## 1 Introduction  
Medical imaging is critical in healthcare since it provides significant benefits for the diagnosis and treatment of patients. As a result, spurred by its many applications and advances in medical technology, the worldwide usage of ionizing radiation in healthcare has grown rapidly [1]. Technetium-99m (Tc-99m) is a medical radioisotope created from Molybdenum-99 (Mo-99), and it is the most commonly utilized medical radioisotope in nuclear medicine [2]. Tc-99m offers various advantages, including a half-life of around six hours, which limits patient exposure, and it is swiftly eliminated from the patient's body, reducing any potential harm [3]. There is also a monoenergetic gamma-ray emission photopeak of 140.5 keV, an external photon output of 90%, and images recorded using a SPECT, PET, or PET/CT scan. The Organization for Economic Co-operation and Development (OECD) stated in 2019 that worldwide Tc-99m is applied in 85% of diagnostic scans, equating to approximately 30 million patient scans annually [4]. At the 1000 bed Songklanagarind Hospital, Thailand, approximately 5000 scans are performed annually, utilizing Tc-99m mainly for bone scintigraphy [5]. Consequently, as the number of ionizing radiation scans increases, there is growing concern regarding increased exposure levels' impact on medical staff and patients. This increase is a critical component that may result in elevated cumulative radiation exposure for medical personnel [6; 7]. Between 1965 and 1994, a dosimetry database of 109,019 medical workers has established that medical radiation professionals had an elevated risk of lung cancer, with a greater prevalence in males compared to women [8]. Furthermore, in 2004, research published in The Lancet sought to estimate the probability of cancer from X-rays. The findings placed the probability between 0.6% and 1.8%, and in Japan, greater than 3% [9]. However, more recently, some 20 years later, an update by [PERSON], [PERSON], and [PERSON] stated that the average radiation exposure from diagnostic and interventional procedures has now risen significantly, from 0.50 mSv to 2.29 mSv per capita annually [10]. Of concern is that this updated evidence indicates that the cancer risk has doubled, with current exposure increasing the risk by 4.1%, and 8.2% when applying the latest risk estimates. Including cardiovascular effects, the total additional risk now exceeds 10%. Primary data for radiation protection standards derive from studies of individuals exposed to high doses of ionizing radiation. However, a recent study of nuclear workers in France, the UK, and the US reveals a linear increase in cancer rates with radiation exposure, with some evidence suggesting a steeper dose-response relationship at lower doses [11; 12]. In addition, an epidemiological study on populations living near nuclear medicine facilities highlights an increased risk from ionizing radiation, including higher incidences of leukemia, thyroid cancer, genetic disorders, and other health anomalies [13]. According to the linear no-threshold (LNT) model, all exposure to ionizing radiation raises cancer risk proportionally without a predetermined safe threshold, no matter how minor. This concept has proven useful in radiation protection methods. While the LNT model offers a precautionary framework supported by high-dose epidemiological data, its extrapolation to low-dose exposures remain contentious. There is increasing evidence indicating a direct correlation between radiation exposures and rising cancer incidence. The intricacies of biological reactions to low-dose ionizing radiation (LDIR) and epidemiological ambiguities highlight the need for more studies to create more precise risk assessment models [14; 15]. Despite the concerns regarding the potential risks associated with LDIR, there is still a lack of safety awareness within the medical community. For example, a survey of 384 healthcare workers revealed that a high proportion have an inadequate understanding of radiation exposure safety.