# Static Factors in Sitting Comfort: Seat Foam Properties, Temperature, and Contact Pressure
## 3 Experimental Campaign
### Experiment 2: The Influence of Seat-Passenger Interface Pressure and Temperature
#### 3.3.2 Influence of Seat and Cover Features
\begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline \multirow{2}{*}{**Seat Type**} & \multicolumn{4}{c}{**Sitting Area**} & \multicolumn{4}{c}{**Sitting Profile Line**} \\ \cline{2-9}  & **Min. (\({}^{\circ}\)C)** & **Max. (\({}^{\circ}\)C)** & **Max-Min (\({}^{\circ}\)C)** & **Avg. (\({}^{\circ}\)C)** & **Min. (\({}^{\circ}\)C)** & **Max. (\({}^{\circ}\)C)** & **Max-Min (\({}^{\circ}\)C)** & **Avg. (\({}^{\circ}\)C)** \\ \hline Comfort/Leather & 28 & 34.1 & 6.1 & 31.8 & 25.2 & 32.9 & 7.7 & 31.8 \\ \hline Comfort/Fabric & 19 & 27.1 & 8.1 & 24.1 & 17.1 & 25.1 & 7.9 & 20.9 \\ \hline Standard/Leather & 26.2 & 32.9 & 6.7 & 30.5 & 23.9 & 31.3 & 7.4 & 27.6 \\ \hline Standard/Fabric & 18.7 & 27.5 & 8.8 & 24.1 & 16.7 & 26.3 & 9.6 & 23.6 \\ \hline \hline \end{tabular}
\end{table} 
Table 13: Temperature records regarding the different seating covers. Figure 11: Pressure distribution profiles of (**a**) current AP comfort seats and (**b**) older AP comfort seats for subject S1. cover seats, meaning the non-influence of seat thickness. For the leather cover, both comfort and standard seats presented minimum temperatures of approximately 28 \({}^{\circ}\)C, whereas the maximum temperature was around 33 \({}^{\circ}\)C (see Figure 12). When considering the fabric seats, the temperature results slightly decreased. Likewise, minimum temperatures of around 19 \({}^{\circ}\)C and maximum temperatures of 27 \({}^{\circ}\)C were found, as illustrated in Figure 13.  
Moreover, it should be noted that regarding the average temperature, fabric covers presented a temperature of 24 \({}^{\circ}\)C, whereas that of leather covers was around 31 \({}^{\circ}\)C. These results contradict the findings of [PERSON] et al. [47], who reported that leather and fabric covers have similar thermic behaviours, and those of [PERSON] et al. [44], once foam thickness did not influence results when using the same cover material. It should be highlighted that the work developed by [PERSON] et al. [47] uses a single subject. Therefore, it is used as a reference but not as a gold standard. Based on the assumption stated by [PERSON] et al. [50] that lower temperatures at the seat-user interface promote higher comfort levels, it can be concluded that fabric covers are more suitable for railway seat applications than leather covers. Results agree with those reported by [PERSON] [64], [PERSON] et al. [65], and [PERSON] et al. [37], where fabric covers revealed superior seat comfort over leather covers. Nevertheless, it should be highlighted that leather covers demonstrated a higher capacity to absorb energy and reduce hardness increases. The latter parameter may be linked to the cover foam connection [18]. Therefore, there is still space for fabric cover improvements and attachment within rail seats. Figure 12: Thermographic profiles of leather cover seats, where (**a**) is the comfort seat (2D, 3D) and (**b**) standard seat (2D, 3D). The present study's findings can be used to improve the static comfort levels of new railway seats. As observed, higher-density foams and fabric covers can increase those. Even so, fabric covers must be improved, as their mechanical properties have been demonstrated to be weaker than those revealed by leather covers. Indeed, the ideal cover would combine the mechanical properties of leather and the thermal properties of fabric.