With increasing use of CT in children and a lack of use of appropriateness criteria, there is a strong need to implement guidelines to avoid unnecessary radiation doses to children.

No abstract

Measurements of absorbed dose rates in air and tissue produced by low-energy x radiation are often difficult to obtain with accuracy. The recommended instruments for these applications are extrapolation chambers. The performance of an extrapolation chamber, developed at IPEN, was studied in low energy x radiation standard beams in relation to its response linearity, extrapolation curves and energy dependence. The results obtained indicate that the developed chamber is suitable for x radiation measurements.