point
specified in this subsection.
D) For a fixed SID C-arm type of fluoroscope, the
exposure rate shall be measured 30 centimeters (12
inches) from the input surface of the fluoroscopic
imaging assembly.
AGENCY NOTE: The fluoroscopic exposure rate may be
measured at a reference point, in the central ray of
the primary beam, other than specified in this
subsection. However, compliance shall be determined
by calculating the exposure rate at the point
specified in this subsection.
E) For a variable SID C-arm type of fluoroscope, the
exposure rate shall be measured 30 centimeters (12
inches) from the input surface of the fluoroscopic
imaging assembly with the end of the beam-limiting
device or spacer positioned as close as possible to
the point of measurement.
AGENCY NOTE: The fluoroscopic exposure rate may be
measured at a reference point, in the central ray of
the primary beam, other than specified in this
subsection. However, compliance shall be determined
by calculating the exposure rate at the point
specified in this subsection.
F) For a lateral type fluoroscope, the exposure rate
shall be measured on the central axis of the primary
beam at a point 15 centimeters (6 inches) from the
centerline of the x-ray table and in the direction of
the x-ray source with the end of the beam-limiting
device or spacer positioned as closely as possible to
the point of measurement. If the tabletop is movable,
it shall be positioned as closely as possible to the
lateral x-ray source, with the end of the beam-
limiting device or spacer no closer than 15
centimeters to the centerline of the x-ray table.
AGENCY NOTE: The fluoroscopic exposure rate may be
measured at a reference point, in the central ray of
the primary beam, other than specified in this
subsection. However, compliance shall be determined
by calculating the exposure rate at the point
specified in this subsection.
AGENCY NOTE: A lateral type fluoroscope is a
fluoroscope that cannot be rotated so that the source
or the fluoroscopic imaging assembly can be positioned
below the fluoroscopic table or cradle.
g) Screen Shielding - For systems without image intensifiers, the
fluoroscopic screen shall be covered with transparent protective
material having a lead equivalency of at least 1.5 millimeters for
equipment capable of operating up to 100 kVp, at least 1.8
millimeters for equipment whose maximum operating potential is
greater than 100 kVp and less than 125 kVp, and at least 2.0
millimeters for equipment whose maximum operating potential is 125
kVp or greater.
h) Staff and Ancillary Personnel Protection - The fluoroscopist,
assistants and observers allowed in the examining room shall be
protected from scatter radiation by protective aprons of not less
than 0.25 millimeters lead equivalent or whole body protective
barriers.
i) Additional Shielding - A shield of at least 0.25 millimeters lead
equivalent, such as overlapping protective drapes or hinged or
sliding panels, should be provided to intercept scatter radiation
which would otherwise reach the fluoroscopist and others near the
machine. This shielding shall not be a substitute for the wearing
of a protective apron (0.25 mm lead equivalent for protection
against scattered radiation).
j) Mobile Fluoroscopes - In addition to the other requirements of
this Section, mobile fluoroscopes shall provide intensified
imaging.
k) Radiation Therapy Simulation Systems - Radiation therapy
simulation systems shall be exempt from the requirements of
subsections (a), (b), (e) and (f) above provided that:
1) Such systems are designed and used in such a manner that no
individual other than the patient is in the x-ray room
during periods of time when the system is producing x-rays;
and
2) Such systems that do not meet the requirements of subsection
(b) above are provided with a means of indicating the
cumulative time that an individual patient has been exposed
to x-rays. Procedures shall require in such cases that the
timer be reset between examinations.
l) Operator Restrictions - No person shall intentionally administer
radiation to a human being with a fluoroscopic radiation machine
unless such person is licensed to practice a treatment of human
ailments under the Medical Practice Act of 1987, the Illinois
Dental Practice Act, the Podiatric Medical Practice Act of 1987,
and the Veterinary Medicine and Surgery Practice Act of 1983,
except an accredited medical radiographer may operate a
fluoroscope for static functions when interpretation of the
results is not required and only under the direct supervision of a
radiologist who is physically present.
(Source: Amended at 13 Ill. Reg. 803, effective April 1, 1989)
Section 360.60 Stationary Radiographic Systems Other Than Fluoroscopic,
Dental Intraoral, Veterinary, or Systems Used Solely For Mammography
In addition to the provisions of Sections 360.10, 360.30 and 360.40, the
requirements of this Section apply to x-ray equipment and associated
facilities used for radiography with stationary radiographic systems other
than fluoroscopic, dental intraoral, veterinary medical systems, or systems
used solely for mammography.
a) Beam Limitation - The useful beam shall be limited to the area of
clinical interest. The size of the image receptor utilized for
each radiographic projection shall be consistent with the
objectives of the examination.
1) Stationary General Purpose X-ray Systems - Means shall be
provided to limit the x-ray field in the plane of the image
receptor so that such field does not exceed each dimension
of the image receptor by more than 2 percent of the SID when
the axis of the x-ray beam is perpendicular to the plane of
the image receptor.
A) Variable X-Ray Field Limitation - There shall be
provided a means for stepless adjustment of the size
of the x-ray field.
B) Visual Indication of Field Size - Means shall be
provided for visually defining the perimeter of the x-
ray field. The total misalignment of the edges of the
visually defined field, with respect to the edges of
the x-ray field, shall not exceed 2 percent of the
distance from the source to the center of the visually
defined field when the surface upon which it appears
is perpendicular to the axis of the x-ray beam.
C) Numerical Indication of Field Size -
i) The beam-limiting device shall numerically
indicate the x-ray field size in the plane of
the image receptor to which it is adjusted.
ii) The x-ray field dimensions shall be specified in
inches and/or centimeters, and shall be such
that aperture adjustments result in x-ray field
dimensions in the plane of the image receptor
that do not differ from the numerical indicated
dimensions by more than + or - 2 percent of the
SID when the beam axis is perpendicular to the
plane of the image receptor.
iii) The beam-limiting device shall be provided with
SID scales that reflect the actual SID(s) used
for radiographic procedures.
D) SID Indication -
i) Means shall be provided to indicate the SID.
ii) SIDs shall be indicated in inches and/or
centimeters and the measured SID shall
correspond to the indicated value to within 2
percent.
E) X-Ray Field/Image Receptor Alignment - Means shall be
provided to:
i) Indicate when the axis of the x-ray field is
perpendicular to the plane of the image
receptor; and
ii) Align the center of the x-ray field with respect
to the center of the image receptor to within 2
percent of the SID.
F) Additional Requirements for Systems Equipped with
Positive Beam Limitation -
i) The x-ray field size in the plane of the image
receptor, whether automatically or manually
adjusted, shall be such that neither the length
nor the width of the x-ray field differs from
that of the image receptor by greater than 3
percent of the SID and that the sum of the
length and width differences without regard to
sign be no greater than 4 percent of the SID
when the equipment indicates that the beam axis
is perpendicular to the plane of the image
receptor.
ii) The radiographic system shall be capable of
operation, at the discretion of the operator,
such that the field size at the image receptor
can be adjusted to a size smaller than the image
receptor. The minimum field size at a distance
of 100 centimeters (40 inches) shall be equal to
or less than 5 centimeters by 5 centimeters (2
inches by 2 inches). Return to positive beam
limitation shall occur upon a change in image
receptor.
iii) Positive beam limitation may be bypassed when
radiography is conducted which does not use the
cassette tray or permanently mounted vertical
cassette holder, or when either the beam axis or
table angulation is not within 10 degrees of the
horizontal or vertical during any part of the
exposure, or during stereoscopic radiography.
If the bypass mode is provided, return to
positive beam limitation shall be automatic.
iv) A capability may be provided for overriding
positive beam limitation in the event of system
failure or to perform special procedures which
cannot be performed in the positive mode. If so
provided, a key shall be required to override
the positive mode. It shall be impossible to
remove the key while the positive mode is
overridden.
2) Special Purpose X-Ray Systems -
A) SID Indication -
i) Means shall be provided to indicate the SID.
ii) SIDs shall be indicated in inches and/or
centimeters and the measured SID shall
correspond to the indicated value to within 2
percent.
B) Means shall be provided to limit the x-ray field in
the plane of the image receptor so that such field
does not exceed each dimension of the image receptor
by more than 2 percent of the SID when the axis of the
x-ray beam is perpendicular to the plane of the image
receptor.
C) Means shall be provided to align the center of the x-
ray field with the center of the image receptor to
within 2 percent of the SID.
D) The requirements of subsection (a)(2)(B) above may be
met:
i) With a system that meets the requirements
specified in subsection (a)(1) above; or
ii) With an assortment of removable, fixed-aperture,
beam-limiting devices sufficient to meet the
requirement for each combination of image
receptor size and SID for which the unit is
used, with each such device having permanent,
clearly legible markings, in inches and/or
centimeters, to indicate the image receptor size
and SID for which it is designed; or
iii) With a beam-limiting device having multiple
fixed apertures sufficient to meet the
requirement for each combination of image
receptor size and SID for which the unit is
used. Permanent, clearly legible markings, in
inches and/or centimeters, shall indicate the
image receptor size and SID for which each
aperture is designed and shall indicate which
aperture is in position for use.
3) Single Purpose X-Ray Systems Designed for One Image Receptor
Size - Radiographic equipment designed for only 1 image
receptor size at a fixed SID shall be provided with means to
limit the x-ray field at the plane of the image receptor to
dimensions no greater than those of the image receptor when
the axis of the x-ray beam is perpendicular to the plane of
the image receptor.
b) Timers -
1) Means shall be provided to terminate the exposure at a
preset time interval, preset product of current and time,
preset number of pulses, or preset radiation exposure to the
image receptor. Also, it shall not be possible to make an
exposure when the timer is set to a zero or off position if
either position is provided.
2) In addition, for certified systems, termination of exposure
shall cause automatic resetting of the timer to its initial
setting or to zero.
c) Operator's Control Station - Stationary protective barriers shall
be provided for the x-ray operator.
d) Exposure Switch Arrangement - The exposure switch shall be
arranged so that it cannot be operated by a person outside a
stationary protective barrier.
e) Ancillary Personnel Protection - Individuals other than the
patient whose presence is required in the radiographic room during
an x-ray examination shall be protected from scatter radiation by
protective aprons of not less than 0.25 millimeters lead
equivalent or whole body protective barriers.
f) Medical Radiographic Exposure Limits - The exposure measured at
the table top for the technique used for an average adult patient
for routine medical radiography will be the following: (See
Appendix A for measurement protocol).
1) "Abdomen Anterior Posterior (A.P.) View" exposure shall not
exceed 500 milliroentgens per radiograph.
2) "Lumbar Spine Lateral View" exposure shall not exceed 1400
milliroentgens per radiograph.
3) "Cervical Spine A.P. View" exposure shall not exceed 150
milliroentgens per radiograph.
4) "Skull Posterior Anterior (P.A.) View" exposure shall not
exceed 400 milliroentgens per radiograph.
AGENCY NOTE: These exposures are maximums. With careful
selection of technique factors, adjustment of film
processing systems, and choice of film and film screen
combinations, patient exposures can be further reduced. For
example, the following patient exposures should not be
exceeded for each of the exams listed: "Abdomen A.P. View"
exposure should not exceed 350 milliroentgens per
radiograph; "Lumbar Spine Lateral View" exposure should not
exceed 1,000 milliroentgens per radiograph; "Cervical Spine
A.P. View" exposure should not exceed 100 milliroentgens per
radiograph; and "Skull P.A. View" exposure should not exceed
200 milliroentgens per radiograph.
(Source: Amended at 15 Ill. Reg. 6180, effective April 16, 1991)
Section 360.70 Mobile/Portable Radiographic Systems Other Than Systems Used
Solely For Mammography
In addition to the provisions of Sections 360.10, 360.30 and 360.40, the
requirements of this Section apply to x-ray equipment and associated
facilities used for radiography with medical mobile/portable systems.
a) Beam Limitation - The useful beam shall be limited to the area of
clinical interest. The size of the image receptor used for each
radiographic projection shall be consistent with the objectives of
the examination.
1) Limitation Criteria - Means shall be provided to limit the
x-ray field in the plane of the image receptor so that the
field does not exceed each dimension of the image receptor
by more than 2 percent of the SID when the axis of the x-ray
beam is perpendicular to the plane of the image receptor.
Limitation of the x-ray field for certified x-ray systems
shall be accomplished by the means specified in Section
360.60(a)(1)(A) and (B). For non-certified x-ray systems,
the x-ray field shall be limited by the means specified in
either Section 360.60(a)(1)(A) and (B) or Section
360.60(a)(2)(D)(i) and (ii).
2) SID Indication -
A) Means shall be provided to indicate the SID.
B) SIDs shall be indicated in inches and/or centimeters
and the measured SID shall correspond to the indicated
value to within 2 percent.
b) Exposure Switch Arrangement -
1) The exposure control switch shall be arranged so that the
operator can stand at least 6 feet from the patient, the x-
ray tube, and well away from the useful beam.
2) All individuals operating mobile/portable x-ray systems
shall wear protective aprons of not less than 0.25
millimeters lead equivalent.
3) When a mobile/portable x-ray system is used in 1 location,
it shall be considered a stationary system subject to the
requirements specified in Section 360.60(c) and (d).
c) Source-Skin Distance -
1) Non-certified x-ray systems shall not be operable at a SSD
of less than 20 centimeters (8 inches).
2) Certified x-ray systems shall not be operable at a SSD of
less than 30 centimeters (12 inches).
d) Timers -
1) Means shall be provided to terminate the exposure at a
preset time interval, preset product of current and time,
preset number of pulses, or preset radiation exposure to the
image receptor. Also, it shall not be possible to make an
exposure when the timer is set to a zero or off position if
either position is provided.
2) In addition, for certified systems, termination of exposure
shall cause automatic resetting of the timer to its initial
setting or to zero.
e) Radiation from Capacitor Energy Storage X-ray Equipment in Standby
Status - Radiation emitted from the x-ray tube when the exposure
switch or timer is not activated shall not exceed a rate of 2
milliroentgens per hour at 5 centimeters (2 inches) from any
accessible surface of the diagnostic source assembly, with the
beam-limiting device fully open.
f) Ancillary Personnel Protection - Individuals other than the
patient whose presence is required in the radiographic room during
an x-ray examination shall be protected from scatter radiation by
protective aprons of not less than 0.25 millimeters lead
equivalent or whole body protective barriers.
g) Medical radiographic Exposure Limits - Criteria specified in
Section 360.60(f) apply.
(Source: Amended at 15 Ill. Reg. 6180, effective April 16, 1991)
Section 360.71 Requirements for Facilities Performing Mammography
In addition to the provisions of Sections 360.30, 360.40 and 32 Ill. Adm. Code
400 and 401, the requirements of this Section apply to mammography systems and
associated facilities used for mammography.
a) Physician Supervision - Mammography operations and procedures
shall be under the supervision of a physician licensed under the
Medical Practice Act of 1987 (Ill. Rev. Stat. 1989, ch. 111, par.
4400) to practice medicine in all of its branches.
AGENCY NOTE: The individual interpreting clinical images of the
breast should be a radiologist trained in the imaging modality
being used and should be certified or eligible for certification
by either the American Board of Radiology in diagnostic radiology
or general radiology or the American Osteopathic Board of
Radiology. A facility performing mammography should have a
program that is accredited by the American College of Radiology or
the Illinois Radiological Society or have a program that is
comparable.
b) Screen-Film Mammography - Screen-film mammography shall only be
performed with a special purpose radiation machine specifically
designed for mammography procedures.
c) Xeromammography - Xeromammography shall only be performed with a
radiation machine that has been specifically designed for or
modified to perform xeromammography.
d) Beam Limitation -
1) Means shall be provided to limit the useful beam so that the
x-ray field at the plane of the image receptor does not
extend beyond any edge of the image receptor at any
designated source to image receptor distance (SID).
However, the x-ray field may extend beyond the edge of the
image receptor designed to be adjacent to the chest wall
provided it does not extend beyond this edge by more than 2
percent of the SID.
2) The requirement of subsection (d)(1) above shall be met with
a system that performs as prescribed in either Section
360.60(a)(1) or Section 360.60(a)(2)(D)(ii).
e) Beam Limiting Device Labeling -
1) If beam limitation is met with a device as prescribed in
Section 360.60(a)(2)(D)(ii), such device shall have
permanent clearly legible markings in inches and/or
centimeters indicating the image receptor size and SID for
which each device is designed.
2) If the radiation machine is capable of using variable SIDs,
the SID indication specified in subsection (e)(1) above
shall be the maximum SID for which the beam limiting device
is designed.
f) Exposure Switch Arrangement -
1) Stationary Mammography Systems - For mammography systems
consisting of stationary x-ray equipment, the criteria
specified in Section 360.60(d) shall apply.
2) Mobile and Portable Mammography Systems - For mammography
systems consisting of mobile and portable x-ray equipment,
the criteria specified in either Section 360.60(d) or
Section 360.70(b)(1) shall apply.
g) Operator Shielding -
1) Stationary Mammography Systems - For mammography systems
consisting of stationary x-ray equipment, the criteria
specified in Section 360.60(c) shall apply.
2) Mobile and Portable Mammography Systems - For mammography
systems consisting of mobile and portable x-ray equipment,
the criteria specified in either Section 360.60(c) or
Section 360.70(b)(2) shall apply.
3) Mobile and Portable X-Ray Equipment Used in Only One
Location - When mobile or portable x-ray equipment is used
in only one location, it shall be considered a stationary
system and shall be subject to the requirements specified in
Sections 360.60(c) and (d).
h) Timers - The criteria specified in Section 360.60(b) shall apply.
i) SID Indicator - For radiation machines capable of operating at
variable SIDs, the criteria specified in Section 360.60(a)(1)(D)
shall apply.
k) Backup Timer - Radiation systems with automatic exposure control
(AEC) shall incorporate a backup timer to terminate the radiation
exposure in the event of AEC failure.
l) SSD - Except with respect to magnification for mammography
projections, mammography systems shall satisfy the requirements of
Section 360.70(c).
m) Focal Spot Size - The nominal focal spot size, as specified by the
x-ray tube manufacturer, shall not exceed 0.7 millimeters.
n) Reproducibility of Exposures - For all systems, regardless of
whether they are equipped with AEC, the estimated coefficient of
variation of radiation exposures shall be no greater than 0.05 for
any specific combination of selected technique factors. It will
not be necessary to calculate the coefficient of variation if for
4 consecutive measurements taken within a time period of 1 hour
the difference between the highest and lowest exposures does not
exceed 10 percent. If there is a difference greater than 10
percent, 6 additional exposures shall be made and the coefficient
of variation shall be calculated.
AGENCY NOTE: "Coefficient of variation" means the ratio of the
standard deviation to the mean value of a population of
observations. It is calculated using the following equation:
where:
s = Estimated standard deviation of the population.
X = Mean value of observations in sample.
Xi = ith observation sampled.
n = Number of observations sampled.
o) Mammography Exam Dose Limits (See Appendix B for the required
measurement protocol.) - The mean glandular dose for one
craniocaudal view of a 1.8 inch (4.5 centimeter) compressed breast
(50 percent adipose/50 percent glandular) shall not exceed:
1) 100 millirads (1 milligray) for film/screen radiographs not
employing the use of grids,
2) 300 millirads (3 milligrays) for film/screen radiographs
employing the use of grids, or
3) 400 millirads (4 milligrays) for xerography.
AGENCY NOTE: A facility performing mammography should have
a Mammography Dosimetry Test phantom specifically designed
for breast imaging. This phantom should enable the
individual interpreting clinical images of the breast to
readily determine the x-ray system's ability to identify
masses, fibrils, and calcifications on a month to month
basis.
(Source: Added at 15 Ill. Reg. 6180, effective April 16, 1991)
Section 360.80 Photofluorographic Systems
In addition to the provisions of Sections 360.10, 360.30 and 360.40, the
requirements of this Section apply to x-ray equipment and associated
facilities used for photofluorography.
AGENCY NOTE: Photofluorography is frequently called mass miniature
radiography. This is the method usually employed in projects such as chest x-
rays for tuberculosis control. In this technique the image of a fluorescent
screen is recorded on film by means of a camera. The film used is of small
size. Some units use cut film 4 inches by 4 inches in size. More commonly,
roll film is used; the film is usually 70-mm wide, but may be 90 or 100-mm.
a) Beam Limitation - Photofluorographic systems shall be provided
with means to limit the x-ray field at the plane of the image
receptor to dimensions no greater than those of the image
receptor.
b) Operator Control Station - Criteria specified in Section 360.60(c)
shall apply.
c) Exposure Switch Arrangement - Criteria Specified in Section
360.60(d) shall apply.
d) Timers -
1) Means shall be provided to terminate the exposure at a
preset time interval, preset product of current and time,
preset number of pulses, or preset radiation exposure to the
image receptor. Also, it shall not be possible to make an
exposure when the timer is set to a zero or off position if
either position is provided.
2) In addition, for certified systems, termination of exposure
shall cause automatic resetting of the timer to its initial
setting or to zero.
e) Ancillary Personnel Protection - Other than the patient,
individuals whose presence is required in the radiographic room
during an x-ray examination shall be protected from scatter
radiation by protective aprons of not less than 0.25 millimeters
lead equivalent or whole body protective barriers.
f) Photofluorographic Exposure Limit - The exposure to an average
patient shall not exceed 200 milliroentgens per photofluorograph
(See Appendix A for measurement protocol).
AGENCY NOTE: The patient exposure for this procedure should not
exceed 100 milliroentgens per photofluorograph.
g) Medical Supervision - The supervising physician shall outline
responsibilities regarding the photofluorographic operating and
patient screening procedures. The procedures shall be submitted
to this Department in writing prior to utilization of the
equipment. Operating and patient screening procedures shall
include at a minimum the following:
1) Operator qualifications,
2) Operator supervision,
3) Methods of operating x-ray machines,
4) Patient age limit,
5) Frequency of exam,
6) Pregnancy cases, etc.
(Source: Amended at 13 Ill. Reg. 803, effective April 1, 1989)
Section 360.90 Intraoral Dental Radiographic Systems
In addition to the provisions of Sections 360.10, 360.30 and 360.40, the
requirements of this Section apply to x-ray equipment and associated
facilities used for intraoral dental radiography.
a) Beam Limitation - X-ray systems designed for use with an intraoral
image receptor shall be provided with means to limit the x-ray
field at the patient's face to the smallest area which is
clinically necessary. The x-ray field striking the patient's face
shall not exceed a circle 7.5 centimeters (3 inches) in diameter.
Even though the beam shall be containable within a circle 7.5
centimeters in diameter, it may be a rectangular configuration.
1) Beam limitation shall be accomplished by a position
indicating device that is operated and shielded. The device
shall provide the same degree of shielding as the tube
housing assembly.
2) The position indicating device shall provide a SSD of not
less than 18 centimeters (7 inches) for systems operated
above fifty (50) kVp or 10 centimeters (4 inches) for
systems operated at fifty (50) kVp or below.
b) Timers -
1) Means shall be provided to terminate the exposure at a
preset time interval, preset product of current and time,
preset number of pulses, or preset radiation exposure to the
image receptor. Also, it shall not be possible to make an
exposure when the timer is set to a zero or off position if
either position is provided.
2) In addition, for certified systems, termination of exposure
shall cause automatic resetting of the timer to its initial
setting or to zero.
c) Exposure Switch Arrangement/Operator Protection - The exposure
switch shall be arranged so that the operator can be at least 6
feet from the patient and well away from the useful beam during an
exposure.
AGENCY NOTE: The Department recommends that whenever practicable,
the x-ray operator stand behind a protective barrier or be
provided with a protective apron of not less than 0.25 millimeters
lead equivalent.
d) Ancillary Personnel Protection - Other than the operator and the
patient, individuals whose presence is required in the room during
an x-ray examination shall be protected from stray radiation by
protective aprons of not less than 0.25 millimeters lead
equivalent or a protective barrier.
e) Dental Radiographic Exposure Limits (Single Film) - The entrance
exposure to an adult patient for a routine intraoral bitewing exam
shall not exceed the maximum limits specified in Table C.
(Source: Amended at 13 Ill. Reg. 803, effective April 1, 1989)
Section 360.100 Veterinary Radiographic Systems
In addition to the provisions of Sections 360.10, 360.30 and 360.40, the
requirements of this Section apply to x-ray equipment and associated
facilities used for radiography with veterinary systems.
a) Beam Limitation - The useful beam shall be limited to the area of
clinical interest. The size of the image receptor used for each
radiographic projection shall be consistent with the objectives of
the examination.
1) Limitation Criteria - Means shall be provided to limit the
x-ray field in the plane of the image receptor so that the
field does not exceed each dimension of the image receptor
by more than 2 percent of the SID when the axis of the x-ray
beam is perpendicular to the plane of the image receptor.
2) Means shall be provided to align the center of the x-ray
field with the center of the image receptor to within 2
percent of the SID.
3) The requirements of subsection (a)(1) above may be met with:
A) A system that meets the requirements specified in
Section 360.60(a)(1); or
B) An assortment of removable, fixed-aperture, beam-
limiting devices sufficient to meet the requirement
for each combination of image receptor size and SID
for which the unit is used, with each such device
having permanent, clearly legible markings in inches
and/or centimeters, to indicate the image receptor
size and SID for which it is designed; or
C) A beam-limiting device having multiple fixed apertures
sufficient to meet the requirement for each
combination of image receptor size and SID for which
the unit is used. Permanent, clearly legible
markings, in inches and/or centimeters, shall indicate
the image receptor size and SID for which each
aperture is designed and shall indicate which aperture
is in position for use.
4) SID Indication -
A) Means shall be provided to indicate the SID.
B) SIDs shall be indicated in inches and/or centimeters
and the measured SID shall correspond to the indicated
value to within 2 percent.
b) Exposure Switch Arrangement -
1) The exposure control switch shall be arranged so the
operator can be at least 6 feet from the patient, the x-ray
tube, and well away from the useful beam.
2) All individuals operating veterinary x-ray systems shall
wear protective aprons of not less than 0.25 millimeters
lead equivalent or shall be protected from scatter radiation
by a protective barrier.
c) Timers -
1) Means shall be provided to terminate the exposure at a
preset time interval, preset product of current and time,
preset number of pulses, or preset radiation exposure to the
image receptor. Also, it shall not be possible to make an
exposure when the timer is set to a zero or off position if
either position is provided.
2) In addition, for certified systems, termination of exposure
shall cause automatic resetting of the timer to its initial
setting or to zero.
d) Radiation From Capacitor Energy Storage X-ray Equipment in Standby
Status - Radiation emitted from the x-ray tube when the exposure
switch or timer is not activated shall not exceed a rate of 2
milliroentgens per hour at 5 centimeters from any accessible
surface of the diagnostic source assembly, with the beam-limiting
device fully open.
e) Ancillary Personnel Protection - Individuals whose presence is
required during an x-ray examination shall be protected from
scatter radiation by protective aprons or gowns of not less than
0.25 millimeters lead equivalent or whole body protective
barriers.
f) Veterinary Fluoroscopic Systems - All provisions of Section 360.50
apply except subsections (b) and (l).
(Source: Amended at 13 Ill. Reg. 803, effective April 1, 1989)
Section 360.110 Therapeutic X-Ray Installations
a) Equipment
1) Tube Housing -
A) The protective tube housing shall be of therapeutic-
type, except in the case of "Contact" X-Ray Therapy
(See Section 360.120(a)).
B) A therapeutic-type protective tube/target housing is
defined as follows:
i) For x-ray therapy equipment not capable of
operating at 500 kVp or above, the following
definition applies: An x-ray tube housing so
constructed that the leakage radiation at a
distance of one meter from the source does not
exceed one Roentgen in an hour when the tube is
operated at its maximum rated continuous current
for the maximum rated tube potential.
ii) For x-ray therapy equipment capable of operating
at 500 kVp or above, the following definition
applies: An x-ray tube housing so constructed
that the leakage radiation at a distance of one
meter from the source does not exceed either one
Roentgen in an hour or 0.1 percent of the useful
beam dose rate at one meter from the source,
whichever is the greater when the machine is
operated at its maximum rated continuous current
for the maximum rated accelerating potential.
iii) In either case, small areas of reduced
protection are acceptable provided the average
reading over any 100 square centimeters area at
one meter distance from the source does not
exceed the values given above.
2) Collimation - The useful beam shall be collimated by means
of cones, diaphragms or lead coverings to reduce the useful
beam striking a patient to the smallest area which is
clinically necessary.
3) Filtration - The filter system shall conform to recommended
practices as defined in the current National Council on
Radiation Protection Report No. 33, entitled "Medical X-Ray
and Gamma Ray Protection for Energies up to 10 MeV,
Equipment Design and Use".
4) Filtration Indicator - A filter indication system shall be
used on all therapy machines using changeable filters. It
shall be designed so as to permit easy recognition of any
added filter in place. It shall indicate, from the control
panel, the presence or absence of any filter.
5) Tube/Aperture Alignment - The x-ray tube shall be so mounted
that it cannot turn or slide with respect to the housing
aperture.
6) Tube Head Stability - Methods shall be provided to
immobilize the tube housing during stationary portal
treatment.
7) Preset Exposure Termination Device - A device (e.g. an
automatic timer, exposure meter or dose meter) shall be
provided to terminate the exposure after a preset time
interval or preset exposure or dose limit. Methods shall be
provided for the operator to terminate the exposure at any
time.
8) Shutter Position Indicator - Equipment utilizing shutters to
control the useful beam shall have a shutter position
indicator on the control panel.
9) Positive Indicator - The control panel shall include a
device (usually a milliammeter) which will give positive
indication of the production of x-rays whenever the x-ray
tube is energized.
10) Interlock - 150 kVp or Greater - A reliable interlock shall
be installed on each door of the therapeutic room. This
interlock shall be wired into the electrical circuit in such
a manner that when the door is opened, for any reason, the
x-ray exposure will automatically be terminated so that
irradiation can be resumed only by manually resetting the
controls on the control panel after the door is closed.
11) Door-Fastening Mechanism - If required, the door-fastening
mechanism shall be installed so that the door can be opened
from the inside in case of emergency.
12) Warning Lights - Treatment rooms to which access is possible
through more than one entrance shall be provided with
flashing warning lights in a readily observable position
near the outside of all access doors, which will indicate
when the useful beam is "on".
b) Operating Procedures.
1) All new facilities, and existing facilities not previously
surveyed, shall have a protection survey made by, or under
the direction of a qualified expert. This shall also be
done after any change in the facility which might produce a
radiation hazard. The expert shall report his findings in
writing to the person in charge of the facility and a copy
of this report shall be transmitted to the Department.
2) The facility shall be operated in compliance with any
limitations indicated by the protection survey required by
the Department.
3) When a patient must be held in position for radiation
therapy, mechanical supporting or restraining devices shall
be used whenever feasible.
4) Attendants - Below 120 kVp - No person, other than the
attending physician or his assistant, shall be in the
treatment room during exposure, except if in the opinion of
the physician such attendance in the room is clinically
necessary or desirable. If a person is required to hold or
support the patient, no portion of such person shall be in
the useful beam and such person shall be protected as much
as is practicable from scattered radiation. The exposure of
any person used for this purpose shall be monitored and a
record maintained.
5) Attendants - 120 kVp or Greater - No person except the
attending physician who works with ionizing radiation, shall
be in the treatment room during exposure.
6) Communication with Patient - The control panel shall be
arranged in such a manner that the operator can maintain
aural and visual communication with the patient. Both the
patient and the control panel shall be under observation of
the operator during the entire exposure.
7) The output of each therapeutic x-ray machine shall be
calibrated by, or under the direction of a qualified expert.
The calibration shall be repeated after any change in or
replacement of components of the x-ray output. Check
calibrations shall be made at least once a year thereafter
and be maintained by the registrant. Records of calibration
shall be posted at the controls and shall include the date
of calibration and the written signature of the qualified
expert.
c) Structural Shielding.
1) Primary protective barriers shall be provided for any area
that the useful beam may strike when using the largest
possible diaphragm opening. Such barriers should extend at
least one foot beyond the useful beam for any possible
orientation.*
2) Secondary protective barriers shall be provided for all
occupied areas exposed to leakage and scattered radiation.*
*Shall also conform with criteria outlined in NCRP Report
No. 49 entitled "Structural Shielding Design and Evaluation
for Medical Use of X-Ray and Gamma Rays of Energies Up to 10
MeV."
Section 360.120 Special Requirements for X-Ray Therapy Equipment Operated at
Potential of Fifty (50) kVp and Below
a) Equipment.
1) All provisions of Section 360.110(a) apply except
paragraphs(a)(10),(11) and (12), and except in the case of
"Contact" x-ray tubes, where the leakage radiation at the
surface of the housing shall not exceed 0.1 R/hr.
2) Preset Timer - Automatic timers shall be provided which will
permit accurate presetting and termination of exposures as
short as one second.
b) Operating Procedures.
1) In the therapeutic application of apparatus constructed with
beryllium or other low-filtration windows, the registrant
shall insure that the unfiltered radiation reaches only the
part intended and that the useful beam is blocked at all
time except when actually being used.
2) Machines having an output of more than 1,000 Roentgens per
minute at any accessible place shall not be left unattended
without the power being shut off at the main disconnect
switch in addition to the control panel switch.
3) If the tube must be hand-held during irradiation the
operator shall wear protective gloves and protective apron
no less than 0.5 millimeter lead equivalent.
c) Structural Shielding.
In general, additional structural barriers will not be required.
However, calculations of dose rates at critical positions beyond
walls, partitions, etc., shall be made to determine if additional
structural barriers will be required.
Section 360.APPENDIX A Medical Radiographic Exposure Limits
Measurement Protocol
The medical radiographic examinations specified in Section 360.60(f) are
examinations frequently taken at medical radiation installations.
The exposures measured using the "measurement protocol" are not actual
"entrance exposures" to patients but should be considered "reference
exposures" (patients are not involved in the measurement protocol).
a) An integrating exposure radiation measuring device is placed on
the radiographic table-top directly in the center of the useful
beam.
AGENCY NOTE: Applicable radiation measuring devices include but
are not limited to: Condenser - R meter, low energy dosimeter
(LED), integrating mode of a cutie-pie, thermoluminescent
dosimetry (TLD).
AGENCY NOTE: In the event a patient support table is not
utilized, (e.g., mobile/portable radiography) the measuring device
should be placed directly in the center of the useful beam on any
convenient support surface. The radiographic tube-to-measuring
device distance shall be identical to the source-to-image receptor
distance used during an actual patient exposure.
b) The radiographic tube is positioned identical to that used during
an actual patient exposure (usually 40 inches to bucky).
c) The exposure technique is set up as follows:
1) For non-phototimed x-ray systems, the exposure technique
used by the x-ray operator for an "average-sized" adult
patient is set up on the controls.
EXAMPLE: A.P. Abdomen (80 kVp, 100 mAs). The useful beam
is limited to the appropriate film size.
2) For phototimed x-ray systems, including photofluorographic
systems, the exposure technique used by the x-ray operator
for an "average sized" adult patient is set up on the
controls. An appropriate phantom (simulating body
attenuation) is placed in the useful beam between the
radiation measuring device and the radiographic table-top or
the surface of the photofluorographic screen assembly. The
useful beam is limited to the size of the phantom.
d) A radiographic exposure is made (without patient) and the reading
obtained from the radiation measuring device is recorded as a
representative radiation exposure for that specific examination to
determine compliance.
(Source: Amended at 13 Ill. Reg. 803, effective April 1, 1989)
Section 360.APPENDIX B Mammography Dose Limit
MEASUREMENT PROTOCOL
The technique factors used for performing a mammography examination shall not
permit the mean glandular absorbed dose to exceed the limits specified in
Section 360.71(o).
The mammography exam dose limits are based on an average compressed breast
value of 4.5 centimeters having an average density (i.e., 50 percent adipose
and 50 percent glandular). While other sizes and densities may be present in
the actual population of interest, this average compressed breast of 4.5
centimeters and density of 50 percent adipose and 50 percent glandular tissue
will suffice as a dose model reference within the accuracies needed to provide
safety to the general public.
a) Non-Automatic Exposure Control Systems - Perform the following
steps to determine the mean glandular dose to a nominal 4.5
centimeter compressed breast:
1) Determine the x-ray tube target material.
2) Identify the curve which represents a 4.5 centimeter
compressed breast thickness from the "Mammography Dose
Evaluation" graph (see Illustration B).
3) Measure and record the x-ray system's useful beam half-value
layer (HVL). (See Section 360.40(a).) Any compression
device normally in the useful beam during mammography
procedures shall be required to be placed between the x-ray
tube target and measuring device when determining the HVL.
The useful beam shall be collimated to a size encompassing
the detector.
AGENCY NOTE: Filters used for the HVL evaluation should be
placed as close to the target as possible. The HVL for
film/screen mammography should not exceed 0.4 millimeters of
aluminum equivalent and 1.6 millimeters of aluminum
equivalent for xerography.
4) Estimate the normalized rad per roentgen factor from the
"Mammography Dose Evaluation" graph (see Illustration B)
using the coordinates for a 4.5 centimeter compressed breast
thickness and the appropriate HVL.
Example: A radiation machine is provided with a
molybdenum target and its HVL is determined to
be 0.3. Therefore, for a 4.5 centimeter
compressed breast, the normalized rad per
roentgen factor would be 0.15.
5) Set the appropriate craniocaudal source to image receptor
distance (SID) for the image receptor system used.
6) Place a radiation measuring device in the useful beam so
that the center axis of the device is parallel to the breast
support assembly (BSA). The geometric center of the
measuring device shall be positioned so that it is centered
4.5 centimeters above the BSA, 2.54 centimeters (1 inch)
from the chest wall edge of the BSA and at the center line
of the BSA. (see Illustration A) The radiation measuring
device shall be an integrating type appropriate to the high
beam intensity and mammographic kilovoltage peak (kVp) used.
No part of the device's detector area shall be outside of
the useful beam.
7) Collimate the x-ray field to the size normally used.
8) Set the milliamperage (mA), kilovoltage peak (kVp) and
exposure time technique factors normally used for a nominal
4.5 centimeter compressed breast.
9) Position in the useful beam any compression apparatus
normally used.
10) Measure and record the exposure in air with the radiation
measuring device.
11) Calculate the mean glandular dose for a 4.5 centimeter
compressed breast by multiplying the measured exposure in
roentgens by the normalized rads per roentgen figure
established in subsection (a)(4) above.
Example: The rad (milligray) per roentgen figure of 0.15
established in subsection (a)(4) will be used.
The measured roentgen output (subsection (a)(10)
is determined to be 1.8 roentgens. Therefore,
the mean glandular dose would be 288 millirads
(2.88 milligrays). If the image receptor type
used was film/screen with grid, the system would
be in compliance with Section 360.71(o)(2).
b) Systems Equipped with AEC That Have A Means To Determine Exposure
Elapsed Time - Perform one of the following two procedures to
determine the mean glandular dose to a 4.5 centimeter compressed
breast for systems equipped with either a milliamp second (mAs)
meter or an exposure time indicator.
1) Mammography dosimetry test phantom procedure
A) Follow the procedures outlined in subsections (a)(1),
(2), (3), (4) and (5) above.
B) Place a mammography dosimetry test phantom (see the
definition for "Mammography dosimetry test phantom" in
Section 360.20) on the breast support assembly.
Center the phantom on the assembly to assure the
phantom is over the automatic exposure control
device(s).
C) Place a radiation measuring device in the useful beam
so the center axis of the device is parallel to the
breast support assembly (BSA). The geometric center
of the measuring device shall be positioned so that it
is centered 4.5 centimeters above the BSA, 2.54
centimeters (1 inch) from the chest wall edge of the
BSA and immediately adjacent to either side of the
breast dosimetry test phantom.
D) Collimate the x-ray field to the size normally used
and assure that the area covered by the useful beam
includes the breast dosimetry test phantom and the
detector area of the radiation measuring device.
E) Set the milliamperage (mA) and kilovoltage peak (kVp)
technique factors normally used for a nominal 4.5
centimeter compressed breast.
F) Position in the useful beam, any compression apparatus
normally used.
G) Make an exposure and record the exposure indicated by
the radiation measuring device.
H) Calculate the mean glandular dose for a 4.5 centimeter
compressed breast. (See subsection (a)(11) above.)
2) Mammography test procedure without a mammography dosimetry
test phantom.
A) Record for 30 consecutive days the patient
characteristics in terms of mAs, compressed breast
size and kVp per radiograph to determine an average.
All patients radiographed during the 30 day period
shall be included in the average. For the purpose of
this protocol, breast size measurements shall be
accurate to within 0.3 centimeters. The 4.5
centimeter compressed dimension is measured at a point
midway between the medial and lateral edges of the
breast and 1/2 the distance between the surface of the
chest wall and the base of the nipple.
B) Calculate the average mAs and kVp associated with a
nominal 4.5 centimeter compressed breast from the data
recorded. The calculation may be either arithmetic or
graphic.
AGENCY NOTE: A sample size of at least 30 will be
considered an acceptable sample size for the purpose
of determining the average mAs and kVp used for a
nominal 4.5 centimeter compressed breast. If the
sample size is less than 30, the graphic method of
determining the average mAs and kVp shall be used.
C) Turn off the automatic exposure control system and
set-up the x-ray system as specified in subsections
(a)(1), (2), (3), (4), (5) and (6) above.
D) Collimate the x-ray field to the size normally used
and assure that the area of the useful beam includes
the detector area of the radiation measuring device.
E) Set the mAs and kVp as would be used if the automatic
system was being used for a 4.5 centimeter compressed
breast (i.e., based on the average technique factors
calculated from subsection (b)(2)(B) above).
F) Position in the useful beam any compression apparatus
normally used.
G) Perform the exposure measurement and calculate the
mean glandular dose as specified in subsections
(a)(10) and (11) above.
c) Systems Equipped with AEC That Do Not Have A Means To Determine
Exposure Elapsed Time - Perform one of the following two
procedures to determine the mean glandular dose to a nominal 4.5
centimeter compressed breast for systems not equipped with either
an mAs or elapsed exposure time indicator:
1) Procedure No. 1 - No Mammography Dosimetry Test Phantom
A) Temporarily install either an mAs meter or elapsed
exposure on-time indicator on the x-ray system. This
installation shall be done by a person competent in
electrical circuitry to avoid electrical hazards.
B) Follow the procedures listed under subsection (b)(2)
above.
2) Procedure No. 2 - With a Dosimetry Test Phantom
Follow the procedures in subsection (b)(1) above.
(Source: Added at 15 Ill. Reg. 6180, effective April 16, 1991)
Section 360.ILLUSTRATION A Thimble and Pancake Chamber - Radiation Measuring
Device
(Source: Added at 15 Ill. Reg. 6180, effective April 16, 1991) Section 360.ILLUSTRATION B Mammography Dose Evaluation Graph
Working curves for evaluating the average glandular dose delivered by 1 R in
air incident on a 4.5 centimeter compressed breast thickness (vertical axis)
vs. first HVL in mmAl (horizontal axis). The solid line represents tungsten
tube target data. The broken line represents molybdenum or molybdenum/
tungsten target tube data. (Excerpt from NCRP 85)
(Source: Added at 15 Ill. Reg. 6180, effective April 16, 1991)
Section 360.TABLE A Filtration Required as a Function of Operating kVp
(Repealed)
(Source: Repealed at 13 Ill. Reg. 803, effective April 1, 1989)
Section 360.TABLE B Half-Value Layer as a Function of Tube Potential
X-ray Tube Voltage
(kilovolt peak) Minimum HVL (mm of Al) (1)
Indicated Specified Other
Designed operating Operating Dental X-Ray
range Potential (2) Systems (3) Systems (4)
(1) AGENCY NOTE: Linear extrapolation or interpolation may be made for an
x-ray tube potential (kVp) not listed in Table B above (e.g., in the
column entitled "Other X-ray Systems" operated at 20 kVp and 95 kVp, the
minimum HVL required would be 0.2 and 2.6 mm of Al respectively).
(2) AGENCY NOTE: If the HVL determination for an x-ray system is below the
minimum value specified for a given voltage, as indicated at the control
panel, the actual kilovoltage should be measured and the HVL
reevaluated.
(3) AGENCY NOTE: "Specified Dental Systems" means any dental x-ray system
designed for use with intraoral image receptors and manufactured after
December 1, 1980.
(4) AGENCY NOTE: "Other X-ray Systems" means all x-ray systems required to
meet the provisions of Sections 360.50, 360.60, 360.70, 360.80, 360.90
(except "Specified Dental Systems") and 360.100.
(Source: Amended at 13 Ill. Reg. 803, effective April 1, 1989)
Section 360.TABLE C Entrance Exposure Limits Per Intraoral Bitewing Film
Operating Maximum Exposure (1) Minimum Exposure (2)
(kVp) (milliroentgens) (milliroentgens)
45 640 430
50 600 400
55 560 370
60 520 320
65 480 270
70 440 220
75 400 175
80 360 140
85 320 115
90 280 100
95 240 95
100 200 90
(1) AGENCY NOTE: Linear extrapolation or interpolation may be made for an
x-ray tube potential (kVp) not listed in Table B above (e.g., bitewing
radiographs taken at 44 kVp and 72 kVp, the maximum entrance exposure
permitted would be 648 milliroentgens and 424 milliroentgens
respectively).
(2) AGENCY NOTE: The minimum exposures specified in the above table are
included as recommendations only. They were empirically determined by a
panel of dentists in a U.S. FDA, BRH study. They represent the minimum
exposure which was found to be necessary to produce a diagnostic quality
radiograph when a dental phantom, speed group "D" film, and adequate
film development procedures were used. However, some x-ray units
manufactured after 1980, or x-ray units used in conjunction with dental
film of the ultra speed group "E", may be capable of generating
exposures lower than listed in this table.
(Source: Amended at 15 Ill. Reg. 6180, effective April 16, 1991)
