15-3 Minimum Sight Distances at Railway Level Crossings – Tables and Figures

​​​Table 15-3a: Required approach sight distances at railway level crossings1

Vehicle approach speed (​km/h)2, 3
Approach distance (A)4
Required approach visibility along tracks (B)4,5
Signs only
Alarms only6
Alarms and boom gates6
20
31m
318m
Approach Sight Triangles not applicable in this situation
30
50m
282m
40
73m
274m
50
100m
278m
60
130m
287m
70
164m
300m
80
208m
314m
90
251m
330m
100
298m
357m
110
350m
376m
1 This table is based on the sighting distance formula used in New Zealand Transport Agency Traffic Control Devices Manual 2008, Part 9 Level Crossings and in the Australian Level Crossing Assessment Model (ALCAM). Distances are conservative and are derived from:
  • A train speed of 110 kph and a single set of rail tracks
  • A fall of 8 % on the approach to the level crossing and a rise of 8 % at the level crossing
  • 25 m design truck
  • 90° angle between road and rail
  • Other parameters as specified in New Zealand Transport Agency’s Traffic Control Devices Manual 2008, Part 9 Level Crossings – Appendix B
2 Speed restrictions are not used in New Zealand around level crossings
3 The 85th percentile road vehicle speed shall be adopted. This speed is typically estimated at the point at which a driver would first see the level crossing signs/alarms and begin to look for trains. Where this is not known, the sign-posted road speed + 10% shall be used
4 Refer to Figure 15-3b for how to define the Approach Sight Triangle using distance (A) and (B).
5 The distances in this table apply to a single set of rail tracks only. For each additional set of tracks add 25m to the distance (B).
6 Railway Level Crossings controlled by alarms or boom gates do not require approach sight triangles because they provide active warning signals of approaching trains.

Figure 15-3b: Measuring approach sight triangles at railway level crossings


Table 15-3c: Required restart sight distances for railway level crossings1

Required approach visibility along tracks (C)2.3
Signs only4
Alarms only4
Alarms and boom gates4
677m
677m
60m
1 This table is based on the sighting distance formula used in New Zealand Transport Agency Traffic Control Devices Manual 2008, Part 9 Level Crossings and in the Australian Level Crossing Assessment Model (ALCAM). Distances are conservative and are derived from:
  • A train spee​​d of 110 kph and a single set of rail tracks 
  • A fall of 8 % on the approach to the level crossing and a rise of 8 % at the level crossing
  • 25 m design truck
  • 90° angle between road and rail
  • Other parameters as specified in New Zealand Transport Agency’s Traffic Control Devices Manual 2008, Part 9 Level Crossings – Appendix B
2   Refer to Figure 15-3d for how to define the Restart Sight Triangle using distance (C).
3   The distances in this table apply to a single set of rail tracks only. For each additional set of tracks add 50m to distance (C).
4   Type of Railway Level Crossing control.

Figure 15-3​d: Measuring restart sight triangles at railway level crossings

 

 

Page reviewed: 25 Jan 2019 2:27pm