The guessability of traffic signs: effects of prospective-user factors and sign design features

This experiment investigated the relationships between the characteristics of prospective-users of traffic signs (people who will use the signs in the future) and the guessability of traffic signs, and also examined the effects of sign design features on the guessability of traffic signs. Forty-one Hong Kong Chinese subjects guessed the meanings and rated the sign features of 120 Mainland Chinese signs. Contrary to expectation, cycling experience and previous experience with sign information had no effect on sign guessing. Males and females with similar education level had similar guessing performance. Previous experience of visiting Mainland China was a significant predictor of guessing performance. Family ownership of a vehicle was associated with guessing performance for subjects who intended to become a driver and for those with car game experience. Subjects who claimed to pay attention to traffic signs in daily life performed better at sign guessing than those who did not. Traffic incident experience did not seem to enhance awareness of, or knowledge about, traffic signs. Guessability of a sign varied with the five design features of; familiarity, concreteness, simplicity, meaningfulness, and semantic closeness of the sign. Semantic closeness was the best predictor of guessability score, followed by familiarity, meaningfulness, concreteness, and simplicity. In order to design more user-friendly traffic signs and effective ways of using them, it is suggested that designers develop and evaluate signs according to the relative importance of the five sign features.     

Comprehensibility of traffic signs among urban drivers in Turkey

Traffic signs are commonly used traffic safety tools, mainly developed to provide crucial information in a short time to support safe drive; but the success depends on their comprehensibility by the drivers. Also, a sudden change in the traditionally used and accepted signs can cause significant safety problem, as in the case of cancellation of red oblique bars in 2004 as a part of the European Union Harmonization Process of Turkey.     

Differential effects of traffic sign stimuli upon speeding in school zones following a traffic light interruption

Motorists whose journey has been interrupted by signalized traffic intersections in school zones resume their journey at a faster vehicle speed than motorists who have not been required to stop. Introducing a flashing “check speed” sign 70 m after the traffic intersections counteracts this interruptive effect. The present study examined which aspects of a reminder sign are responsible for reducing the speeding behavior of interrupted motorists. When a sign that combines both written text and flashing lights was introduced, interrupted motorists did not speed, traveling on average 0.82 km/h below the 40 km/h speed limit when measured 100 m from traffic intersections. Alternatively, when only the flashing lights were visible the interrupted motorists sped 3.36 km/h over the 40 km/h speed limit. Similar vehicular speeds were observed when only the written text was visible and when no sign was present (7.67 and 7.49 km/h over the 40 km/h speed limit, respectively). This indicates that static reminder signs add little value over the absence of a school zone reminder sign; the presence of both cues is necessary to fully offset the interruptive effect. This study also highlights the benefit of using exogenous visual cues in traffic signs to capture drivers’ attention. These findings have practical implications for the design and use of traffic signs to increase compliance with posted speed limits.     

Compliance of Ultra-Orthodox and secular pedestrians with traffic lights in Ultra-Orthodox and secular locations

Following a previous study that revealed the disobedience of Ultra-Orthodox citizens, as compared to secular citizens, of traffic lights at crosswalks, the present study examined the road habits of 995 Ultra-Orthodox and secular pedestrians in neighboring Ultra-Orthodox and secular cities. Using an observation grid designed specially for this study, the pedestrians were observed at two crosswalks – one in an Ultra-Orthodox city and one in a secular city – as far as similar traffic parameters, using a logistic regression. The tendency to cross on a red light was assessed as a function of estimated age, gender, religiosity, location (religious/secular), the duration of the red light, the number of vehicles crossing and the number of pedestrians waiting at the curb. Ultra-Orthodox pedestrians committed more violations than secular pedestrians did, and there were more road violations in the Ultra-Orthodox location than there were in the secular location. Fewer traffic violations were committed by “local” pedestrians (Ultra-Orthodox pedestrians in the Ultra-Orthodox location and secular pedestrians in the secular location) than by “foreigners” (Ultra-Orthodox pedestrians in the secular location and secular pedestrians in the Ultra-Orthodox location). The odds of crossing on a red light decreased as a function of both the number of people waiting at the curb and the number of vehicles. Consistent with previous research, males crossed on red much more than females did, regardless of religiosity and location. Our discussion focuses on theoretical and practical explanations of the findings.     

Gender differences in road traffic injury rate using time travelled as a measure of exposure

There is no consensus on whether the risk of road traffic injury is higher among men or among women. Comparison between studies is difficult mainly due to the different exposure measures used to estimate the risk. The measures of exposure to the risk of road traffic injury should be people's mobility measures, but frequently authors use other measures such population or vehicles mobility. We compare road traffic injury risk in men and women, by age, mode of transport and severity, using the time people spend travelling as the exposure measure, in Catalonia for the period 2004–2008. This is a cross-sectional study including all residents aged over 3 years. The road traffic injury rate was calculated using the number of people injured, from the Register of Accidents and Victims of the National Traffic Authority as numerator, and the person-hours travelled, from the 2006 Daily Mobility Survey carried out by the Catalan regional government, as denominator. Sex and age specific rates by mode of transport and severity were calculated, and Poisson regression models were fitted. Among child pedestrians and young drivers, males present higher risk of slight and severe injury, and in the oldest groups women present higher risk. The death rate is always higher in men. There exists interaction between sex and age in road traffic injury risk. Therefore, injury risk is higher among men in some age groups, and among women in other groups, but these age groups vary depending on mode of transport and severity.     

Influence of deficiencies in traffic control devices in crashes on two-lane rural roads

One of the main objectives of all public administrations is reducing traffic crashes. To this end, Road Safety Inspections (RSI) stand out as a key measure. Signaling roads is one of the foremost tasks of RSI. A road that is improperly or poorly signaled can lead to incorrect placement or maneuvers of vehicles and ambiguous situations that can increase the risk of crashes. This paper analyses the relationship between road crashes in two-lane rural highways and certain deficiencies in signaling. The results show that deficiencies such as ⿿incomplete removal of road works markings⿿ or ⿿no guide sign or in incorrect position⿿ are the ones associated with a higher probability of crashes in two-lane rural highways. In view of these results, governmental agencies should verify that the original conditions of a highway are re-established after any construction work is completed. They should also continuously follow up on the signaling of this type of highway in order to maintain optimal conditions.     

Distribution and characteristics of road traffic crashes in the Chaoyang District of Beijing, China

In many developing urban settings, economic growth and motorization are coupled with increasing rates of road traffic injuries (RTIs). By highlighting typical sites and circumstances at/in which car crashes occur, more specific targets for prevention can be identified. The study is based on police data for a 1-year period and covers the Chaoyang District, the biggest district of Beijing City. Focus is placed on crash patterns and their distribution by types of road and areas. Both fatal and non-fatal crashes are considered (n=754). In the main, the crashes occurred in relatively favorable driving circumstances (e.g., sunny weather, flat and straight roads, asphalted roads, and good traffic signals and road markings). They were also quite evenly distributed over time of day, day of week and season. Five crash patterns were highlighted, of which three were strongly associated with specific areas and four with specific types of road. The study supports the idea that type of road and RTI severity or pattern are closely related. It contributes to the development of context-relevant prevention measures aimed at reducing road crashes and minimizing their consequences and also supports safe planning of the road traffic environment.