The South African National Roads Agency (Sanral) has announced that it will be replacing traditionally smooth painted road markings with new rumble strips – in an effort to increase safety.<\/p>\n
In a statement published on Tuesday (6 November), the agency said that the rumble strips\u00a0\u2013\u00a0also known as sleeper lines, alert strips and wake-up calls\u00a0\u2013\u00a0will first be painted on the shoulder lines and between undivided dual carriageways of the N2 and N3 around Durban.<\/p>\n
“The rumble strips, which replace traditionally smooth painted road markings, cause a tactile vibration and audible rumbling\u00a0to be\u00a0transmitted through the wheels into the vehicle interior.\u00a0<\/span><\/p>\n “The rumble strips are little balls of plastic paint dropped onto the road surface,\u00a0which create a whining or humming noise when traversed by a vehicle tyre,” it said.<\/p>\n According to Sanral, international studies have shown that run-off-road (ROR) crashes can account for a large majority of the fatal single-vehicle crashes.\u00a0<\/span><\/p>\n ROR crashes are due to inattention, speeding, traction loss, over-reaction, crash avoidance and mechanical failure. Rumble strips only prevent ROR crashes due to inattention.\u00a0<\/span><\/p>\n It added that\u00a0New Zealand began using rumble strips since the late 1980s and has reported\u00a0a reduction in\u00a0ROR crashes\u00a0by up to 80%.\u00a0<\/span><\/p>\n \u201cCentreline rumble strips are used on undivided highways to reduce cross-over incidents and\u00a0the\u00a0resultant head-on collisions.\u00a0<\/span><\/p>\n \u201cShoulder rumble strips are used primarily to reduce run-off-road collisions. They alert distracted or drowsy drivers that they are leaving the roadway or crossing the centreline of the road,\u201d it said.\u00a0<\/span><\/p>\n How they work<\/strong><\/p>\n Joos Joubert of Lanino Traffic Markings,\u00a0which has applied the rumble strips,\u00a0said the textured marking called Rumble Drop Markings (RDM) cause a noise when you drive over it and can be seen in the rain at night.\u00a0<\/span><\/p>\n “RDM consist of 25 to 50mm thermo-plastic drops\u00a0that are\u00a03mm high. Normal road markings provide only day-time visibility. If there are no street lights, the road markings are almost invisible.\u00a0<\/span><\/p>\n “On national and provincial roads,\u00a0glass beads are applied on top of the wet paint and provide night time visibility. This effect is accomplished by the refractive index of the beads sending light rays back to the light source.\u00a0<\/span><\/p>\n “These road markings provide very good visibility during day time and night time,\u00a0but as soon as any rain falls on the road markings the water covers the beads and the markings will not be visible at night.”<\/p>\n