Audio tactile profiled roadmarkings

Audio tactile profiled (ATP) roadmarkings, sometimes referred to as rumble strips, are long-life roadmarkings which have raised ribs or mounds oriented perpendicular to the direction of travel and spaced at regular intervals along them (Figure 2‑14). If a driver runs over an ATP marking it will provide an audible and tactile warning. Longitudinal ATP roadmarkings can be used to:
Figure 2‑14

• warn drivers who are suffering the effects of fatigue;
• alert distracted drivers; and
• improve lane discipline.

Safety benefits:

• ATP edgelines reduce run-off road crashes by 30% and head on crashes by 10%.
• ATP centre-lines reduce run-off road to the right crashes by 10-15% and head on crashes by 30%.

Where centre-line and edgeline ATPs are provided, the crash reduction benefits may be less than the sum of each.

Figure 2‑14: Examples of ATP use in New Zealand

ATP roadmarkings are not appropriate for use in a transverse direction across a roadway.  

The extra noise and vibration on top of road surface noise produced by vehicles travelling on an ATP roadmarking is highly dependent on road surface, vehicle type, travel speed, rib height and the spacing between ribs. The optimum ATP roadmarking dimensions have been determined by practical experiments and have proved to be suitable for use in most situations.

The raised ribs of ATP roadmarkings project above surface water on the road. This improves line delineation in wet conditions and when installed in accordance with Specification P30 also renders them more visible on wet nights.

Specification P30: high performance roadmarking

Profiled edgeline markings can also:

• reduce the maintenance required for both the shoulder and edge of seal; and
• provide increased safety for vulnerable road users, both cyclists and pedestrians, by providing a dividing and audible barrier line between the shoulder and the adjacent traffic lane.

ATP roadmarkings are such a proven road safety measure that they are the preferred marking for rural roads of primary collector or higher on the One Network Road Classification and should be used unless there is a specific reason not to install them. 

For additional detailed information refer to:

• Guidelines for audio tactile profiled roadmarkings – for a more detailed discussion of the use of ATP markings;
• Specification M24: audio tactile profiled roadmarkings – contains specifications for installations, set out, general placement and dimensions of markings and maintenance requirements for contractors; and
• Specification P30: high performance roadmarking – requirements for high performance road marking for road safety. Note that P30 updates some material in M24.