As part of a holistic study into the mechanisms of road dust and of dust control, a simple dust-measuring instrument was developed to objectively measure the dust generated by a vehicle travelling on an unsealed road. The instrument was then used to determine the dust levels on 16 unsealed roads on which members of the travelling public rated the dust on a simple rating scale. Acceptability criteria for dust on unsealed roads were statistically determined from the collected data. Dust levels on a further 30 roads were measured over a period of three months. Samples were removed from the road and subjected to a series of standard and non-standard tests. A simple dust prediction model was statistically determined from the results. Particle size distribution, plasticity characteristics and aggregate hardness were found to be the influencing parameters. The dust prediction model can be used in conjunction with acceptability criteria and a dust palliative selection matrix to prioritise dust control programmes in an unsealed road network. In this paper, a background to the research programme is provided, the development of the dust monitor and the public acceptability criteria are summarised and the development and implementation of the dust prediction model are discussed. (A)
Samenvatting