Radiation Exposure Survey of Personnel at the Cleveland Clinic Foundation

Within recent years there has been a considerable increase in the use of x-rays and radioactive substances in the diagnosis and treatment of disease. As a result, the problem of adequate protection has become greatly magnified. In an effort to ascertain that all radiologic procedures at the Cleveland Clinic were safely instituted, and to familiarize the personnel with radiation hazards, a comprehensive survey involving 84 persons was conducted over a period of three months. The principle of blackening of film was employed as a means of measuring ionizing radiations. Film badges furnished by Tracerlab, Inc. (Boston) were used, containing two films of different sensitivity and equipped, also, with small filters of lead, copper, and cadmium. The badges were worn for one week and then developed by Tracerlab, Inc., under standard conditions. The results were reported in milliroentgens (mr) per week. The maximum permissible dose for exposure of the whole body to x, gamma, and beta radiation is 0.3 r per week, as recommended by the International Commission of Radiological Protection. In the investigations to be described, whenever this level was exceeded as measured by the film badges, a further investigation was instituted to determine the cause. For simplification we have broken the results of the survey into various specific groups. Diagnosis Clinic Department of Diagnostic Roentgenology: The section of diagnostic roentgenology occupies approximately 15,000 feet of the second floor of a ten-story building. Figure 1 shows the floor plan of this section. Frequent reference will be made to this plan in showing the relationship of the various personnel to the radiation sources. Four desk and dressing room girls act as receptionists in the main waiting room and in the dressing rooms and are stationed at points 1 and 2 as indicated on the floor plan. The activity of these girls is limited to that portion of the department which is not shaded on the plan. This includes the main waiting room, both dressing rooms, adjacent lavatories, and a women's powder room. Film badges worn by these girls never showed darkening. There are twelve x-ray technicians, six operating in the men's wing and six in the women's wing. The average number of exposures handled by one technician is 200 per week. The maximum limit of all diagnostic equipment is 90 kv. and 500 ma. Seven diagnostic units are installed in each wing, as noted on the floor plan. Adequate amounts of concrete provide protection in the floors and ceiling of these fourteen rooms. The wall of the rooms is lined with a minimum of 2 mm. of lead. The control panels are well shielded behind lead walls, except in the fluoroscopic rooms, and there is no occasion for exposure of any of the technicians.