The article presents the issue of the implementation of speed management measures on regional roads, whose character requires the use of different solutions than those on national roads. The authors briefly described speed management measures, the conditions for their implementation and their effectiveness with reference to environmental conditions and road safety. The further part of the paper presents selected results of the authors' research into the speed on various road segments equipped with different speed management measures. The estimations were made as to the impact of local speed limits and traffic calming measures on drivers' behaviour in free flow conditions. This research found that the introduction of the local speed limits cause reduction in average speed and 85th percentile speed up to 11.9 km/h (14.4%) and 16.3 km/h (16.8%) respectively. These values are averaged in the tested samples. Speed reduction depends strongly on the value of the limit and local circumstances. Despite speed reduction, the share of drivers who do not comply with speed limits was still high and ranged from 43% in the case of a 70 km/h limit, up to 89% for a 40 km/h limit. As far as comprehensive traffic calming measures are concerned, results show decrease in average speed and 85th percentile speed up to 18.1 km/h and 20.8 km/h respectively. For some road segments, however, the values of average speed and 85th percentile speed increased. It confirms that the effectiveness of speed management measures is strongly determined by local circumstances.

The research presented here evaluated road safety on the road sections included in the Intelligent Traffic Control System of the Podhale Region (ISSRRP) in Poland. This travel time information system consists of a remote traffic microwave sensor, cameras, as well as automatic plate number recognition on national roads with variable message signs and a mobile app to suggest alternative routes in the regional road network. The study analyzed changes in safety caused by transferring traffic volume from national to regional rural and suburban road networks. The assessment of the safety performance was performed with an empirical Bayes study, with periods of three years before and after the implementation of ISSRRP. No changes were identified in the safety performance of the national road network after to the introduction of ISSRRP. However, when the overall network is considered, a potential increase in the number of crashes may be expected, depending on the volume of traffic transferred from national to regional roads, and rural or suburban areas. Therefore, a new approach for system management was proposed, taking into account not only improvement in traffic flow, but also safety performance.

The paper presents the evaluation of effectiveness of non-standard road marking and signs (ES) in speed management. Transverse strips, speed limit signs dedicated to selected lanes, non-standard sign, which inform about slippery pavement at motorway curve during the rain. were analysed. Based on survey, degree of understanding of the content of analysed marking and signs by road users was assessed. Empirical studies allowed for evaluation of change in speed caused by non-standard marking and signs implementation. Results show that non-standard marking and signs can be effective speed management measures. The paper also point out problems in evaluation of ES implementation.

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The paper presents the problem of applying non-typical marking and signs (not included in Polish traffic control guidelines) as a mean to improve traffic performance and safety in Poland. The need for use of such marking and signs was evaluated based on the observed drivers’ behaviour supported by literature study. The results of these analyses confirmed that making the correct decisions by drivers can be difficult and may cause safety hazards, especially in the areas of toll plazas on motorways, which are characterized by a high degree of complexity of traffic organization resulting from various payment system (manual and electronic) and high speed. Studies of non-typical road marking and signs were conducted using surveys and empirical research on drivers’ behaviour, which can be surrogate measures in assessing road safety. The outcome of research confirmed the usefulness of the developed method of the survey for assessing the non-typical marking and signs. Studies have shown that non-typical signs may lead to cognitive deformations, i.e., interpretation of their meaning which is not always consistent with the sender’s intention.