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Figure 6-1: Example of layout design related to crossings (source: RilSA, 2003) 6.6.1 Pedestrian crossings

It is recommended to have different markings of crossings with signal control and without. Parallel dash lines can be used at signalised crossings, while zebra crossings can be used without signal control, pedestrians have priority when crossing at zebra crossings.

Pedestrian crossings should be established at each leg of the intersections unless certain restrictions of safety problems or other reasons, because pedestrians tend to cross directly from the origin to the destination, long detour should be avoided. If crossing at one leg is prohibited, guard rails must be deployed around the street corners.

Crossings should be located as near as the edge of the parallel road as possible in order to have better inter-visibility between pedestrians and motorists. If right turning traffic is released together with the parallel pedestrians, the crossing must be set back for 5.0 m to 6.0 m from the edge of the carriage way in order to accommodate a right turning passenger car. The minimum distance between pedestrian crossing and stop line is 1.0 m.

A standard width of pedestrian crossings is 4.0 m, the minimum width is 3.0 m. When bicycles are jointly controlled with pedestrians, a separate crossing for bicycles should be established and the width should be no less than the width of bicycle lanes. When the crossing is wider than 8.0 m, another signal head is required.

Waiting area at the curb sides and islands (refuge islands in the middle and triangular islands) should be sufficient, generally the design density is 2~3 ped/m2 and 1 bicycle/1.5 m2. If waiting area isn’t enough, cycle length or pedestrian red time have to be shortened.

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In order to prevent pedestrians from crossing at undesired sites, guard rails should be deployed along sidewalks or refuge islands under following conditions:

• main streets with high vehicle volume and high speed

• major pedestrian generators(e.g. school, supermarket etc.) are located nearby intersections

• bus stops located on sidewalks nearby intersections;

• crossing at one or more legs of intersections are prohibited;

• refuge islands of staggered crossings. 6.6.2 Refuge islands

Refuge islands should be established at wide streets where the crossing distance covering motorised lanes exceeds 15.0 m. The minimum width of refuge islands is 1.8m, the area should be sufficient to accommodate pedestrians and cyclists under certain signalisation at successive crossing (see 6.9.3), too small refuge islands have to be expanded, for example, by using staggered crossings or even at the expense of reducing carriageway width or the number of lanes.

The illuminated bollards or reflection facilities are necessary to be provided to minimize the potential of drivers running into the refuges in darkness.

6.6.3 Triangular islands

It is necessary to establish triangular islands at skewed intersections (with an entry angle smaller than 70˚ or larger than 108˚) in order to improve visibility of motorists.

Triangular islands can also be used at perpendicular intersections with high volume of right turning vehicles. A well designed triangular island can on the one hand optimize the right-turning motorist view of pedestrians and of vehicles to his(her) left, on the other hand, reduce pedestrian crossing distance and consequently clearance time (Figure 6-1).

Zebra crossing is recommended to connect triangular islands and curb sides in order to avoid additional waiting time for pedestrians, signs waning drivers to yield to pedestrians should be erected. If more than one right turning lane exists or speed of right turning is high, signalised crossing should be established for safety sake.

6.6.4 Traffic calming facilities

Small curb radii are beneficial to reduce pedestrian crossing distance and avoid too smooth right turning movement, generally a curb radius of 10 m ~15 m is recommended.

Other traffic calming facilities including curb extension, raised crossings can be used at intersections in residential area in order to reduce vehicle speed and make it more possible for motorists to yield to pedestrians. Curb extensions should only be used where there is a parking lane and shouldn’t extend more than 1.8m from the curb, the turning needs of larger vehicles, buses also need to be considered.

6.6.5 Transit bus stops

When bus stops are designed on the sidewalk, it is better to locate bus stops at the far side of intersections when passenger volume is high and make it as near to the crossing as possible, since pedestrians may cross behind the bus, visibility between pedestrians and oncoming traffic can be enhanced. Guard rails along the sidewalk are necessary so as to guide pedestrians to cross at the designated crossing.

When transit stops are designed in the middle (e.g. BRT stops), the bus stop is recommended to be integrated with crossings, shown in Figure 6-2.

Figure 6-2: integrated design of bus stops and crossings at signalised intersections (source: RAS-K-1, 1988) 6.6.6 Signs

Signs to prompt turning drivers to yield to pedestrians are necessary to be erected at intersections with permissive turn phasing and at zebra crossings which are connected to triangular islands. Signs mounted adjacent to or integral with pedestrian push button are required to explain purpose and use of the push button. Other signs providing pedestrians with information of meanings of pedestrian signals, warning pedestrians of turning traffic can be applied as well in order to inform pedestrians of safe behaviour.

6.7 Guidelines on pedestrian signal indication