## 3 Results
#### 3.4.4. [PERSON] et al. Occupational Effective Dose Estimation Algorithm [33]
Double dosimetry significantly enhances safety in radiation environments by accurately estimating a wearer's effective dose and the dose to unshielded body areas, particularly when the lead apron does not provide complete shielding, such as in the case of high-energy radiation or prolonged exposure. Figure 9 presents a comparative analysis of occupational effective dose estimates during \({}^{99\text{m}}\)Tc-MDP bone scintigraphy procedures across seven different dosimetry algorithms. The Clerinx et al. algorithm consistently yields higher dose estimates for labeling, quality control, and syringe preparation, possibly due to more conservative exposure assumptions. In contrast, the Padovani et al. algorithm shows no significant difference in effective doses compared with actual measurements when \(p\) > 0.05. This suggests that the Padovani et al. algorithm aligns more closely with observed dose measurements, while the Clerinx et al. algorithm may reflect a more precautionary approach in estimating occupational exposure [33]. While conservatism in radiation protection can be beneficial for ensuring safety, excessive conservatism may not accurately reflect realistic exposure levels, potentially resulting in unnecessary operational restrictions in clinical settings. However, the NCS algorithm estimated the lowest dose estimates, particularly during syringe preparation and \({}^{99\text{m}}\)Tc-MDP administration. Actual Occupational Effective Dose Measurement at Various Body Parts During \({}^{99m}\)Tc-MDP Bone Scintigraphy Procedure  
Figure 10 illustrates nuclear medicine staff occupational effective dose measurements associated with the preparation, administration, and scanning of patients undergoing \({}^{99\text{m}}\)Tc-MDP bone scintigraphy. As can be seen clearly, the highest occupational effective dose is to the radiopharmacists' hands, Hp(0.07). Their Hp(0.07) equivalent dose during \({}^{99\text{m}}\)Tc-MDP labeling, quality control, and syringe preparation was 2.19 \(\mu\)Sv/h to the right thumb, right palm 1.74 \(\mu\)Sv/h, right eye lens 0.02 \(\mu\)Sv/h, and whole body 0.02 \(\mu\)Sv/h. Whereas the nurse administering the \({}^{99\text{m}}\)Tc-MDP received an equivalent dose of 0.27 \(\mu\)Sv/h  
Figure 8: Comparison of actual occupational effective dose and [PERSON] et al. algorithm [33]. Results are presented as mean \(\pm\) standard deviation (\(n\) = 30), and results marked with \({}^{*}\) indicate a statistically significant difference (\(p\) < 0.05). to the left thumb Hp(0.07), which was in close vicinity to the unshielded needle. The current personal dose limits are whole body Hp(10) \(\leq\) 500 mSv/y, Hp(0.07) skin dose, hands, and feet \(\leq\)500 mSv/y, and the eyes Hp(3) 20 mSv/y (average in 5 years) [43; 44; 45]. Figure 10: Radiation exposure to nuclear medicine personnel during the \({}^{99\text{m}}\)Tc-MDP bone scintigraphy procedure. Dose measurements were taken at various body sites to assess exposure levels, including Hp(0.07) for the right and left thumb, index finger, ring finger, and palm; Hp(3) for the eye lenses of both eyes; and Hp(10) for whole-body exposure. The data are presented as the mean \(\pm\) standard deviation (\(n\) = 30). Figure 9: Effective dose (μSv) measurements during various stages of the \({}^{99\text{m}}\)Tc-MDP bone scintigraphy procedure, including **(A)** Labeling, **(B)** Quality Control, **(C)** Syringe Preparation, **(D)** Patient Administration, **(E)** Imaging, and **(F)** Patient Discharge. Doses are compared across different dosimetry standards: actual measurements (black) and estimates from [PERSON] et al., 2021 (red) [22], NCS (yellow) [40], [PERSON] et al., 2001 (gray) [24; 25], ICRP 60 (green) [31], ICRP 103 (pink) [32], NCRP (orange) [33], and [PERSON] et al., 2008 (blue) [33]. Single and double dosimetry methods are evaluated, with “ns” indicating no significant difference in effective doses between the two methods when \(p\) > 0.05. Results are presented as mean \(\pm\) standard deviation (\(n\) = 30).