# Review on Soft Mobility Infrastructure Design Codes
## 2 Codes for Soft Mobility Infrastructure
### Design Features
#### 2.3.5 Stopping Sight Distance  
Stopping sight distance (SSD) is known to affect safety and vehicle operations [52]. Only 5 of the 17 case studies have regulations on SSD for bicycles. Among them, HK (15-25 m) and WA (135 ft or 41.148 m) only have unified requirements for SSD, without detailed classification. AT relates SSD to bicycle speeds which are 15 m for 20 km/h, 25 m  
\begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline \multirow{2}{*}{**Code**} & \multirow{2}{*}{\begin{tabular}{c} **Minimum** \\ **Age-Allowed** \\ \end{tabular}} & \multirow{2}{*}{\begin{tabular}{c} **Helmet** \\ **Until Age** \\ \end{tabular}} & \multirow{2}{*}{\begin{tabular}{c} **Speed** \\ **Limit** \\ **(km/h)** \\ \end{tabular}} & \multirow{2}{*}{\begin{tabular}{c} **Motor** \\ **Power** \\ **(Watts)** \\ \end{tabular} } & \multirow{2}{*}{\begin{tabular}{c} **Passenger** \\ **Permission** \\ \end{tabular} } & \multirow{2}{*}{\
\begin{tabular}{c} **Motor Road** \\ **Speed Limit** \\ **(km/h)** \\ \end{tabular} } & \multirow{2}{*}{
\begin{tabular}{c} **Driving** \\ **License** \\ \end{tabular} } & \multirow{2}{*}{**Mark**} \\ \hline DK & 15 & yes & 20 & - & no & - & no & - \\ \hline AT & 12 & - & 25 & 600 & no & - & no & - \\ \hline GR & 15 & yes & 25 & - & no & 50 & no & - \\ \hline NZ & - & - & - & 300 & no & - & no & - \\ \hline SG & 16 & - & 25 & - & no & - & no & - \\ \hline JP & 16 & - & 20 & - & no & - & no & - \\ \hline ZA & - & - & 25 & - & no & - & no & - \\ \hline TZ & - & - & - & - & no & - & no & - \\ \hline RU & 14 & - & 25 & - & no & 60 & no & - \\ \hline CN & 16 & yes & 25 & 240 & no & - & no & - \\ \hline BJ & - & - & - & - & - & - & - & Illegal \\ \hline HK & 16 & - & 25 & - & no & - & no & - \\ \hline TW & 16 & - & 25 & - & no & 60 & yes & - \\ \hline WA & 16 & - & 16 & - & no & - & no & - \\ \hline NJ & 17 & yes & 30 & - & no & - & no & - \\ \hline DL & 16 & - & 25 & - & no & - & yes & - \\ \hline AD & 16 & - & 20 & - & no & - & no & - \\ \hline \hline \end{tabular}
\end{table}
Table 8: E-scooter usage requirements in countries and regions around the world.  
for 30 km/h, and 40 m for 40 km/h. However, as shown in Figure 8, in ZA and NJ, speed is not only linked to SSD, but also link to slope, with formulas as shown in Formula (4) [35].  
\[D=\frac{2.5V}{3.6}+\frac{0.5(\frac{V}{3.6})^{2}}{2.5+\frac{0.85V}{100}} \tag{3}\]  
where  
D--Stopping sight distance (meter);  
V--Bicycle design speed (km/h);  
G--Gradient (%).  
However, some cyclists prefer to avoid obstacles rather than stop in front of them. Therefore, 'decision sight distance' is used in South Africa. Decision sight distance is defined as the distance at which a driver can, after detecting a hazard or signal, identify it or its potential threat, choose an appropriate speed and path, and perform the required actions safely and effectively [53]. The decision sight distance regulations in South Africa are shown in Table 9, and the difference between stopping and decision sight distance is shown in Figure 9. The stopping sight distance is shorter than the decision sight distance, but they increase at almost the same ratio with speed.  
\begin{table}
\begin{tabular}{c c c} \hline \hline
**Country Code** & **Bicycle Speed Limit (km/h)** & **Decision Sight Distance (m)** \\ \hline \multirow{4}{*}{ZA} & 20 & 45 \\ \cline{2-3}  & 30 & 70 \\ \cline{1-1} \cline{2-3}  & 40 & 90 \\ \cline{1-1} \cline{2-3}  & 50 & 115 \\ \hline \hline \end{tabular}
\end{table}
Table 9: Decision about sight distances for cyclists in ZA.  
Figure 8: Stopping sight distance requirements for bicycles in NJ and ZA.