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Nattstøy og søvnforstyrrelser. Utredning av indikator og grunnlag for nasjonalt mål for reduksjon av søvnforstyrrelser på grunn av støy
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Effects on accidents of changes in the use of studded tyres in major cities in Norway: A long-term investigation
Get PDFThis paper reports the findings of two studies made eleven years apart in Norway (Fridstrøm, 2000, Elvik and Kaminska, 2011) to evaluate effects on accidents of changes in the use of studded tyres in major cities in Norway. The first study covered the period from 1991 to 2000, the second study covered the period from 2002 to 2009. In both these periods, large changes in the percentage of cars using studded tyres were found in the cities that were included in the study. There was, in most cities, a tendency for the use of studded tyres to go down. Effects of these changes on injury accidents were evaluated by means of negative binomial regression models, using city and day as the unit of analysis, and including more than twenty explanatory variables in order to control for confounding factors. The effects of changes in the percentage of cars using studded tyres were well described by an accident modification function (dose–response curve), relating the size of changes in the number of accident to the size of the change in the use of studded tyres. Accidents during the season when the use of studded tyres is permitted were found to increase by about 5 percent if the use of studded tyres was reduced by 25 percentage points (e.g. from 50 to 25 percent) and to decline by about 2 percent when the use of studded tyres increased by 20 percentage points.submittedVersio
Impeding lone-wolf attacks: lessons derived from the 2011 Norway attacks
Get PDFLone-wolf terrorism is often more difficult to detect through intelligence due to limited communication between plotters. This study addresses this problem by spelling out an alternative method for impeding such attacks. It combines crime scripts, situational crime prevention and rational planning to study how to impede attacks such as the 2011 Norway attacks. Analyzing the transport issues in these attacks demonstrates that some sort of entry control and measures facilitating the evacuation in case of prolonged attacks might reduce the harm.publishedVersio
Knowledge-based land use and transport planning? Consistency and gap between ‘state-of-the-art’ knowledge and knowledge claims in planning documents in three Scandinavian city regions
Get PDFThe central concern of this paper is the relationship between research-driven “state-of-the-art” knowledge, and knowledge claims made in practice, in planning for sustainability. The paper approaches this topic from a critical realist perspective, which is used to provide criteria for positing “state-of-the-art” knowledge validity, and assessing the quality of situated knowledge claims in planning practice. In this way the paper contributes to debates about an ontological turn in planning knowledge. By reviewing key planning documents in three Scandinavian city regions, the paper shows that the knowledge claims about travel behavioral impacts of proposed land use and transport infrastructure presented in the documents are, to varying extents, in accordance with “state-of-the-art” academic knowledge on these topics. Some long-standing “planning myths” are encountered in the investigated planning documents. In one of the cities, residential and workplace location close to suburban public transport stops is highlighted as a traffic-reducing measure, rather than proximity to inner-city concentrations of jobs and other facilities, and density is discussed at a neighborhood scale rather than at a city scale. In all three cities, planning documents depict road capacity increases as having no traffic-generating effect. These latter claims are used in support of more decentralized land-use patterns and considerable road development. Since the likelihood of achieving sustainability goals relies heavily on whether the measures chosen are productive or counter-productive, knowledge obviously matters. A stronger focus on how well suited proposed strategies for spatial development are to produce their purported outcomes should be welcomed in planning research and practice.acceptedVersio
Challenges of improving safety in very safe transport systems
Get PDFThis paper discusses some challenges that may arise when trying to improve safety in systems that are already very safe. Railways in Norway are used as a case of a very safe transport system. The following challenges in improving safety are discussed: (1) A low number of accidents per unit of time makes it difficult to estimate both the current level of accident risk and changes over time in the level of accident risk. (2) Partly as a result of the low number of accidents, incident reporting has been introduced; however it is not always clear how to interpret changes in the number of incidents reported. One reason for this is that some incidents have a low potential for developing into accidents, because multiple safety barriers (defences-in-depth) stop incidents from escalating. (3) Knowledge of the effectiveness of safety barriers combined with a good safety record may lead to excessive reliance on the safety barriers and behavioural adaptation to them. The existence of these challenges is illustrated by means of data from Norwegian railways. It is discussed whether attaining a very high level of safety may lead to loss of information and loss of motivation that may slow down further progress in improving safety.submittedVersio
Free Fares Policies: Impact on Public Transport Mode Share and Other Transport Policy Goals
Get PDFThis article investigates the merits of free public transport as a means to achieve a number of transport policy objectives, including mode shift towards public transport. It outlines some political and societal motivations behind proposals for free and low fare schemes, and presents key economic principles for public transport pricing. Examples of free fare schemes mainly from Europe are summarised and their impacts synthesised. Although free public transport at a first glance may seem attractive both from economic, social and environmental perspectives, the message learnt from a number of schemes is that free public transport offers poor goal achievement in all these respects, and at a high cost. The main effect is a huge growth in patronage, up to 13-fold increase is reported, of which the larger brunt is shifted from walk/cycle, or induced. The effects on car traffic levels are marginal and typically they are offset already after a few years’ traffic growth. Successful free public transport schemes are those whose goal is mainly to grow patronage. Congestion relief, social and environmental benefits are best achieved with more targeted measures, or in combination with such measures.publishedVersio
A survey of vehicle fires in Norwegian road tunnels 2008-2011
Get PDFNorway is one of the countries that constructs most road tunnels, and there are well over 1000 in the country today. The aim of this study is to map the prevalence and describe the characteristics of vehicle fires in Norwegian road tunnels 2008–2011. The average number of fires in Norwegian road tunnels is 21.25 per year per 1000 tunnels, and the average number of smoke without fire (SWF) is 12.5 per year per 1000 tunnels. The study provides four main results. The first is that the fires generally did not involve harm to people. This has also been reported in previous Norwegian research. The second finding is that heavy vehicles are overrepresented in fires in Norwegian road tunnels. This is in line with international research. The third main finding is that the causes of road tunnel fires involving heavy and light vehicles are different. This is also in accordance with international research. The fourth important and unique finding of the study is that subsea road tunnels are overrepresented in the statistics of fires in Norwegian road tunnels.acceptedVersio
Risk and irreversibility of transport interventions
Get PDFInfrastructure decisions and transport policies are often based on the notion that all decisions are made at one single point in time, based on full information and an accurate evaluation of the benefits and costs of different alternatives. The reality is very much different, especially in the transport sector, due to the complex and dynamic nature of the transport system and the interplay between the many sub-systems that comprise it. Inherent in such complexities are elements of uncertainty, risk, irreversibility, path dependency and lock-in effects. This article reviews some of the existing literature on risk and risk management. It argues that one way of better accounting for the above elements associated with risk and uncertainty is to devote efforts at the planning stage to the identification of possible unintended adverse effects, as well as during and after implementation of policy measures or policy packages. While it is imperative to address potential unintended adverse effects ex-ante, it is equally important to monitor policy measure or packages ex-post to identify unintended effects and to evaluate whether the initial objectives are being met. Since circumstances are very likely to change over time and unintended effects can arise, there is a need for flexibility in the design of policy packages to allow as much as possible changes in the package if and when intentions and outcome do not match.acceptedVersio
ADHD and relative risk of accidents in road traffic: A meta-analysis
Get PDFThe present meta-analysis is based on 16 studies comprising 32 results. These studies provide sufficient data to estimate relative accident risks of drivers with ADHD. The overall estimate of relative risk for drivers with ADHD is 1.36 (95% CI: 1.18; 1.57) without control for exposure, 1.29 (1.12; 1.49) when correcting for publication bias, and 1.23 (1.04; 1.46) when controlling for exposure. A relative risk (RR) of 1.23 is exactly the same as found for drivers with cardiovascular diseases. The long-lasting assertion that “ADHD-drivers have an almost fourfold risk of accident compared to non-ADHD-drivers”, which originated from Barkley et al.’s study of 1993, is rebutted. That estimate was associated with comorbid Oppositional Defiant Disorder (ODD) and/or Conduct Disorder (CD), not with ADHD, but the assertion has incorrectly been maintained for two decades. The present study provides some support for the hypothesis that the relative accident risk of ADHD-drivers with comorbid ODD, CD and/or other conduct problems, is higher than that of ADHD-drivers without these comorbidities. The estimated RRs were 1.86 (1.27; 2.75) in a sample of ADHD-drivers in which a majority had comorbid ODD and/or CD compared to 1.31 (0.96; 1.81) in a sample of ADHD-drivers with no comorbidity. Given that ADHD-drivers most often seem to drive more than controls, and the fact that a majority of the present studies lack information about exposure, it seems more probable that the true RR is lower rather than higher than 1.23. Also the assertion that ADHD-drivers violate traffic laws more often than other drivers should be modified: ADHD-drivers do have more speeding violations, but no more drunk or reckless driving citations than drivers without ADHD. All accident studies included in the meta-analysis fail to acknowledge the distinction between deliberate violations and driving errors. The former are known to be associated with accidents, the latter are not. A hypothesis that ADHD-drivers speed more frequently than controls because it stimulates attention and reaction time is suggested.acceptedVersio
Capturing the least costly way of reducing pollution: A shadow price approach
Get PDFThe production analysis literature is increasingly concerned with estimating marginal abatement costs. Yet, most studies do not emphasize the ways in which pollutants may be reduced and their costs, which makes them unable to identify the least costly compliance strategy. This paper utilizes the materials balance principle to relate pollution to the employment of material inputs. A production model which allows input and output substitution, downscaling of operations, pollution control, and emission permits purchases as compliance strategies is proposed, and the implications of joint and non-joint pollution controls for the trade-off between pollutants and desirable outputs are considered. Marginal abatement costs, reflecting the least costly way of compliance, are derived by exploiting the duality between the directional distance function and the profit function.acceptedVersio