Personal dosimeters are used by medical radiation workers (MRWs) to monitor their radiation dose from external sources and comply with radiation safety guidelines. Nevertheless, there is evidence of inconsistent use of the devices among MRWs. Behavioral factors influencing the use of personal dosimeters have never been explored. Using established behavioral models, we aimed to develop a psychometric tool to measure the behavioral factors influencing dosimeter use and establish its feasibility, reliability, and validity. A 37-item tool was developed based on a qualitative study and review of the literature. The content relevancy was assessed by six field experts before it was piloted and re-tested on MRWs. The construct validity of the tool was analyzed using exploratory factor analysis to confirm its psychometric properties. Face validation was performed by academicians, field experts, and MRWs to enhance the tool's readability. The 37 items in the tool belonged to five constructs in the early phase. However, the validation study revealed a reliable 27 item tool with seven constructs, namely: "Attitude," "Social factors," "Ability to perform if facilitated," "Ability to overcome shortcomings," "Self-efficacy," "Complexity," and "Perceived usefulness." The item-construct validity index of accepted items was >0.83, and Cronbach's alpha for each construct ranged between 0.70 to 0.96, while factor loading for each item was between 0.723 to 0.963. All results were considered "good" and "excellent." The new tool appears to be valid, reliable, and feasible to measure behavioral factors influencing personal dosimeter use among MRWs, which is helpful to facilitate the planning of interventions to improve behaviors in occupational radiation monitoring.