Bid to prevent road markings fading again

THE JOHANNESBURGRoads Agency has noted the reports accusing it of using inferior paint for road markings.

In light of this, it would like to assure residents of the City of Johannesburg that the contract for the supply of paint complied with the SA National Standards in terms of composition, quality and colour. Also, the JRA performs quality checks on a regular basis to satisfy itself with the durability and usability of the paint.

There are various common causes of fading road markings, other than the quality of the paint. Drying problems, especially under inclement weather conditions, can compromise the durability of markings. Furthermore, the accumulation of dirt, dust particles and other air pollutants on the surface of paint can cause it to fade.

Staining occurs when these materials become trapped in the paint film. This is particularly the case where dust and dirt are carried onto the road surface. It is essential that all dust is removed prior to painting, which is difficult when applying paint to a road.

Bituminous or creosoted substrates are often the cause of the discolouration of subsequent coats of solventbased (oil-based) paints, which are applied over them. The solvent softens or slightly dissolves the bitumen or creosote, which then discolours the applied paint.

White, solvent-based enamel paints, as well as clear varnishes, are prone to developing a yellow cast with age. This is known as “yellowing” and will occur more quickly in dark areas than areas which get direct or indirect sunlight. This is because UV radiation keeps the resins used in enamel paints and varnishes pure, but in the absence of sunlight, the resins turn an amber colour, causing the yellowing effect.

Acting managing director Mpho Kau has said the JRA remains committed to providing quality roads and road infrastructure and holds itself to high quality standards operationally. The JRA is familiar with the aforementioned root causes of fading road markings, and measures are being taken to mitigate occurrence thereof.

As part of the JRA’s quality assurance, investigations will be conducted on the roads referred to in the article and corrective measures taken. Operations manager: marketing and communications Johannesburg Roads Agency