Dose Area Product (DAP) Meters



The Source to Imager Distance (SID) is 100cm. The Source to Skin Distance (SSD) is 49 cm (100cm minus both the patient's thickness and air gap).

The Receptor Field Radius (RFR) is 30.5cm/2 or 15.25cm. The Skin Field Radius (SFR) is unknown, and is needed to calculate the exposed area at the patient's skin.

The ratio of SFR/SSD = RFR/SID