Looking at the circuit board, the eight red lamps on the lower left are LED1-LED8 from bottom to top. Therefore, if any part of the useful beam extends beyond the edges of the PPB, the fluoroscopist could be exposed directly to the beam. Second, some image in-tensifiers emit radiation during operation due to the type of electron-ic components employed. The A2060X firmware makes sure that the x-ray head cannot be turned on for more than a certain fraction of the time. In firmware version 4, this fraction is 1/32, so that we can have, for example, a 1-s exposure every thirty seconds. When so provided, the equipment shall not be operable at any combination of tube potential and current which will result in an exposure rate in excess of 5 R/min at the point where the center of the useful beam enters the patient, unless the high level control is activated.
The federal performance standard allows for a finite amount of misalignment between the light field and x-ray field. When programmed with firmware P2060X04, the A2060X controls a Siemens Heliodent x-ray source, part number 5938733D3195, designed for dental use. The photograph below shows one of these systems fully-assembled. One function of the x-ray head is to stop the x-ray from over-heating.
Thus the provisions of the standard for certain systems allow further reduction of the x-ray field at the dis-cretion of the radiographer.Since each x-ray system is unique in its performance, the x-ray field/image receptor alignment problems are also unique. This decrease in high voltage results in lower energy x-rays being produced such that more of them are absorbed in the target, glass envelope, filters and other components of the tube housing. The value of 2 mR/hr for each R/min of EER has been established as an occupationally acceptable level and the requirement can be met quite easily through appropriate design and assembly.Two additional qualifications for measuring compliance are contained in the provisions of the standard.