Development of a measuring system for determining the air density correction factor for ionization chambers open to the atmosphere

Abstract

This paper introduces a measuring system designed to determine the air density correction factor for ionization chambers open to the atmosphere. The system is intended for use in clinical and radiotherapy facilities, secondary standard dosimetry laboratories, and other settings where open-to-the-air ionization chambers are commonly utilized. While there are numerous universal and laboratory-grade instruments available for measuring relative humidity, air pressure, and ambient temperature, integrated systems that can measure these parameters and calculate and display the air density correction factor are rare, particularly in the domestic market in Serbia. This paper details the developed hardware, including specifications for the sensors used, as well as the software developed for microcontrollers and personal computers. Measurement results and simplified measurement uncertainty budgets are also presented and discussed.

Keywords

• ionization chamber
• dosimetry
• air density
• air temperature
• atmospheric pressure
• correction factor
• calibration
• sensor