## 3 Results  
The display of the structure geometry and visualization at the time of sprinkler head activation in CFAST and FDS is shown in Figure 1.  
The heat release rate for each group of productions and operations without and with sprinkler response are shown in Figure 2.  
The results determined by the previously described methods are summarized in Table 1.  
Figure 1: Visualization of the fire progress in the CFAST and FDS programs, where: **(a)** display of the structure geometry in the CFAST program; **(b)** display of the structure geometry in the FDS program; **(c)** visualization at the time of sprinkler head activation in the CFAST program; **(d)** visualization at the time of sprinkler head activation in the FDS program. The sprinkler head temperature courses determined by the CFAST and FDS models are shown in Figure 3.  
The course of gas temperatures in the vicinity of the platform beams determined by the CFAST and FDS models is shown in Figure 4.  
The temperature course on the surface of the horizontal steel structure determined by the CFAST and FDS models is shown in Figure 5. \begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Method of Calculation**} & \multicolumn{4}{c}{**Group of Productions and Operations**} \\ \cline{2-5}  & **4 th Group** & **5 th Group** & **6 th Group** & **7 th Group** \\ \hline \multicolumn{5}{c}{**Simplified analysis** (empirical calculations)} \\ \hline Sprinkler head activation time \(t_{\text{act}}\) (s) & 216 & 180 & 156 & 132 \\ \hline Maximum ambient temperature at the location of the steel platform ceiling (\({}^{\circ}\)C) & 116 & 118 & 121 & 125 \\ \hline Maximum temperature of the horizontal bearing structure of the platform (\({}^{\circ}\)C) & 30 & 28 & 27 & 26 \\ \hline \multicolumn{5}{c}{**CFAST** (version 7.6.0)} \\ \hline Sprinkler head activation time \(t_{\text{act}}\) (s) & 205 & 140 & 110 & 80 \\ \hline Maximum ambient temperature at the location of the steel platform ceiling (\({}^{\circ}\)C) & 85 & 85 & 86 & 90 \\ \hline Maximum temperature of the horizontal bearing structure of the platform (\({}^{\circ}\)C) & 29 & 28 & 28 & 29 \\ \hline \multicolumn{5}{c}{**FDS** (version 6.7.5)} \\ \hline Sprinkler head activation time \(t_{\text{act}}\) (s) & 190 & 159 & 136 & 113 \\ \hline Maximum ambient temperature at the location of the steel platform ceiling (\({}^{\circ}\)C) & 169 & 145 & 156 & 162 \\ \hline Maximum temperature of the horizontal bearing structure of the platform (\({}^{\circ}\)C) & 43 & 40 & 40 & 39 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Summary of the resulting values of sprinkler protection activation by individual calculation procedures. Figure 2: Heat release rate for each production and plant group, where: (**a**) heat release rate without sprinkler response; (**b**) heat release rate with sprinkler response as determined in the FDS program. Figure 4: Temperature course of gases around the platform beams, they should be listed as: (**a**) temperature course determined by the CFAST model; (**b**) temperature course determined by the FDS model. Figure 5: Temperature course of gases at the surface of a horizontal steel structure, where: (**a**) temperature course determined by the CFAST model; (**b**) temperature course determined by the FDS model. Figure 3: Sprinkler head temperature courses, where: (**a**) sprinkler head temperature determined by the CFAST model; (**b**) sprinkler head temperature determined by the FDS model. The presented results show that the highest sprinkler head activation times were achieved by manual calculations. Shorter sprinkler head activation times are achieved by both the CFAST and FDS models. The sprinkler head activation times determined by both the CFAST and FDS models are highly similar. Lower ambient temperatures below the horizontal ceiling structure due to sprinkler head activation are achieved by simplified analysis and the CFAST model. The calculations show high agreement. The FDS model has been used to determine the highest temperature levels.