RADIATION EXPOSURE DURING EQUINE RADIOGRAPHY

Abstract

All personnel present in the X‐ray examination room during equine radiography were monitored using low energy direct reading ionization chambers (pockets dosimeters) worn outside the lead apron at neck level. The individuals' task and dosimeter readings were recorded after each examination. Average doses ranged from 0 to 6 mrad per study. The greatest exposures were associated with radiography of the shoulder and averaged less than 4 mrad. The individual extending the horse's limb was at greatest risk although the individual holding the horse's halter and the one making the X‐ray exposure received similar exposures.A survey of the overhead tube assembly used for some of the X‐ray examinations also was performed. Meter readings obtained indicated an asymetric dose distribution around the tube assembly, with the highest dose occurring on the side to which the exposure cord was attached.Although the exposures observed were within acceptable limits for occupational workers, we have altered our protocol and no longer radiograph the equine shoulder unless the horse is anesthetized. Continued use of the pocket dosimeters and maintenance of a case record of radiation exposure appears to make the technologists more aware of radiation hazards.