ontent.
DETAILED TABLE OF CONTENTS

7-i

DEPARTMENT OF COMMUNITY HEALTH

RADIATION SAFETY SECTION

IONIZING RADIATION RULES


DETAILED TABLE OF CONTENTS


PART 7. MEDICAL X-RAY INSTALLATIONS.
Page

R325.5<b>311. Purpose and scope............................................................................................... 7-1


THERAPEUTIC MACHINES OPERATED ABOVE 85 KVP

R325.5<b>312. X-ray equipment ................................................................................................. 7-1
R325.5<b>315. Enclosures........................................................................................................... 7-2
R325.5<b>317. Conditions of operation ...................................................................................... 7-2


THERAPEUTIC MACHINES OPERATED AT OR BELOW 85 KVP

R325.5<b>321. X-ray equipment ................................................................................................. 7-3
R325.5<b>322. Enclosures........................................................................................................... 7-3
R325.5<b>323. Conditions of operation ...................................................................................... 7-3


FIXED RADIOGRAPHIC INSTALLATIONS

R325.5<b>325. X-ray equipment ................................................................................................. 7-3
R325.5<b>331. Enclosures........................................................................................................... 7-5
R325.5<b>333. Conditions of operation ...................................................................................... 7-5


FIXED FLUOROSCOPIC INSTALLATIONS

R325.5<b>337. X-ray equipment ................................................................................................. 7-6
R325.5<b>347. Enclosures........................................................................................................... 7-8
R325.5<b>348. Conditions of operation ...................................................................................... 7-8


MOBILE OR PORTABLE DIAGNOSTIC X-RAY EQUIPMENT

R325.5<b>351. X-ray equipment ................................................................................................. 7-8
R325.5<b>352. Shielding............................................................................................................. 7-9
R325.5<b>353. Conditions of operation ...................................................................................... 7-9


MISCELLANEOUS AND SPECIAL INSTALLATIONS

R325.5<b>355. General provisions.............................................................................................. 7-9



7-ii

Page
APPENDICES

R325.5<b>357. Appendix A. Table 1.......................................................................................... A-1
R325.5<b>358. Appendix A. Table 2.......................................................................................... A-1
R325.5<b>359. Appendix B. National Electrical Code ...............................................................B-1
Article 100 - Definitions.....................................................................................B-1
Article 500 - Hazardous (Classified) Locations .................................................B-1
Article 517 - Health Care Facilities....................................................................B-1
Article 660 - X-Ray Equipment..........................................................................B-3

7-1

PART 7. MEDICAL X-RAY INSTALLATIONS


R325.5311. Purpose and scope.

Rule 311. (1) This part establishes requirements
governing the use of x-radiation in medicine, osteopathy,
chiropractic and podiatry.

(2) This part applies to all licensees and registrants who
use x-radiation in these healing arts disciplines for the
intentional exposure of humans.

(3) In addition to this part all licensees and registrants are
subject to parts 1, 4 and 5 and all applicable provisions of the
other parts.


THERAPEUTIC MACHINES OPERATED
ABOVE 85 KVP

R325.5312.
X-ray equipment.

Rule 312. (1)
The tube housing shall be of the
therapeutic type.

(2) Permanent diaphragms or cones used for collimating
the useful beam shall afford the same degree of attenuation as is
required of the housing.

(3) Adjustable or removable beam-limiting devices shall
transmit not more than 5% of the useful beam as determined at
the maximum tube potential and with maximum treatment filter.

(4) Filters shall be so mounted as to prevent their
movement during the treatment.

(5) The filter slot shall be so constructed that the radiation
escaping through it does not produce an exposure rate exceeding
1 R/h at 1 meter, or if the patient is likely to be exposed to
radiation escaping from the slot, 30 R/h at 5 centimeters (2
inches) from the external opening.

(6) A removable filter shall be permanently marked with
its thickness and material.

(7) A filter indication system shall be used on therapy
machines which use changeable filters and are manufactured
after the effective date of these rules. It shall indicate, from the
control panel, the presence or absence of any filter and it shall
be designed to permit easy recognition of the filter in place.

(8) The x-ray tube shall be so mounted that it cannot turn
or slide with respect to the housing aperture. A reproducible
means of measuring the focal spot to patient distance shall be
provided.

(9) Means to immobilize the tube housing during
stationary portal treatment shall be provided.

(10) An easily discernible indicator which shows whether or
not x-rays are being produced shall be on the control panel.

(11) On therapeutic machines manufactured after the
effective date of these rules beam monitoring devices shall be
fixed in the useful beam to indicate any error due to incorrect
filter, tube current, or tube potential, unless the device
introduces more filtration than is clinically acceptable.

(12) A suitable exposure control 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. If a timer is used, it shall permit
accurate presetting and determination of exposure times as short
as 1 second. Means for the operator to terminate the exposure at
any time shall be provided.

(13) Mechanical or electrical stops or both shall be provided
to insure that the useful beam is oriented only toward primary
barriers.

(14) Interlocks shall be provided so that, when any door to
the treatment room is opened, the machine will shut off
automatically or the radiation level within the room will be
reduced to an average of not more than 2 mR/h and a maximum
of 10 mR/h at a distance of 1 meter in any direction from the
source. After the shut-off or reduction in exposure rate, it shall
be possible to restore the machine to full operation only from
the control panel.

(15) The x-ray control circuit shall be so designed that it is
not possible to energize the x-ray tube to produce x-rays without
resetting the x-ray "ON-OFF" switch at the control panel.

(16) When the relationship between the beam interceptor
(when present) and the useful beam is not permanently fixed,
mechanical or electrical stops shall be provided to insure that
the beam is oriented only toward primary barriers.

(17) X-ray equipment installed after the effective date of
these rules shall be installed and used in accord with the
appropriate portions of the 1975 national electrical code (NFPA
No. 70-1975) reproduced or referenced in rule 359. X-ray
equipment installed before the effective date of these rules shall
conform with the appropriate national electrical code in effect at
the time of installation.

(18) X-ray machines with electron beam extraction
capability shall be provided with such additional safety devices
as determined necessary and specified in writing by the
department to prevent accidental electron beam exposure.

(19) To reduce the electron contamination of high energy
treatment beams, shadow trays or other accessories placed in the
primary beam shall be placed at a sufficient distance from the
patient that the electron contamination contribution to the skin
dose is minimal.


7-2
(20) X-ray machines capable of producing radioactive
material in excess of exempt quantities listed in schedule B of
rule 147 unless excluded from the particle accelerator definition
in part 1 by design and use shall comply with the applicable
requirements of part 11.

R325.5315.
Enclosures.

Rule 315. (1) An enclosure shall be a permanent part of
the building or equipment. Portable protective barriers shall not
be used for permanent installations.

(2) The degree of protection required for an enclosure shall
be determined by the workload, use and occupancy factors and
the kilovoltage, milliamperage, mechanical movement, and
distance factor, and shall be subject to design approval by the
department.

(3) All wall, ceiling