NBN EN 12544-2:2000

This standard specifies a constancy check of a X-ray system where mainly the X-ray voltage is checked and also the tube current and the constitution of the target which can be changing due to ageing of the tube. The thick filter method is based on a measurement of the dose rate behind a defined thick filter using defined distances between the X-ray tube, the filter and the measuring device. This method is very sensitive to changes of the voltage, but it does not provide an absolute value for the X-ray tube voltage.