A simple penetrameter

A penetrameter, which is a device for checking the kVp calibration of an X-ray generator, has been designed and constructed in the University of Ilorin using locally available materials. The device consists of a 2 mm thick sheet of aluminium used as a beam hardener, stacks of various numbers of aluminium discs for beam attenuation, Perspex for support and an X-ray film cassette for detection. The identification of dots of equal optical density is made using a densitometer also made by one of the authors. The device has been tested in the Radiology department of the University of Ilorin Teaching Hospital on a diagnostic range X-ray machine and found to be satisfactory. It is simpler and less expensive than imported penetrameter cassettes.