New Hampshire Code of Administrative Rules
He - Department of Health and Human Services
Subtitle He-P - Former Division of Public Health Services
Chapter He-P 4000 - NEW HAMPSHIRE RULES FOR THE CONTROL OF RADIATION
Part He-P 4046 - USE OF RADIATION MACHINES: GENERAL REQUIREMENTS FOR ALL DIAGNOSTIC AND VETERINARY X-RAY SYSTEMS
Section He-P 4046.01 - General Requirements for All Diagnostic X-ray
Current through Register No. 40, October 3, 2024
In addition to the requirements of He-P 4040 through He-P 4045, all diagnostic x-ray systems shall meet the following requirements:
(a) The control panel containing the main power switch shall bear a warning label that shall be legible, accessible to view, and shall state:
"WARNING: THIS X-RAY UNIT MAY BE DANGEROUS TO PATIENT AND OPERATOR UNLESS SAFE EXPOSURE FACTORS AND OPERATING INSTRUCTIONS ARE OBSERVED";
(b) For battery-powered x-ray systems, 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) Means shall be provided to permit further limitation of the field;
(d) The radiation emitted by a component other than the diagnostic source assembly shall not exceed 2 milliroentgens in one hour at 5 centimeters from any accessible surface of the component when it is operated in an assembled x-ray system under any conditions for which it was designed;
(e) Compliance with the requirements of He-P 4046.01(f) shall be determined by measurements averaged over an area of 100 square centimeters with no linear dimension greater than 20 centimeters;
(f) 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 4046.1;
Table 4046.1 Tube Potential v. Minimum Half-Value Layer
| Design Operating Range | Measured Potential | Dental Intraoral Manufactured After 12/1/1980 | Dental Intraoral Manufactured on or Before 12/1/1980 (and all other x-ray systems manufactured before 6/10/2006) | All X-ray Systems except Dental Intraoral Manufactured on or after 6/10/2006. |
| (kVp) | (kVp) | (Half-Value Layer In mm Aluminum) | (Half-Value layer mm Aluminum) | (Half-Value Layer In mm Aluminum) |
| Below 51 | 30 | N/A | 0.3 | 0.3 |
| 40 | N/A | 0.4 | 0.4 | |
| 50 | 1.5 | 0.5 | 0.5 | |
| 51 to 70 | 51 | 1.5 | 1.2 | 1.3 |
| 60 | 1.5 | 1.3 | 1.5 | |
| 70 | 1.5 | 1.5 | 1.8 | |
| Above 70 | 71 | 2.1 | 2.1 | 2.5 |
| 80 | 2.3 | 2.3 | 2.9 | |
| 90 | 2.5 | 2.5 | 3.2 | |
| 100 | 2.7 | 2.7 | 3.6 | |
| 110 | 3.0 | 3.0 | 3.9 | |
| 120 | 3.2 | 3.2 | 4.3 | |
| 130 | 3.5 | 3.5 | 4.7 | |
| 140 | 3.8 | 3.8 | 5.0 | |
| 150 | 4.1 | 4.1 | 5.4 |
(g) For capacitor energy storage equipment, compliance with the requirements of He-P 4046.01(g) and He-P 4046.01(f) shall be determined with the system fully charged and a setting of 10 mAs for each exposure;
(h) The required minimum half-value layer of the useful beam shall include the filtration contributed by all materials which are permanently between the source and the patient;
(i) For x-ray systems which have variable kVp and variable filtration for the useful beam, a device shall link the kVp selector with the filter(s);
(j) Where 2 or more radiographic tubes are controlled by one exposure switch, the tube or tubes which have been selected shall be clearly indicated on the x-ray control panel and on or near the selected tube housing assembly prior to the exposure initiation;
(k) 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;
(l) Technique factors to be used during an exposure shall be indicated before the exposure begins;
(m) If automatic exposure controls are used, the technique factors which are set prior to the exposure shall be indicated;
(n) Indication of technique factors shall be visible from the operator's position except in the case of spot-films made by the fluoroscopist;
(o) Diagnostic x-ray systems and their associated components used on humans and certified pursuant to the "Performance Standards for Ionizing Radiation Emitting Products" (21 CFR Part 1020) shall be maintained in compliance with applicable requirements of that standard; and
(p) All position locking, holding, and centering devices on x-ray system components and systems shall function as intended.
#6827, eff 8-6-98; ss by #8692, INTERIM, eff 7-27-06, EXPIRES: 2-2-07; ss by #8808, eff 1-24-07
