Code of Maine Rules › 10 - DEPARTMENT OF HEALTH AND HUMAN SERVICES › 144 - DEPARTMENT OF HEALTH AND HUMAN SERVICES - GENERAL › Chapter 220 - Rules Relating to Radiation Protection › Part F - X-RAYS IN THE HEALING ARTS › Section 144-220-F-5 - General requirements for all diagnostic x-ray systems

Current through 2024-29, July 17, 2024
In addition to other requirements of this part, all
					 diagnostic x-ray systems shall meet the following requirements:
A. Warning label. The control panel
				  containing the main power switch shall bear the warning statement, legible and
				  accessible to view: "WARNING: This x-ray unit may be dangerous to patient and
				  operator unless safe exposure factors and operating instructions are
				  observed."
B. Battery charge
				  indicator. On battery-powered x-ray generators, visual means shall be provided
				  on the control panel to indicate whether the battery is in a state of charge
				  adequate for proper operation.
C.
				  Leakage radiation from the diagnostic source assembly. The leakage radiation
				  from the diagnostic source assembly measured at a distance of 1 meter in any
				  direction from the source shall not exceed 100 milliroentgens (25.8 mC/kg) in
				  one hour when the x-ray tube is operated at its leakage technique factors.
				  Compliance shall be determined by measurements averaged over an area of 100
				  square centimeters with no linear dimension greater than 20
				  centimeters.
D. Radiation from
				  components other than the diagnostic source assembly. The radiation emitted by
				  a component other than the diagnostic source assembly shall not exceed 2
				  milliroentgens (0.516 mC/kg) in one hour at 5 centimeters from any accessible
				  surface of the component when it operated in an assembled x-ray system under
				  any conditions for which it was designed. Compliance shall be determined by
				  measurements averaged over an area of 100 square centimeters with no linear
				  dimension greater than 20 centimeters.
E. Beam Quality.
(1) Half-value layer.
(a) 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 1. If it is necessary to determine such half-value layer at an x-ray tube
				  potential, which is not listed in Table 1, linear interpolation or
				  extrapolation may be made.
TABLE 1
Minimum HVL (mm of
									 AL)
Design operating range (Kilovolts peak)
Measured potential (kVp)
Specified dental systems*
All other diagnostic X-ray systems
Below 50 ---------
30
1.5
0.3
40
1.5
0.4
49
1.5
0.5
50 to 70 ---------
50
1.5
1.2
60
1.5
1.3
70
1.5
1.5
Above 70 ---------
71
2.1
2.1
80
2.3
2.3
90
2.5
2.5
100
2.7
2.7
110
3.0
3.0
120
3.2
3.2
130
3.5
3.5
140
3.8
3.8
150
4.1
4.1
* for any dental x-ray system designed for use
								  with intraoral image receptors and manufactured after December 1, 1980;
(b)
				  The requirements of F.5.E.1(a) will be considered to have been met if it can be
				  demonstrated that the aluminum equivalent of the total filtration in the
				  primary beam is not less than that shown in Table 2.
TABLE 2
Filtration Required
								  vs. Operating Voltage
Total Filtration (inherent plus added)
Operating Voltage (kVp)
(millimeters aluminum equivalent)
Below 50 -----------------------------------
0.5
50 - 70
								  --------------------------------------
1.5
Above 70
								  -----------------------------------
2.5
(c)
				  The required minimal half value layer of the useful beam shall include the
				  filtration contributed by all materials, which are permanently between the
				  source and the patient.