Investigating the effects of Rectangular Rapid Flash Beacons on pedestrian behavior and driver yielding on 25 mph streets: A quasi-experimental field study on a university campus

Rectangular Rapid-Flash Beacons (RRFBs) are safety measures that have become popular in recent years in the USA. Such equipment has demonstrated effectiveness in reducing vehicle speed and conflicts among road users, and increasing drivers’ yielding to pedestrians. However, RRFB effects on pedestrian behaviors are less well documented, and perhaps could produce contraindicated effects in crossing behavior. Specifically, RRFBs may give pedestrians a feeling of protection and induce them to more risk-taking when crossing the road. The current study was designed to investigate drivers and pedestrians’ reactions to a RRFB system installed at a university campus located in Virginia, USA. We deployed (a) field observation, using a multiple pretest/posttest non-equivalent control group quasi-experiment design and (b) interviews of students throughout the project’s multiple time periods. In total, 2454 pedestrians and 1312 drivers were observed and 265 students were interviewed. RRFB installations did not distinguish driver yielding likelihood between sites with or without RRFBs. However, driver yielding overall increased linearly over the five rounds of the study. Whether this was the result of the general presence of RRFBs on campus from the third round to the end of the fifth round is unknown. There is evidence from person interviews that students perceived increased safety for pedestrians over time. Being a RRFB chosen site or actual activation of the RRFBs did not have a significant relationship with pedestrian looking behavior either. The potential consequences of these results as well as the context of RRFB use on a university campus and generally low-speed roads are discussed.     

The effect of fatigue driving on car following behavior

Existing fatigued driving analysis methods mainly focus on lateral driving performance by using the measurements related to the steering wheel or lane position. There is a lack of research on longitudinal car following behavior. In this study, 40 professional drivers are invited to participate in field expressway driving experiment, lasting at least for 6 h. During the test, their performance is measured in terms of their self-reported fatigued driving level according to the Karolinska Sleepiness Scale (KSS), the PERcentage of eye CLOSures (PERCLOS) and the Time Headway (THW). Then the effects of the fatigued driving level on car following behavior are evaluated. The results indicate that the fatigue level (for both KSS and PERCLOS) has significantly impact on THW parameters, including the mean, standard deviation and minimum THW. An increase in KSS and PERCLOS leads to a lower mean and minimum THW. Meanwhile, the standard deviation of THW increases with the increase of KSS and PERCLOS. In conclusion, this study found that a higher fatigue level leads to the driver keeping a smaller THW when following another vehicle and choosing shorter THW to make lane change. More deviation of car following performance was also found with the increase of fatigue level. Therefore, the findings of this study can be used to explain fatigue as one of the major reasons for rear-end collisions. Also, the research findings demonstrate the impact of fatigue on driving behavior in terms of car following performance, which can be used as a measurement for monitoring fatigued drivers.     

An investigation of behaviour and attitudes relevant to the user safety of pedestrian/cyclist shared paths

Bicycle/pedestrian shared paths are an increasingly popular solution to providing cycling infrastructure, despite evidence suggesting safety issues. Improved design and management of shared paths should be informed by understanding of bicyclist and pedestrian behaviour on shared paths, and of relevant safety initiatives (e.g. centreline marking). However, relevant research is lacking. Bicyclist/pedestrian passing events (n = 407) were observed on three relatively busy shared paths in Sydney, Australia – one of them without centreline marking. User characteristics, relevant behaviours and incidents (aggression, near-misses, crashes) were recorded. A tendency toward left-hand travel, as on Australian roads, was stronger for cyclists than for pedestrians, and where centreline was present. Cyclists were often estimated to travel above 10 km/h, a speed limit that has been suggested based on pedestrian safety considerations, but that would be unacceptable for long stretches of commuter cycling. Centreline was associated with lower estimated speeds. Cyclists typically adhered to their responsibility of giving way to pedestrians, but often passed on the left, passed too close, passed without slowing, or passed without warning (e.g. with a bell). Use of mobile telephones and mp3 players is common, particularly amongst pedestrians. Five near collisions were observed, and 53 survey participants reported 2 collisions and 13 near misses. Contributing factors appear to include path users using potentially distracting devices, or straying from the rules of thumb to keep to the left, and to overtake on the right.A survey of cyclists and pedestrians suggested that there are issues with perceptions of space ownership. These results represent an important contribution to the evidence-base for initiatives to improve the safety of shared paths.     

Does avoidance‐attachment style attenuate the benefits of being listened to?

We tested both Rogers's hypothesis that listening enables speakers to experience psychological safety and our hypothesis that the benefit of listening for psychological safety is attenuated by avoidance‐attachment style. We tested these hypotheses in six laboratory experiments, a field correlational study, and a scenario experiment. We meta‐analyzed the results of the laboratory experiments and found that listening increased psychological safety on average but that the variance between the experiments was also significant. The between experiment variance in the effect of listening manipulation on psychological safety exposes a methodological challenge in choosing a research paradigm of good‐versus‐normal listening, as opposed to normal‐versus‐poor listening. More importantly, we found, as expected and across all designs, that the higher the avoidance‐attachment style was, the lower the effect of listening on psychological safety. This finding has implications both for practice and for placing a theoretical boundary on Rogers's theory.     

Applying a longitudinal tracer methodology to evaluate complex interventions in complex settings

Long-running multi-faceted intervention studies are particularly problematic in large complex organizations where traditional methods prove too resource intensive and can yield inaccurate and incomplete findings. This paper describes the first use of, longitudinal tracer methodology (LTM), a realist approach to evaluation, to examine the links between multiple complex intervention activities (processes) and their outcomes on a construction megaproject. LTM is especially useful when the researcher has little control over intervention delivery but has evidence drawn from multiple sources to evaluate the intervention activities effects over time. This methodology has rarely been deployed in complex organizational settings and not on a construction megaproject. This paper presents a case study of its use over a period of three years, on 24 construction sites forming London’s Thames Tideway Tunnel (Tideway) megaproject. The study examines the “transformational” power of occupational safety and health (OSH) interventions across the multiple organizations and supply chains in the megaproject. The study shows how the method can be adapted in-flight to accommodate shifting lines of inquiry as the intervention activities progress and change. This feature along with its resource-efficient operation, make it an attractive option where interventions are likely to have differential effects across multiple sites of enactment.     

Linking safety knowledge to safety behaviours: a moderated mediation of supervisor and worker safety attitudes

The thousands of deaths and disabilities due to workplace accidents and injuries each year emphasize the importance of safety research. Despite occupational safety research that has contributed to identifying antecedents of safety, little is known about why and how safety knowledge leads to safety behaviours and how personal and situational factors interact to promote occupational safety. Using a multilevel, multisource, and time-lagged research design, the present study investigates whether safety knowledge affects safety behaviours through safety attitudes and further tests whether supervisory safety attitudes can impact the strength of these relationships and play a role as moderators of the proposed mediated relationship. Data were collected from workers (N = 177) and supervisors (N = 42) in a construction company in the energy industry at two time points. Results indicate full support for the moderated mediation model, demonstrating that worker safety attitudes partially mediate the relationship between safety knowledge and safety behaviours. Moreover, when supervisors had positive attitudes towards safety, both the direct relationship between worker safety attitudes and safety behaviours and the indirect relationship between safety knowledge and safety behaviours were more positive compared to when supervisors had negative safety attitudes. Theoretical and practical implications for occupational safety are discussed.     

Speed-calming measures and their effect on driving speed – Test of a new technique measuring speeds based on GNSS data

Speeding increases the risk and severity of accidents, especially for vulnerable road users. Hence, minimisation of speeding in built-up areas is vital. Some countries widely use speed-calming measures (SCs). Documentation shows that SCs reduce speeding considerably although various types and designs of SCs affect this reduction. This paper includes studies of the effects from establishment of sinus speed humps of height 10 cm and length 950 cm and chicanes (with a free carriageway width of 5.30 cm and a length between the 0.5 m wide obstacles of 18 m) as a before/after study where the speed pattern after establishing SCs is compared with the one before. Floating Car Data used for analyses includes 3216 trips passing one/more SCs. The main results are that the effect from SCs decreases with the distance from the SCs and that a clear pattern is hard to establish above 75 m from the SC. Despite the apparent absence of more distant effects of each SC, there is an overall reduced average speed on the full length of a road with SCs. Humps reduce the mean speed comparable to the reduction from chicanes, but the speed variation is less reduced near chicanes, and especially prior to the arrival to such SC. Due to different traffic patterns around the two types of SCs, a direct comparison between the effects from humps and chicanes cannot be made. A tentative result at least for the two types of SCs studied is that the chicane results in a reduced effect on speed variation compared to the hump. The chicanes result in increased speed variation prior to the arrival to the SC compared to the humps. Hence, the indication is that chicanes might be less safe than humps due to speed variation although more research is needed especially concerning developing of best practice design for speed reducing devices and other speed-calming measures in built-up areas.     

Bicycle fatalities: Trends in crashes with and without motor vehicles in The Netherlands

Boufous and Olivier (2015) recently found an increasing trend of police-reported cyclist deaths in single-vehicle crashes while a decreasing trend was found for fatal bicycle-motor vehicle crashes. This study sets out to conduct the same trend analyses for the Netherlands using causes of death statistics. The results show that for 1996–2014, the number of cyclist deaths in motor vehicle collisions per km cycled (i.e. the risk) has declined by 3.8% per annum (95% CI: −4.6%, −3.0%) while the risk of cyclist deaths in crashes without motor vehicles increased by 7.0% per annum (95% CI: 5.5%, 8.7%). The large majority of cyclist deaths at the beginning of the study period were due to bicycle-motor vehicle crashes. By 2014, however, the share with motor vehicles was only slightly higher than the share without motor vehicles. We also conducted trend analyses controlling for age by stratifying into nine age groups. After controlling for age, the average annual decrease of cyclist deaths in crashes with motor vehicles was 5.4% (95% CI: −6.0% to − 4.7%). The average annual increase of deaths in crashes without motor vehicles was 4.4% (95% CI: 3.1–5.7%). These trends are more favourable than those without controlling for age which can be explained by more cycling among the elderly who have an elevated risk. We conclude that, similar to Australia, cyclist deaths following motor vehicle crashes in the Netherlands have decreased while deaths without motor vehicles have increased.     

Psychosocial safety climate (PSC) and enacted PSC for workplace bullying and psychological health problem reduction

Bullying at work has profound effects on both the individual and organization. We aimed to determine if organizational psychosocial safety climate (PSC; a climate specific to worker psychological health) could reduce workplace bullying and associated psychological health problems (i.e., distress, emotional exhaustion, depression) if specific procedures were implemented (PSC enactment). We theorized that the PSC enactment mechanism works via psychosocial processes such as bullying mistreatment climate (anti-bullying procedures), work design (procedures reduce stress through work redesign), and conflict resolution (procedures to resolve conflict). We used two-wave national longitudinal interview data from 1,062 Australian employees (Australian Workplace Barometer project) and structural equation modelling to explore relationships over 4 years. PSC Time 1 predicted enacted PSC and reduced bullying 4 years later. PSC Time 1 was indirectly negatively related to poor psychological health Time 2 through enacted PSC and bullying. Bullying Time 1 also gave rise to procedures which in turn reduced bullying Time 2. Our findings suggest a multi-component approach to prevent or reduce bullying. Procedures (to reduce psychosocial hazards) that emerge in a high PSC context are more comprehensive than those triggered by bullying (reactive procedures), and can therefore be more effective in reducing worker mistreatment. Building PSC and a strong climate for psychological health, and enacting PSC is fundamental to bullying prevention.     

The implications of low quality bicycle paths on the gaze behaviour of young learner cyclists

In a recent study, Vansteenkiste et al. (2014) described how low quality bicycle paths cause an apparent shift of visual attention from distant environmental regions to more proximate road properties. Surprisingly, this shift of visual attention was not accompanied by an adaptation in cycling speed. The current experiment investigated to what extent these findings are applicable for young learner bicyclists (aged 6–12 years). Since young learner bicyclists do not yet have mature visual and motor skills, it was expected that the implications of a poor road surface would be larger for them than for experienced adult bicyclists. In general, children looked less to the road and more to task irrelevant regions, but the magnitude of the shift of visual attention when cycling on a low quality bicycle track was similar to that of adults. Although children cycled slower than adults, they did not cycle slower on the low quality track compared to the high quality track. Overall, our results suggest that children displayed a different visual-motor strategy than adults, characterized by lower cycling speeds and a different visual behaviour, and that they responded in a similar way to a low quality bicycle path as adults.