AS NZS 1906.3:2017 Retroreflective materials and devices for road traffic control purposes
3.4.4 Impact resistance—Category N and G markers
When a sample of five markers, which have previously successfully undergone the UV exposure test in Clause 3.4.3, are tested in accordance with Appendix H, the markers shall exhibit no permanent damage detrimental to their designed use.
In particular, a marker body consisting of a plastic shell incorporating integrally moulded retroreflective elements, and filled with a body material which is in intimate contact with the back of the retroreflective elements, shall not exhibit—
(a) fracture of the shell extending more than 10 mm from the centre of the point of impact of the hammer, in any direction;
(b) delamination of the rear face of the retro-reflecting element from the body of the marker extending by more than a radius of 20 mm from the centre of the point of impact of the hammer; or
(c) fracturing of the retroreflective element.
3.4.5 Resistance to lens cracking
When a sample of five markers is tested for impact resistance of the lens element the test shall be in accordance with the test outlined in ASTM D4280 Clause 9.4.
In the test, the face of the lens shall show no more than two radial cracks longer than 6.0 mm. There shall be no radial cracks extending to the edge of the abrasion resistant area.There shall be no delamination.
3.4.6 Compressive strength
When a sample of five markers is tested in accordance with Appendix I, the compressive strength shall be not less than the value given in Table 3.7 for the corresponding deformation at failure.
3.4.7 Additional requirements—All markers
Markers shall be essentially free from defects which would affect their appearance or serviceability. The exterior surfaces of the markers shall be smooth with all exposed edges rounded.
NOTE: Users should satisfy themselves that markers do not discolour or retain road grime in their operating environment.
3.4.8 Abrasion resistance (optional)
When determined that Category N or Category G markers claim resistance to abrasion by the addition of a protective surface over the face of the retroreflective element(s) for the purpose of improving durability of the retroreflective element, a sample of five markers having passed the retroreflective test in Appendix A shall be tested.