# A Method for Evaluating the Spatial Layout of Fire Stations in Chemical Industrial Parks
## 3 Results and Discussion  
According to the method proposed in this article, an analysis was conducted regarding the rescue paths of Park X, resulting in the construction of a rescue path network, as illustrated in Figure 1. The network was used to simulate common road conditions, while the actual road restrictions, such as the presence of one-way lanes and red lights, were not considered [47]. The figure also shows the locations of the fire stations situated within the park, along with the analysis results of the PTBRs. Through the analysis, it was found that Park X has a total of fifty-four PTBRs and two fire stations, which will be referred to as Fire Station A and Fire Station B, respectively. It can be observed from Figure 1 that the roads within Park X are highly irregular, and that the rescue routes are relatively complex. Furthermore, the distribution of PTBRs is uneven, with some areas having a high concentration of PTBRs and others having sparse PTBRs. In fact, most chemical industrial parks face similar situations. Using the fire risk assessment method proposed in this article, the fire risk scores for the 54 PTBRs in Park X were calculated. The average fire risk score for all PTBRs in Park X is 24.5, with a standard deviation of 28.5. Referring to the classification criteria for the fire risk levels provided in Table 4, Park X has one PTBR with a high fire risk level, 42 PTBRs with a medium fire risk level, and 11 PTBRs with a low fire risk level. The distribution of fire risk levels for all PTBRs in Park X is shown in Figure 2. Based on the fire risk assessment results obtained for each PTBR, the required rescue time for each PTBR can be determined according to Table 5. For instance, the required rescue time for a high-risk PTBR is 3 min. Based on the rescue path network shown in Figure 1, the minimum distance paths from each PTBR to each fire station were separately calculated. Through dividing these minimum distance paths by the estimated speed of fire engines (50 km/h in this article),  
Figure 1: Rescue road network; PTBR and fire station locations in Park X.  
Figure 2: Fire risk assessment results for Park X.  
the estimated rescue time from each PTBR to each fire station was obtained. For a specific PTBR, the estimated rescue time to reach Station A was compared with the estimated rescue time to reach Station B, and the smaller one was selected as the minimum estimated rescue time. The minimum estimated rescue time for each PTBR was then compared with its corresponding required rescue time, as illustrated in Figure 3. If the minimum estimated rescue time satisfies the required rescue time, the PTBR is considered effectively covered by the fire station. In other words, the PTBRs effectively covered by the fire station are located below the line y = x in Figure 3. It can be observed from Figure 3 that four PTBRs are not effectively covered by fire stations. The diagonal shadow area in Figure 4 represents all the effectively covered PTBRs and the corresponding regions they represent. Using Equation (3), the coverage rate of fire stations in Park X is calculated to be 92.6%. This exceeds the evaluation standard of 80% mentioned in this article, indicating that the fire station coverage rate of Park X meets the requirement. The \(x\)-axis of Figure 5 represents the estimated rescue time from each PTBR to Station A, while the \(y\)-axis represents the estimated rescue time from each PTBR to Station B. The required rescue time standards for different fire risk levels are plotted on both axes. In  
Figure 4: The area effectively covered by fire stations in Park X.  
Figure 3: Comparison between the required and estimated rescue time. the figure, when a PTBR falls within the green area (including the yellow and red areas within it), it indicates that the estimated rescue time for the PTBR to reach both fire stations is less than 8 min. For a PTBR with a low risk level, being within this area means it is covered by both fire stations.