How can we know a self-driving car is safe?

Self-driving cars promise solutions to some of the hazards of human driving but there are important questions about the safety of these new technologies. This paper takes a qualitative social science approach to the question ‘how safe is safe enough?’ Drawing on 50 interviews with people developing and researching self-driving cars, I describe two dominant narratives of safety. The first, safety-in-numbers, sees safety as a self-evident property of the technology and offers metrics in an attempt to reassure the public. The second approach, safety-by-design, starts with the challenge of safety assurance and sees the technology as intrinsically problematic. The first approach is concerned only with performance—what a self-driving system does. The second is also concerned with why systems do what they do and how they should be tested. Using insights from workshops with members of the public, I introduce a further concern that will define trustworthy self-driving cars: the intended and perceived purposes of a system. Engineers’ safety assurances will have their credibility tested in public. ‘How safe is safe enough?’ prompts further questions: ‘safe enough for what?’ and ‘safe enough for whom?’

Association of Infrastructure and Route Environment Factors with Cycling Injury Risk at Intersection and Non-Intersection Locations: A Case-Crossover Study of Britain

Objective: This paper examines infrastructural and route environment correlates of cycling injury risk in Britain for commuters riding in the morning peak. Methods: The study uses a case-crossover design which controls for exposure. Control sites from modelled cyclist routes (matched on intersection status) were compared with sites where cyclists were injured. Conditional logistic regression for matched case–control groups was used to compare characteristics of control and injury sites. Results: High streets (defined by clustering of retail premises) raised injury odds by 32%. Main (Class A or primary) roads were riskier than other road types, with injury odds twice that for residential roads. Wider roads, and those with lower gradients increased injury odds. Guard railing raised injury odds by 18%, and petrol stations or car parks by 43%. Bus lanes raised injury odds by 84%. As in other studies, there was a ‘safety in numbers’ effect from more cyclists. Contrary to other analysis, including two recent studies in London, we did not find a protective effect from cycle infrastructure and the presence of painted cycle lanes raised injury odds by 54%. At intersections, both standard and mini roundabouts were associated with injury odds several times higher than other intersections. Presence of traffic signals, with or without an Advanced Stop Line (‘bike box’), had no impact on injury odds. For a cyclist on a main road, intersections with minor roads were riskier than intersections with other main roads. Conclusions: Typical cycling environments in Britain put cyclists at risk, and infrastructure must be improved, particularly on busy main roads, high streets, and bus routes.

Safety in Numbers? A Qualitative Analysis of the 1999 National Firearms Survey

Firearms and their place in American society have been under heavy scrutiny for the past several decades. Previous academic research typically focused on the firearm as a weapon that needs to be regulated, controlled, and the relative fight between various parties concerning second amendment and constitutional rights. However, inadequate scholarly research focuses on the firearm as an abstract, symbolic entity in American culture, and what the firearm represents to Americans in a more complex, abstruse way. This research utilizes the National Firearms Survey (NFS), conducted in 1999, as a mechanism of secondary qualitative analysis to examine the ways in which Americans view their firearms conceptually. After employing qualitative content analysis using data provided by the NFS, we found that Americans seemed to be more concerned about safety and training regarding firearms, as opposed to traditional notions of the firearm as an American symbol of liberty and freedom.