For the purposes of this guideline, the term “road safety barrier” refers to, but is not necessarily limited to, W-section or Thrie-beam guardrails, concrete barriers such as “New Jersey” or “Tric Bloc” barriers, and wire rope safety barriers.
Recommended practice for delineation of road safety barriers in medians is provided below:
- For grassed medians, where there is more than 1m between the edge of seal and a flexible (wire rope safety barrier) or semi-rigid (W-section and Thrie-beam) barrier system, primary delineation using either EMPs installed as described in the edge marker posts section or RRPMs installed as described in the raised pavement markers section should be used.
Edge marker posts
Raised pavement markers
- For sealed medians, or where there is less than 1m between the edge of seal and the flexible (wire rope safety barrier), semi-rigid (W-section and Thrie-beam) or rigid (concrete) barrier system, primary delineation using RRPMs installed as described in the raised pavement markers section should be used.
- In narrow median installations, where the overall median width between the opposing edgelines is 2m or less, yellow RRPMs may be used as primary delineation.
- Modified EMPs attached to barrier systems should not be used unless the mounting method has been accepted by the Lead Safety Advisor (Roads and Roadsides).
- Wire rope safety barrier (WRSB) in medians should have secondary yellow retroreflective markers at 15m centres along its length, or at the closest value to this for the system post spacing used. The markers should be positioned on the approach face of the posts within 10mm of the top of the posts. Delineation is enhanced when the posts are powder-coated white.
- Secondary delineation retroreflectors on WRSB posts should not exceed 4000mm2 each.
- Where semi-rigid and rigid barrier systems are illuminated by overhead lighting, secondary delineation is not required.
- Where semi-rigid and rigid barrier systems are not illuminated by overhead lighting, secondary delineation, in the form of yellow retroreflective markers at 15m centres may be used. Refer to Figure 2‑12 for an example of a retroreflective marker for use on W-section.
Figure 2‑12
- Secondary delineation retroreflectors on semi-rigid and rigid barriers should not exceed 4000mm2 each.
Table 2‑19: Road safety barrier retroreflector specifications for medians
| Size of retroreflectors |
Colour of retroreflector |
Spacing of retroreflectors;
refer note 1 |
| 4000mm2 (maximum) |
Yellow |
15m |
Table 2-19 note:
- For WRSB, use the closest value to this for the system post spacing used.
Based on the type of road safety barrier used, the type of retroreflector will vary due to the physical differences of the barriers. Figure 2‑12 (a) and (b) illustrates examples of retroreflectors for W-section guardrail and wire rope safety barrier (respectively).
Figure 2‑12:
(a) W-section guardrail retroreflector
(b) wire rope barrier retroreflector
For further details on:
