(a) The leakage radiation from the tube
housing shall not exceed a radiation level of 2.5 milliroentgens in 1 hour at 5
centimeters from the surface of the tube housing at any specified tube
(b) Radiation originating
within the high voltage power supply (i.e., transformer and rectifiers) shall
not exceed a radiation level of 0.5 milliroentgen in 1 hour at every specified
rating at a distance of 5 centimeters from the housing of the power
(c) A warning light with
the notation "X-Ray On," or equivalent shall be located on the control panel
and shall light only when the x-ray tube is activated. This light shall be a
fail-safe design or administrative controls shall be exercised to ensure
operations will not continue without a proper functioning warning light. On
equipment installed after October 2, 1978, this device shall be a fail-safe
The x-ray accessory
apparatus shall include a beam trap or other barrier with sufficient shielding
so that the dose rate due to the transmitted primary beam does not exceed 0.25
mrem/hr at 5 centimeters under normal operating conditions. The dose rate may
be difficult to evaluate in the presence of scattered radiation, however, this
requirement shall be considered met if the inherent shielding of the trap or
barrier is at least equivalent to the thickness of lead specified in Table RHS
3-5 for the maximum rated anode current and potential.
Table RHS 3-5 THICKNESS OF LEAD REQUIRED FOR A PRIMARY BEAM
BARRIER LOCATED 5 CENTIMETERS FROM THE FOCAL SPOT
Thickness of lead (mm)
light or indicator in a conspicuous location near the tube housing assembly
shall be used to indicate when the x-ray tube is on. This light or other
indicator shall be of failsafe design or administrative controls shall be
exercised to ensure operations will not continue without proper functioning of
this light or indicator. On equipment installed after October 2, 1978, this
device shall be of fail-safe design.
In addition to any signs or labels
required in Rule
a sign or label shall be placed on or adjacent to each x-ray tube housing and
shall be located so as to be clearly visible to any individual who may be
working in close proximity to the primary beam path. The sign or label shall
bear the words:
"CAUTION - HIGH INTENSITY X-RAY BEAM"
(g) Where couplings exist, e.g., between the
x-ray tube and the collimator of the diffractometer, etc., they shall prevent
radiation from escaping the coupling.
(h) Each port of the radiation source housing
shall be provided with a beam shutter interlocked with the x-ray accessory
apparatus coupling, or collimator, in such a way that the port will be open
only when the collimator or coupling is in place. Shutters at unused ports
shall be secured to prevent inadvertent opening.
Open beam x-ray equipment
1. All shutters shall be provided with a
"shutter open" indication of fail-safe design.
2. Radiation levels in the vicinity of
controls and adjustments of the x-ray accessory apparatus used during normal
operation shall be such that the operator's exposure shall not exceed in one
hour 37 mrem to the hands or 2 mrem to the whole body, gonads, bloodforming
organs, or lens of the eye.
guard or interlock which prevents entry of any part of the body into the
primary beam path should be utilized.
4. The operator shall be in immediate
attendance at all times when the equipment is in operation except when the area
is locked to protect against unauthorized or accidental entry.
5. When not in use, equipment shall be
secured in such a manner as to be inoperable by unauthorized persons.
Enclosed beam x-ray equipment
1. The radiation source, sample, detector and
analyzing crystal (if used) shall be enclosed in a chamber or coupled chambers
that cannot be entered by any part of the body during normal
2. The sample chamber
closure shall be interlocked with the x-ray tube high voltage supply or a
shutter in the primary beam so that no x-ray beam can enter the sample chamber
while it is open unless the interlock has been conspicuously and deliberately
defeated. The interlock required by this section shall be of failsafe design or
adequate administrative controls shall be exercised to ensure operations will
to continue without a proper functioning interlock.
3. The exposure
level at 5 centimeters from the tube housing apparatus complex shall not exceed
2.5 milliroentgens per hour during normal operation.
Operation of equipment.
The registrant shall not permit any
individual to operate or maintain analytical x-ray equipment until such
individual has received instruction in and demonstrated competence as to:
1. Identification of radiation hazards
associated with the use of the equipment;
2. Significance of the various radiation
warning and safety devices incorporated into the equipment, or the reasons they
have not been installed on certain pieces of equipment and the extra
precautions required in such cases;
3. Proper operating procedures for the
4. Symptoms of an acute
localized exposure; and
procedures for reporting an actual or suspected exposure.
(b) Procedures and apparatus utilized in beam
alignment shall be designed to minimize radiation exposure to the
(c) Written operating
procedures and emergency procedures pertaining to radiation safety shall be
established for each facility and shall be conspicuously posted in a location
near each unit of analytical x-ray equipment.
(d) Only trained personnel shall be permitted
to install, repair, or make modifications to the x-ray generating apparatus and
the tube housing apparatus complex.
Any temporary alteration to safety
devices, such as by-passing interlocks or removing shielding shall be:
1. Approved in advance by the radiation
2. Specified in
writing and posted near the x-ray tube housing so that other individuals will
know the existing status of the x-ray apparatus.
3. Terminated as soon as possible.
4. Recorded and the record maintained for
inspection by the Division. This record should contain such information as date
alteration was made, type of alteration, length of time unit remained in the
altered condition, and signed by the individual who made the alteration and the
individual who restored the unit to original condition.
(f) Tests of all safety devices such as
interlocks, shutters, and warning lights shall be conducted at intervals not to
exceed 3 months for all operable analytical x-ray equipment. Records of such
tests shall be maintained for inspection by the Division.
(g) Interlocks shall not be used to
de-activate the x-ray tube, except in an emergency or during testing of the
interlock system. After such shut-off, it shall be possible to restore the
machine to full operation only from the control panel.
In addition to the
requirements of paragraphs (1) and (2) of this rule, the following requirements
apply to open-beam, hand-held, analytical X-ray devices:
All registrants possessing open-beam, hand-held, analytical
devices shall have available for review by the Division operating policies and
procedures that contain measures to ensure that:
Radiation protection is provided equivalent to that afforded in subparagraph
(1)(d) of this rule. This shall be in the form of an operating procedure that
contains, at a minimum:
(i) The operator's
hands will not approach the primary beam;
(ii) The operator will not hold the sample
during operation of the hand-held x-ray device;
(iii) The operator will not aim the primary
beam at him/herself or at any individual during operation of the device;
(iv) Before energizing the
device, the operator will ensure that no person is within two meters of the
device or sample being tested.
If the safety devices, which are known as
the "X-ray On" warning light and the tube housing "X-ray On" indicator light,
as outlined in subparagraphs (1)(c) and (1)(e) of this rule, are not of a
fail-safe design, administrative controls shall be put in place in the form of
an operating procedure that shall include, at a minimum:
(i) Discussion of the warning light(s) safety
mechanism on the device, the rationale behind subparagraphs (1)(c) and (1)(e)
of this rule, the absence of the fail-safe design on the device, and the
potential risks to the operator should the warning light(s) fail;
(ii) Training the operator to visually verify
that the warning light(s) is correctly working when the device is known to be
the operator to recognize warning light failure. For example: warning light(s)
not functioning when the device is known to be generating X-rays, or if one of
several warning lights is not operating;
(iv) Proper procedures for reporting an
actual or suspected warning light failure; and
(v) If failure of the warning light, or any
one of the warning lights if there are multiple warning lights, is confirmed,
the analyzer will immediately be removed from service and returned to the
manufacturer for repair. Return to service will not be permitted until
necessary repair has been performed, and the maintenance record for the device
updated. Such maintenance records shall be made available upon request by the
radiation exposure is as low as reasonably achievable. For example, use of
ancillary equipment when possible, such as a sample holder.
The registrant shall provide and require individual personnel
monitoring with extremity dosimeters for all operators of the hand-held device
in compliance with Chapter 0400-20-05. Extremity monitoring may be discontinued
after one year if the results of the personnel monitoring demonstrate that the
operator of the hand-held device is not likely to receive a dose in excess of
10 percent of the limits in Rule
as outlined in Rule
The registrant shall maintain records of doses received by all individuals for
whom monitoring was required pursuant to Rules
In addition to the training requirements of subparagraph
(2)(a) of this rule, the registrant shall provide training for all users and
operators on the requirements of subparagraph (a) and (b) of paragraph. Records
of all user and operator training shall be maintained and made available for
review by the Division. Training records shall include:
1. The date the training was
2. The name of each
individual trained (printed) and their signature;
3. The name and dated signature of the
individual providing the training;
4. The topics covered in the training (or an
attachment of the training material); and
The duration of the training.
9 This part is intended to apply
to units that are hand-held. Analytical units designed to be hand-held but
operated in a fixed configuration and not hand-held shall be subject to the
requirements of subparagraph (1)(d) of this rule.