10-144-220 Me. Code R. § F-5

Current through 2024-51, December 18, 2024
Section 144-220-F-5 - General requirements for all diagnostic x-ray systems

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.
(2) Filtration controls. For x-ray systems constructed after 1974, which have variable kVp and variable filtration for the useful beam, a device shall link the kVp selector with the filter(s) and shall prevent an exposure unless the minimum amount of filtration necessary to produce the HVL required by F.5.E.(1) is in the useful beam for the given kVp, which has been selected.
F. Multiple tubes. Where two or more radiographic tubes are controlled by one exposure switch, the tube or tubes, which have been selected, shall be clearly indicated prior to initiation of the exposure. This indication shall be on the x-ray control panel.
G. 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.
H. Technique indicators.
(1) The technique factors to be used during an exposure shall be indicated before the exposure begins. If automatic exposure controls are used the technique factors which are set prior to the exposure shall be indicated.
(2) The requirement of F.5.H(1) may be met by permanent markings on equipment having fixed technique factors. Indication of technique factors shall be visible from the operator's position except in the case of spot films made by the fluoroscopist.
I. Quality assurance program
(1) Each hospital, out-patient clinic, chiropractic, and private medical facility, to include approved screening programs that are performing diagnostic x-rays on humans shall establish an active quality assurance program. The quality assurance program shall incorporate the standards and records indicated in Appendix G, Quality Assurance Requirements for Facilities Performing Diagnostic X-Ray.
(2) The QA program for mammographic facilities shall be inspected by the Department annually. All other, non-dental, radiographic facilities, shall have their QA program inspected by the department prior to the end of the periodic survey time frame.
(3) All position locking, holding, and centering devices on x-ray system components and systems shall function as intended.

10-144 C.M.R. ch. 220, § F-5