Adrian Davis

This paper aims to offer novel empirical evidence as to the identification of the most effective Trigger Speeds (TS) for Vehicle-Activated Signs (VAS) in rural areas. To achieve this, an experimental study was carried out in the area of Scottish Borders, UK, in settlements with 20 mph speed limits. To determine the effective trigger speeds for VAS, in terms of reducing vehicle speeds, a comparative quantitative analysis was conducted using traffic and speed data collected during different waves of a traffic survey, for which various TS settings were deployed (24 mph, 28 mph and 35 mph). The descriptive analysis showed that the 24 mph TS threshold seems to be more effective compared to the other TS settings considered, mainly in terms of reducing the 85th percentile speeds. The 28 mph threshold was identified to yield slightly lower mean speeds compared to the other TS settings. Non-parametric and parametric statistical tests were conducted on the basis of approximately 2.8 million speed observations to identify any statistically significant speed differences under various TS settings. Overall, the findings of this study show that the application of VAS in addition to 20 mph speed limits helps reduce vehicle speeds. In particular, setting a TS to remind drivers, especially those driving between 21–24 mph, that they should slow down has led to statistically significant reductions in speeds driven. This provides road safety benefits both from the reduction in kinetic energy in the transport system, any consequent crash-related outcomes, and also by improving perceived safety for all who use and live close to roads where 20 mph speed limits augmented with VAS have been implemented.

This paper aims at delivering new empirical evidence as to the effectiveness of 20 mph speed limits in rural areas. For this purpose, speed and traffic data were drawn from the area of the Scottish Borders, UK, where the local Council led the rollout of a 20 mph speed limit trial in 97 villages and towns from October 2020. This intervention is considered as one of the first of its kind in the UK and overseas, as it was carried out on a large scale, in predominantly rural areas. To evaluate the impact of the 20 mph speed limit on vehicle speeds, we conducted a “before–after” quantitative analysis using traffic and speed data collected in different waves before and after the intervention. The descriptive analysis showed that both mean and 85th percentile speeds reduced directly after the introduction of the 20 mph speed limit (by 3.1 mph and 3.2 mph, respectively), and that such speed reductions were largely maintained even up to eight months after the onset of the intervention. The largest speed reductions were observed in locations with high-speed patterns before the intervention, and especially in those having mean speeds greater than 25 mph before the intervention. Both non-parametric and parametric statistical tests, which were conducted using approximately five million speed observations, showed that the observed speed changes were statistically significant for the vast majority of cases. Linear regression models were also estimated confirming the significant impact of the 20 mph limit on vehicle speeds, while controlling for the influence of traffic volume. Overall, the findings of this study will likely assist in filling an evidence gap regarding the effectiveness of 20 mph speed limits in rural settlements. They can also provide encouragement to those local authorities in the UK and abroad that are currently actively examining the possibility of setting the 20 mph as the default limit in built-up areas.

Starting in an era where three quantifiable impacts of road transport were viewed as the sum total of impacts - casualties and air and noise pollution - from the embryo of the evolving transport and health interdisciplinary field is charted from the perspective of a UK actor in the field. A number of key events are described, from the highlighting of chronic as well as acute health impacts, the damage from sedentary car-based lifestyles, and re-appraisals of prior assumptions. The role of key agencies include the British Medical Association and the World Health Organization as trusted brands in helping to convey new understanding as to the health impacts of road transport as the inter-disciplinary scientific field has expanded.

Transport sector decarbonisation is a Scottish Government policy aim. Recent legislation and funding announcements are beginning a shift away from support for habitual car use. Sustainable transport is augmented by co-benefits of active travel itself through improvements in air quality, safety, and benefits across other sectors. At a workshop, attendees identified the need for further actions including closing down the roads programme and shifting funding to sustainable transport, reducing the need for travel, and a major shift to active travel for journeys under 3 km. Such actions are reflected on in the context of the current coronavirus.

Opportunities for working adults to accumulate recommended physical activity levels (at least 150 min of moderate intensity physical activity in bouts of at least 10 min throughout the week) may include the commute to work. Systematic reviews of interventions to increase active transport suggest studies have tended to be of poor quality, relying on self-report and lacking robust statistical analyses. We conducted a multi-centre parallel-arm cluster randomised controlled trial, in workplaces in south-west England and south Wales, to assess the effectiveness of a behavioural intervention to increase walking during the commute. Workplace-based Walk to Work promoters were trained to implement a 10-week intervention incorporating key behavioural change techniques: providing information; encouraging intention formation; identifying barriers and solutions; goal setting; self-monitoring; providing general encouragement; identifying social support; reviewing goals, and; relapse prevention. Physical activity outcomes were objectively measured using accelerometers and GPS receivers at baseline and 12-month follow-up. The primary outcome was daily minutes of moderate to vigorous physical activity (MVPA). Secondary outcomes included overall levels of physical activity and modal shift (from private car to walking). Cost-consequences analysis included employer, employee and health service costs and outcomes. Six hundred fifty-four participants were recruited across 87 workplaces: 10 micro (5–9 employees); 35 small (10–49); 22 medium (50–250); 20 large (250+). The majority of participants lived more than two kilometres from their place of work (89%) and travelled to work by car (65%). At 12-month follow-up, 84 workplaces (41 intervention, 43 control) and 477 employees (73% of those originally recruited) took part in data collection activities. There was no evidence of an intervention effect on MVPA or overall physical activity at 12-month follow-up. The intervention cost on average £181.97 per workplace and £24.19 per participating employee. The intervention, focusing primarily on individual behaviour change, was insufficient to change travel behaviour. Our findings contribute to the argument that attention should be directed towards a whole systems approach, focusing on interactions between the correlates of travel behaviour. ISRCTN15009100 . Prospectively registered. (Date assigned: 10/12/2014).

Commuting between home and work is routinely performed by workers and any wellbeing impacts of commuting will consequently affect a large proportion of the population. This paper presents findings from analyses of the impact of commuting (time and mode) on multiple aspects of Subjective Well-Being (SWB), including: satisfaction with life overall and the SWB sub-domains of job satisfaction, satisfaction with leisure time availability and self-reported health. Measures of strain and mental health (GHQ-12) are also examined. Six waves of individual-level panel data from Understanding Society (2009/10 to 2014/15) are analysed, providing a sample of over 26,000 workers living in England. Associations between commuting and SWB are identified, paying particular attention to those arising from individual changes in commuting circumstances over the six waves. It is found that longer commute times are associated with lower job and leisure time satisfaction, increased strain and poorer mental health. The strongest association is found for leisure time satisfaction. Despite these negative associations with the SWB sub-domains, longer commute times were not associated with lower overall life satisfaction (except where individuals persisted with them over all six waves). Workers in England appear to be successful in balancing the negative aspects of commuting against the wider benefits, e.g. access to employment, earnings and housing. Differences amongst selected population sub-groups are also examined. The job satisfaction of younger adults and lower income groups are not found to be negatively associated with longer commute times; longer commute times are more strongly negatively associated with the job satisfaction of women compared to men. With respect to mode of transport, walking to work is associated with increased leisure time satisfaction and reduced strain. The absence of the commute, via working from home, is associated with increased job satisfaction and leisure time satisfaction. Overall, the study indicates that shorter commute times and walkable commutes can contribute to improved SWB—particularly through the release of leisure time. But life satisfaction overall will only be maintained if the benefits of undertaking the commute (earnings and satisfactory housing/employment) are not compromised.