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Is Red the New Black? A Quasi-Experimental Study Comparing Perceptions of Differently Coloured Cycle Lanes
Get PDFCities and road authorities in many countries have started colouring their cycle lanes. Some road authorities choose red, some blue, and some green. The reasoning behind this choice is not clear, and it is uncertain whether some colours are superior to others. The current study aims to examine whether coloured cycle lanes are viewed more positively than uncoloured lanes, and whether one of the typically chosen colours is perceived as safer and more inviting to cyclists or more deterring to motorists. Participants were invited to respond to a web survey. Respondents (N = 560) were from the four largest cities in Norway, both genders (42.1% women), and of a wide age range (79.6% between 30 and 70). Depending on cycling frequency, respondents were categorised as either motorist (n = 354) or cyclist (n = 206). All respondents rated different cycle lanes (uncoloured, blue, green, and red) on different attributes. The uncoloured lane was consistently rated least positively, with the lowest scores on visibility, perceived safety for both motorists and cyclist and how inviting it seemed to cycle in the lane. It was also estimated to be the lane that would experience the greatest degree of violation from motorists, in terms of driving or stopping in the cycle lane. The green and red lanes were consistently rated more positively than the blue lane, but whether green or red was preferred depended on whether the respondent had lived a place with coloured cycle lanes. People familiar with coloured cycle lanes, which in Norway are red, rated the red lane more positively than the green lane, while the opposite was true for people who were not used to coloured cycle lanes. The difference in ratings between different colours were similar to, or greater than, the difference from uncoloured to coloured, which implies that it not only matters that a lane is coloured, but also which colour it has.publishedVersio
Park & Ride - Exploring the demand effects of parking charges
Get PDFParking charges can be introduced to control who uses park & ride (P&R) facilities. However, the effect of charges on parking demand is unclear. This paper presents results from a before- and after analysis of fifteen rail based P&Rs in Norway where parking charges were either introduced or increased in 2018. Results show that, in most cases, the demand for parking decreased after the change in pricing, making more parking spaces available for people arriving later than the early morning. However, there is no significant change in the median distance travelled by car to reach the P&Rs.acceptedVersio
Microplastics in road dust – characteristics, pathways and measures
Get PDFThe expected main contributors to road dust-associated microplastic particles (RAMP) are rubber compounds in tyre treads, polymers used to strengthen the bitumen used in road pavement and thermoplastic elastomers used in road marking paints, where the former appears to dominate. The major fraction of RAMP is expected to be found in the runoff from the road and road verge generated during rainfall events. However, even if domestic wastewater treatment plants (WWTPs) are expected to be main recipients of road runoff in urban areas, their presence in the influents or effluents (neither treated water nor sludge) have not been undisputedly documented. There is generally a complete lack of actual evidence to support the extent to which RAMP are removed by existing treatment facilities, and to what degree they are present in road runoff entering these facilities. In addition, the release of tunnel wash water is probably a major point source of RAMP. The estimated treatment efficiencies referred to in this report is based on total suspended solids (TSS) as a proxy for RAMP as well as reported particle size distributions and densities. Sedimentation is expected to be the most important mechanism for the removal of the larger size fractions if sufficient settling time is provided (traditional Norwegian gully pots do not). The report discusses the expected efficiencies of existing treatment solutions, include the roadside treatment plants, gully pots and WWTPs receiving stormwater runoff from urban areas. It also discusses other potential treatment solutions that may be applied, both along the national road network in light of the revised version of handbook N200 by the National Public Roads Administration and in urban areas with limited available space for treatment solutions.Microplastics in road dust – characteristics, pathways and measurespublishedVersio
Effects of roadwork characteristics and drivers? individual differences on speed preferences in a rural work zone
Get PDFWork zone safety from a psychological perspective has received little attention in scientific literature. Therefore, the present study aims to explore the influence of roadwork characteristics and drivers’ individual differences in terms of personality traits and self-assessment of driving skills on speed preferences in a rural work zone. Eight hundred forty-five Norwegian drivers stated their preferred speed for ten pictures of a rural work zone with a 50 km/h reduced speed limit without knowing the speed limit. The results showed that the preferred speeds were greater than the actual reduced speed limit for all pictures. The standard deviations were quite high (from 11 to 14 km/h), indicating that drivers have a rather high variation in preferred speeds. A multilevel model was used to analyse the effects of the variables on speed preference. The results indicated that preferred speeds increased with age, higher scores on the normlessness scale, and higher self-assessment of own driving skills. As for the roadwork characteristics, speed increased with the presence of road markings by 11 km/h, while it decreased by 9 km/h with the presence of road delineators and by 5 km/h with barriers. Implications for respect for the reduced speed limits in work zones were discussed, and recommendations of other countermeasures were presented.acceptedVersio
Crash risk on entrance versus exit zones of road bridges in Norway
Get PDFUsing data from the national register of police-reported crashes and from the bridge register of the Norwegian Public Roads Administration, we estimated rates of single-vehicle crashes on road sections adjacent to road bridges and on different sections of the bridges. Data included all single-vehicle personal injury crashes occurring on or close to road bridges in Norway between 2010 and 2016, a total of 219 crashes. All bridges on state and county roads were included. Crash rate was found to be highest in the approach zone of short bridges (last 50 m before bridge) and lowest in the middle of long bridges. On bridges shorter than about 100 m, crash rate was higher in the first than in the last bridge zone. Total crash rate on bridges was close to the figure for the total road network. However, for the approach to short bridges, crash rate was significantly higher than for the total road network, and for the middle part of long bridges it was significantly lower. A supplementary analysis of in-depth data from 31 fatal crashes including both single-vehicle and multiple-vehicle crashes supported the results from the main analysis. A higher proportion of fatal crashes occurred on approaching or entering a bridge than when leaving the bridge, as seen from the direction of travel of the at-fault vehicle. Concerning countermeasures against bridge accidents, particular attention should be payed to the approach zone and to the design of barriers.acceptedVersio
A systematic cost-benefit analysis of 29 road safety measures
Get PDFEconomic evaluations of road safety measures are only rarely published in the scholarly literature. We collected and (re-)analyzed evidence in order to conduct cost-benefit analyses (CBAs) for 29 road safety measures. The information on crash costs was based on data from a survey in European countries. We applied a systematic procedure including corrections for inflation and Purchasing Power Parity in order to express all the monetary information in the same units (EUR, 2015). Cost-benefit analyses were done for measures with favorable estimated effects on road safety and for which relevant information on costs could be found. Results were assessed in terms of benefit-to-cost ratios and net present value. In order to account for some uncertainties, we carried out sensitivity analyses based on varying assumptions for costs of measures and measure effectiveness. Moreover we defined some combinations used as best case and worst case scenarios. In the best estimate scenario, 25 measures turn out to be cost-effective. 4 measures (road lighting, automatic barriers installation, area wide traffic calming and mandatory eyesight tests) are not cost-effective according to this scenario. In total, 14 measures remain cost-effective throughout all scenarios, whereas 10 other measures switch from cost-effective in the best case scenario to not cost-effective in the worst case scenario. For three measures insufficient information is available to calculate all scenarios. Two measures (automatic barriers installation and area wide traffic calming) even in the best case do not become cost-effective. Inherent uncertainties tend to be present in the underlying data on costs of measures, effects and target groups. Results of CBAs are not necessarily generally valid or directly transferable to other settings.acceptedVersio
Inattention and distraction in fatal road crashes - Results from in-depth crash investigations in Norway
Get PDFDistraction and inattention pose a considerable threat to road safety, not only for car drivers, but also for vulnerable road users. Previous studies show that inattention and distraction are more often contributing factors in severe crashes, compared to less severe crashes. The correlation with severity appears to vary with the type of inattention. The aim of the present study was to conduct a comprehensive mapping of the types of inattention that contribute to fatal road crashes. This was done by exploring data from in-depth investigations of all fatal road crashes in Norway between 2011 and 2015 conducted by crash investigation teams of the Norwegian Public Roads Administration. Crash reports were selected for screening, based on codes indicating inattention as a possible contributing factor. Inattention among at-fault drivers of motor vehicles was found to contribute to almost one out of three fatal road crashes between 2011 and 2015. About one-third of inattention-related crashes involved pedestrians who were hit by motor vehicles, where the driver typically detected the pedestrian too late. Failure to check for information in blind spots or behind other sight obstructions is a typical form of inattention. Distraction by use of mobile phones contributed to between two and four percent of all fatal crashes, while other sources of distraction, within or outside of the vehicle, contributed to about ten percent. Driver inattention may be preventable by a system-oriented approach including a combination of vehicle technology, road and road environment improvements, appropriate signs and markings, education and information, as well as legal measures and enforcement regarding use of mobile phones, in-vehicle sight obstructions, and involvement in other secondary tasks during driving.submittedVersio
Can the use of road safety measures on national roads in Norway be interpreted as an informal application of the ALARP principle?
Get PDFThe ALARP principle, stating that risks should be reduced to a level “As Low As Reasonably Practicable”, is widely known and discussed in risk management. The principle is flexible, as the interpretation of the key concepts of reasonable and practicable can be adapted to different contexts. This paper discusses whether the use of road safety measures on national roads in Norway can be interpreted as an informal application of the ALARP-principle. According to official guidelines, priority setting for major road investments should be based on cost-benefit analysis. Most road safety measures are low-cost projects that have traditionally not been subject to cost-benefit analysis. A use of these measures regarded as reasonable in the ALARP sense may include considerations of cost, efficiency and fair distribution. Data on 328 road safety measures implemented around 2000 is used to evaluate factors influencing their use. It is argued that the use of these measures is consistent with an informal application of the ALARP-principle.publishedVersio
Safety-in-numbers: An updated meta-analysis of estimates
Get PDFSafety-in-numbers denotes the tendency for the number of accidents to increase less than in proportion to traffic volume. This paper updates a meta-analysis of estimates of safety-in-numbers published in 2017 (Elvik and Bjørnskau, Safety Science, 92, 274–282). Nearly all studies find safety-in-numbers, but the numerical estimates vary considerably. As virtually all studies are cross-sectional, it is not possible to determine if safety-in-numbers represents a causal relationship. Meta-regression analysis was performed to identify factors which may explain the large heterogeneity of estimates of safety-in-numbers. It was found that safety-in-numbers tends to be stronger for pedestrians than for cyclists, and stronger at the macro-level (e.g. citywide) than at the micro-level (e.g. in junctions). Recent studies find a stronger tendency towards safety-in-numbers than older studies.acceptedVersio
Mobility, Out-of-Home Activity Participation and Needs Fulfilment in Later Life
Get PDFUsing nationally representative survey of 4723 people aged 67 or older living in Norway, this paper explores the link between wellbeing, out-of-home activity participation and mobility in old age. A basic assumption of this paper is that out-home activities mediated through mobility can contribute to needs fulfillment, and, hence, wellbeing. This study explores the role of preferences, and individual and contextual constraints, in both the overall level of out-of-home activity participation in old age and the level of participation in three specific out-of-home activities (grocery shopping, visiting family or friends, and attending cultural activities). A person’s degree of home orientation is used as an indicator of preference for indoor activities. The findings suggest that age, living status, income, education, holding a driving license, health, social network, centrality of residence, and the quality of the public transport supply have a significant impact on the overall participation level. In addition, the study suggests that the types of constraints vary between travel purposes and the location of activities. Moreover, there is an independent effect of the degree of home orientation on the overall participation level, on the degree of visits to family and friends and on the degree of attending cultural activities, which suggest that people differ in their need for out-of-home activities. However, degree of home orientation has no impact on the degree of grocery shopping, which might imply that grocery shopping is more independent of preferences. The main conclusion from this study is that the extent to which out-of-home activities fulfill needs vary between individuals, depending on their preferences as well as the interplay between individual abilities and resources and contextual conditions.publishedVersio