## 4 Discussion  
This study evaluated the dose and risk to the general public for road transport accidents involving NORM and consumer products containing NORM using the median and maximum value of activity concentration for NORM and consumer products, respectively. The accident scenario was simulated under stability class F for all twelve links of transportation route between Seoul and Gyeongju for the purpose of this study. The maximum population or collective dose during accident transport of source materials (NORMs) occurred in route segment or link-4 and was observed during the accident transport involving monazite shipment. This is because of the higher accident probability rate of link-4 and higher total activity concentration of radionuclides in monazite consignment than the rest of NORMs (source materials). The annual population or collective dose observed in link-4 was \(3.58\times 10^{-5}\), \(1.92\times 10^{-7}\), \(1.56\times 10^{-8}\) and \(3.74\times 10^{-8}\) man-Sv, for monazite, zircon, phosphorus, and bauxite, respectively. The highest individual dose was also observed in link-12. This is because of the highest rate of accident probability and lower population density coupled with a lower number of exposed persons. The individual dose observed in link-12 was \(3.32\times 10^{-5}\), \(1.78\times 10^{-7}\), \(1.45\times 10^{-8}\) and \(3.47\times 10^{-8}\) mSv, for monazite, zircon, phosphorus, and bauxite, respectively. The collective doses were also significantly small and below the annual regulatory limit of 1 man-Sv. The individual dose was also far below the annual regulatory limit of 1 mSv recommended by IAEA. Furthermore, the maximum collective dose occurred in link-4 and was observed in necklace shipment for accident transport involving consumer products containing NORMs. This was also due to the higher accident probability rate in link-4 and higher radionuclide activity concentration in necklace shipment. The annual collective dose was \(3.39\times 10^{-7}\), \(1.96\times 10^{-7}\), \(2.30\times 10^{-8}\), \(7.63\times 10^{-8}\), \(3.43\times 10^{-7}\), \(6.60\times 10^{-8}\), \(3.95\times 10^{-9}\), \(4.31\times 10^{-9}\), \(4.43\times 10^{-7}\),  
Figure 8: Sensitivity analysis result of necklace (consumer product). and 6.03 \(\times\) 10\({}^{-8}\) man-Sv, for latex pillow, mattress, clothing, necklaces, bracelets, amnion patch, cosme, nippers, slippers, and health supplements, respectively. The individual dose was also highest in link-4 due to the highest rate of accident probability of all links and lower population density coupled with lower number of exposed persons. The individual dose in link-12 was 3.15 \(\times\) 10\({}^{-7}\), 1.82 \(\times\) 10\({}^{-7}\), 2.13 \(\times\) 10\({}^{-8}\), 7.09 \(\times\) 10\({}^{-7}\), 3.19 \(\times\) 10\({}^{-7}\), 6.13 \(\times\) 10\({}^{-8}\), 3.66 \(\times\) 10\({}^{-9}\), 4.00 \(\times\) 10\({}^{-9}\), 4.11 \(\times\) 10\({}^{-7}\), and **5.60 \(\times\) 10\({}^{-8}\)** mSv, for latex pillow, mattress, clothing, necklaces, bracelets, amnion patch, cosme, nippers, slippers, and health supplements, respectively. The collective dose and individual dose were insignificantly small and far below the annual regulatory limit recommended by IAEA. The results of analysis of wind rose diagram show the pattern of wind speed and direction from 2010 to 2020 with an average wind speed of 2.4 m/s directing from W to E and from WNW to ESE. Therefore, the residents in these wind directions are at a higher risk of exposure to the released radionuclide aerosol during an accident involving transportation of NORM and consumer products. The sensitivity analysis results indicated the maximum collective doses with **3.58 \(\times\) 10\({}^{-2}\)** and **7.63 \(\times\) 10\({}^{-4}\)** man-Sv at 100% release, aerosol, and respirable fractions for transportation accidents involving monazite (source materials) and necklace (consumer product) shipments, respectively.