A survey of fluoroscopic equipment in Victoria

A survey of fluoroscopic units in the state of Victoria has been carried out. For fixed fluoroscopy equipment, routine quality assurance tests were carried out on the x-ray tube used for conventional radiographs, and factors relating to image quality and patient dose were measured for the screening tube. For the mobile image intensifiers, quality assurance tests were carried out and factors relating to image quality and patient dose were measured. There was a ratio of about 20 in the dose rates between the units with the highest and lowest screening dose rates with the same size phantom. Guidance levels based on the third quartile values of the entrance dose rates and spot film doses are recommended. The recommended guidance doses are: mobile image intensifier: dose rate: 30 mGy/min; fixed screening unit: dose rate: 42 mGy/min and spot film: 5 mGy.