Rising car ownership and use worldwide is in several respects a threat to the environment. Transport researchers and policymakers have suggested and implemented policy measures to reduce car use and encouraged pro-environmental travel behaviour. The success or failure of these policies depends on a robust understanding of the factors influencing car use behaviour and most importantly situational factors facilitating car use. A sound understanding of the situational factors is the key to the effectiveness and success of car use reduction policies. This study examines the importance of car use facilitating situational factors in the promotion of sustainable mobility in urban areas. Data were obtained in a cross-sectional survey of 691 motorists in Lagos, Nigeria through purposive sampling technique, while the data analysis was done using partial least square structural equation modelling (PLS-SEM). The results indicated car access, time pressure and car use intention contributed 43% explained variance in car use behaviour. Car access had the largest direct effect on car use behaviour, followed by time pressure. Considering all the constructs in the model, car use intention was responsible for most of the variation in car use behaviour. The implications of the results from this study regarding the promotion of sustainable transportation and car use reduction are discussed.

Globally, as many as 50 million road users are injured in road traffic crashes and about 1.35 million of them die. Between 2002 and 2030, global deaths resulting from injuries caused by road traffic accidents are predicted to increase by over 40%. Speeding has a relatively eminent relationship with accident involvement and severity. The experiences of pioneers have revealed that the intelligent speed adaptation (ISA) system reasonably has brought a promising future to speed management and road safety. The findings from the earlier studies disclose that the effect of the advisory ISA on drivers’ behavior, particularly their driving speed choice, is positive and that it is the most desirable system among the drivers. Nevertheless, the system does not have a long-lasting effect, and when the system is removed or deactivated, the effect gradually disappears. Speed limit compliance index (SLCI) is a conceptual method in the form of a novel performance-based indicator and a mathematical formulation that would be potentially a feasible solution to address the abovementioned defect, and it could be an effective countermeasure to improve the efficiency of such a system. This study mainly aims to discuss and illustrate the structure of this method.