The engineering process of setting speed limits is specialised and considers a wide array of factors, including the number of crashes, existing engineering interventions, types of vehicle, road users, vehicle volumes, modes of transport, road alignment, socio-economic and human factors, as well as the road environment in general. Fieldwick and De Beer (1988) emphasised that an urban speed limit is a necessary and effective road safety tool. Speed limits convey important information to drivers as to what the safe maximum speed is for a certain road considering the prevailing conditions. Roads have prescribed speed limits that fit the individual road's primary function. These limits are determined by considering the quality and type of road, the type and mix of road users and traffic, and the surrounding environment.
Reference:
Venter, K. 2009. Informal methods of social control: managing speed behaviour on SA roads. Civil Engineering, Vol. 17(8), pp 30-35
Venter, K. (2009). Informal methods of social control: managing speed behaviour on SA roads. http://hdl.handle.net/10204/3864
Venter, Karien "Informal methods of social control: managing speed behaviour on SA roads." (2009) http://hdl.handle.net/10204/3864
Venter K. Informal methods of social control: managing speed behaviour on SA roads. 2009; http://hdl.handle.net/10204/3864.