Air density correction

The air density correction describes an adjustment of the location-specific air density in the calculation model of a measurement process. The air density correction can be determined with a control device.

Applications

When measuring a radiation dose using a dosimeter, there are two variants that are equipped with either an open or a closed ionization chamber . If the measurement is carried out with a closed ionization chamber that is filled with a constant gas, no correction of the density is required . An open chamber, on the other hand, which is operated with ambient air, requires an air density correction factor. Air-density-corrected data, based on the reference temperature 293.15 Kelvin and the reference air pressure 1013.25 hPa, are given in the calibration certificate of the measuring device.

Web links

• Dose measurement method radiotherapy air density correction (PDF; 14.2 MB) page 17. Accessed May 8, 2013
• Calibration of location-independent reference dosimeter systems (PDF; 19 kB) page 2, section 5.7, air density correction during testing