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Inom samverkansprogrammet Nästa generations resor och transporter, som Trafikanalys är huvudansvarig för, har man identifierat ett behov av att finna och utveckla nya lösningar för resvaneundersökningar (RVU:er). Bakgrunden till detta är bland annat sjunkande svarsfrekvenser med dagens metoder, vilket skulle kunna ge problem med representativiteten. Det anses som mycket angeläget att utveckla nya metoder för datainsamling för framtidens RVU:er, både på kort och lång sikt. Det övergripande syftet med projektet är att göra en demonstrationsstudie som visar hur två datainsamlingsmetoder som har utvecklats för att samla in resevaneundersökningsdata presterar i fält, samt hur de presterar jämfört med ”traditionell” RVU (postal enkät och/eller telefonintervjuer). Projektet syftar också till att få bättre förståelse för hur olika rekryteringsmetoder kan användas för att framtida RVU:er ska kunna bli mer kostnadseffektiva. De två insamlingsmetoder som testats är webbenkät med karta och mobilapp. Tre rekryteringsmetoder har använts och dessa är rekrytering via slumpmässigt urval, webbpanel och crowdsourcing.

The overall purpose of the project is to conduct a demonstration study that shows how two data collection methods that have been developed to collect travel survey data perform in the field, and how they perform compared with traditional TS (i.e., postal questionnaires and/or telephone interviews). The project is also intended to provide a better understanding of the ways in which different recruitment methods of respondents can be used so that future TS can be more cost effective. The two collection methods tested consist of a mobile app and an online questionnaire with a map to assist the respondents to identify travel destinations. Three recruitment methods were used, i.e., recruitment via random sampling, a web panel, and crowdsourcing. The portion of the random sample that received an online questionnaire was divided into two groups. Half the group was given no incentive, while the other half received a gift card worth SEK 100 after answering the questioner. Those who were recruited via a web panel and were to use the mobile app were rewarded in the form of a gift card worth SEK 100 if, at minimum, they made corrections to trips made on one day registered in the mobile app. A nonresponse analysis was performed of the random sample for both the online questionnaire and the mobile app. Cost estimates for each collection method and recruitment method were also performed, as were uncertainty estimates. Overall, the study shows that the mobile app registered significantly more trips per respondent than did the online questionnaire, while the distances travelled were comparable. There are several possible interpretations of this. One is that people who responded to the online questionnaire either forget about and/or combined short trips (particularly trips made for the purposes of leisure or shopping, and using the travel modes walking and car). One presumable explanation for this is that it is easier to confirm/correct the trips that the mobile app suggests than it is to recall and enter all trips in an online questionnaire. Another possible interpretation is that people responding to different data collection methods have different travel patterns. Yet another explanation is connected to technique issues regarding the different data collection methods.

Detta VTI notat presenterar en beräkningsmetod för beräkning av förväntad kölängd och restidsfördröjning för enfältiga vägavsnitt utan omkörningsmöjligheter. Metoden utvecklades 2001 och presenterades i ett PM. Bakgrunden till modellutvecklingen var att dåvarande Vägverket (nu Trafikverket) planerade att införa så kallade 1+1-vägar, det vill säga, vägar med längre delsträckor utan omkörningsmöjlighet. Den utvecklade beräkningsmetoden har sedermera visat sig värdefull även vid framkomlighetsberäkningar för 2+1-vägar med varierande andel tvåfältsavsnitt och har använts vid framtagning av hastighetsflödessamband till Trafikverkets ”Effektsamband för vägtransportsystemet”. Metoden använder avsnittslängd, trafikflöde samt medelhastighet och standardavvikelse som indata. Metoden är uppdelad på beräkning av effekter på grund av enstaka långsamtgående fordon samt effekter vid ”normal” hastighetsfördelning. Då mätdata saknades vid modellutvecklingen jämfördes metoden med simuleringskörningar med den mikroskopiska trafiksimuleringsmodellen AIMSUN. Resultaten visar på en relativt god korrelation men generellt så ger den analytiska metoden cirka 1,2 procent lägre restidsfördröjning. En stor del av skillnaden mellan modellerna vid måttliga flöden bör kunna härledas till det stokastiska inslaget i simuleringen. Det bör även påpekas att varken den analytiska modellen eller trafiksimuleringsmodellen har kalibrerats och validerats mot verkliga data för denna typ av väg. Skillnaden mellan modellerna innebär således inte att den analytiska modellen självklart är den som avviker från verkligheten. This VTI report presents a method for calculating expected queue length and travel time delay on one lane road sections without overtaking possibilities. The method was developed 2001 and presented in a working paper. The background for the model development was that the Swedish Road Administration (now the Swedish Transport Administration) planned to build so called 1+1 roads, i.e. roads with longer sections without overtaking possibilities. The method developed has later on also shown to be valuable for level of service calculations of 2+1 roads with varying share of two lane sections and for developing speed-flow relationships for the Administration’s ”Effect calculations for road facilities”. The method uses section length, traffic flow, average speed and standard deviation as input. The method is divided with respect to calculation of effects due to single slowrunning vehicles and effects at “normal” speed distribution. Since no data were available when the model was developed, the model results were instead compared to traffic simulations with the microscopic traffic simulation model AIMSUN. The results show a good correlation but the analytical model gives in general approximately 1.2 per cent lower travel time delay. The differences can probably partly be explained by the stochastic parts of the simulation model. One should also remember that neither the analytical model nor the simulation model has been calibrated and validated with real data for this type of roads. Thus, the differences between the models do not necessary imply that the analytical model is the one deviating from reality.

In studies of traffic safety is it important to have good knowledge of both internal and external factors. Examples of the former are driver behaviour and the roads’ safety standard, while examples of the latter are the demographic structure and the economic situation. This report includes a survey of methods used by previous researchers comprising which variables they used as indicators of the state of the market. It was concluded that unemployment was the most common economic variable, where an increase in unemployment indicates a decrease in the number of killed road users. The same result was found when a time series analysis was performed on Swedish data. It was also shown that part of the reduction in the number of fatalities in Sweden during a recession was explained by young drivers’ reducing their car use. There is, however, still a remaining effect of unemployment that cannot be explained by young drivers car use. One theory is that the state of the market affects the road users´ travel patterns. Data collected from fatal accident reports during the recession in December 2008-March 2009, were compared to the same period in 2005/2006, 2006/2007 and 2007/2008 during which period the economy was stronger. The only significant difference was that the number of fatalities and number of fatal accidents were higher during periods of economic growth. No significant difference was found with respect to, among others, accident type, time of day, age or gender distribution. VTI rapport R704A är en förkortad engelsk version av VTI rapport 704, ”Trafiksäkerhet och konjunktur: modellansatser och litteraturstudie” utgiven 2011

Det saknas idag tillfredsställande effektmodeller för beräkning av konsekvenser och kostnader för trafikanterna av olika underhållsstrategier. Det största problemet identifierat av Trafikverken/Vägverken i Finland, Sverige, Norge och Estland är sambandet mellan vägytans tillstånd och olyckor, effekten av den viktigaste tillståndsparametern spårdjup för trafikantkostnaderna, liksom betydelsen av trafikantkostnaderna/- effekterna för ett vägnät som är i ett huvudsakligen gott tillstånd. Detta är problem som måste lösas för att bättre kunna rättfärdiga budgettilldelningen för vägunderhåll. VTI har därför i uppdrag på finska Trafikverket och med finansiering även från de övriga Trafikverken/Vägverken, genomfört en studie för att avgöra hur spårdjup påverkar olycksrisken för trafikanter. Separata analyser har gjorts för data från Sverige, Finland respektive Norge. Det antogs att olycksrisken också beror på andra vägtillståndsvariabler, t.ex. längsgående ojämnhet, textur, tvärfall, geografiskt läge (land), fordonsflöde, klimat, väderförhållanden etc. En modellansats valdes som skulle kunna hantera påverkan av alla dessa övriga vägtillståndsvariabler, samt eventuella interaktioner mellan dessa, på olycksrisken. Det antogs vidare att förhållandet mellan olycksrisk och spårdjup inte nödvändigtvis är en linjär funktion, varför spårdjup delades upp i ett antal kategorier. Det beslutades också att separata ekvationer skulle härledas för olika hastighets- och ÅDT (Årsmedeldygnstrafiken)-klasser. Spårdjupskategorier samt hastighets- och ÅDT-klasser valdes för att matcha varje lands strategier för underhåll. Den övergripande slutsatsen av analysen är att data inte ger stöd för några allmänna regler i en underhållsplan. Det finns inga resultat från studien som säger att djupare spår generellt tenderar att öka olycksrisken. Det finns heller inga resultat som säger att spår har samma påverkan på olycksrisken i olika ÅDT-klasser vid en given hastighet eller vice versa. Det tycks finnas en ökad risk vid spårdjup ? ca 15 mm i högsta hastighetsklassen, men resultaten skiljer sig åt mellan olika ÅDT-klasser och inte är lika i angränsande hastighetsklasser, vilket gör resultaten svåra att förstå och mindre användbara för att ange regler för underhåll. För norska data erhölls inte samma resultat i den högsta hastighetsklassen (> =90 km/tim), denna skiljer sig dock från de svenska och finska högsta hastighetsklasserna (> =110 km/tim-vägar respektive motorväg) There are currently no satisfactory effect models for calculating the consequences and costs for road users of different maintenance strategies. The main problems identified by the Transport/Road Administrations in Finland, Sweden, Norway and Estonia, are the relationship between road surface condition and accidents, the effect of the most important state parameter rut depth on road user costs, as well as the role of road-user costs/effects of a road network that is mostly in good condition. These are problems that must be resolved in order to better justify budget allocation for road maintenance. VTI has therefore on commission by the Finnish Transport Administration and with funding from the other Transport/Road Administrations conducted a study to determine the influence of rut depth effects on the accident risk of road users. Separate analyses were made of data from Sweden, Finland and Norway, respectively. It was assumed that the accident risk also depends on other road condition variables, such as longitudinal unevenness, texture, cross slope, geographic location (country), vehicle flow, climate, weather, etc. A model approach was chosen that could address the impact of all these other road condition variables, and the possible interactions between them, on the accident risk. It was assumed that the relationship between accident risk and rut depth is not necessarily a linear function, why rut depth was divided into several categories. It was also agreed that separate equations should be derived for different speed and AADT (Annual average daily traffic) classes. Rut depth categories, as well as speed and AADT classes were chosen to match each country's strategies for maintenance. The overall conclusion of the analysis is that the data does not support any general rules for a maintenance scheme. There are no results to show that deeper ruts generally tend to increase the accident risk. Nor are there results that show that ruts have the same influence on the accident risk for different AADT classes at a given speed or vice versa. There seems to be at increased risk for ruts ? about 15 mm in the highest speed class, but the results differ between AADT classes and are not similar in adjacent speed classes, making the results difficult to understand and less useful to specify the rules for maintenance. For the Norwegian data this trend can not be seen in the highest speed class (> = 90 km/h), but then this speed class differs from the Swedish and Finnish highest speed classes (> = 110 km/h roads and motorways, respectively).

VTI har utvärderat sporthojskurserna som Sveriges MotorCyklister erbjuder. Utvärderingen har skettgenom två delstudier. I den första delstudien genomfördes telefonintervjuer med personer som deltog ikurserna år 2007. Syftet med den kvalitativa delstudien var att utröna vilken behållning deltagarna hadeav kurserna, vilka lärdomar som dragits och hur syftet har tolkats.Den andra delstudien omfattade en uppföljning av försäkringsrapporterade skador (person- och/elleregendomsskador) under perioden 2007–2009. Två grupper jämfördes: de som deltagit i en avanceradSMC-kurs och de som inte deltagit i någon sådan kurs.Ur intervjustudien framkom att kursernas upplägg fick övervägande positiva omdömen. Körning på vägskiljer sig från bankörning, vilket gör att alla moment inte blir aktuella vid de hastigheter och omständighetersom förekommer i trafiken. Några förbättringsförslag fördes fram som handlade om att få merindividuell återkoppling, att använda videokameror och att få ut skriftligt material före kursstarten.Utifrån uppföljningen av försäkringsrapporterade skador konstaterades att ingen signifikant skillnadförelåg mellan dem som genomgått kurs/kurser och dem som inte gått en avancerad kurs i SMC:s regi.Någon trafiksäkerhetseffekt av SMC:s sporthojskurser gick inte att påvisa med hjälp av det tillgängligadatamaterialet.Fördelar och nackdelar med olika angreppssätt för att undersöka vilken effekt fortbildning har på trafiksäkerhetdiskuteras. VTI has evaluated further training courses offered by the Swedish Motorcyclists Association (SMC) to riders of super-sport motorcycles. This was done through two substudies. In the first study, a series of telephone interviews were performed with persons who participated in the courses in 2007. The aim with this qualitative part of the study was to identify what respondents recalled from their participation in the courses, what they learned from them, and how the aims of the course have been interpreted. The second study included a follow-up of insurance reported claims during the period 2007-2009. Two groups were compared: those who participated in SMC further training course and those who did not participate in any such course. From the interview study, it was found that the course structure, i.e. practical exercises interleaved with discussions, received largely positive comments. Riding a motorcycle on public roads was seen as significantly different to riding on a designated track or course, which is why not all aspects of the further training course were viewed as relevant for speeds and circumstances that arise in normal traffic conditions. Some suggestions for improvement dealt with greater individual feedback, use of video cameras, and distribution of printed course material in advance. According to the follow-up study of insurance reported claims, no significant difference existed between those who completed the course/courses and those who have not passed SMC further training course. Any traffic safety effect of the SMC's courses for sport motorcycle riders was thus not possible to detect by the available data material.

En kunskapssammanställning avseende nyare metoder för att öka säkerheten vid vägarbetsplatser hartidigare genomförts. Den resulterade i en lista med åtgärdsförslag. Vägverket har prioriterat utvärderingav flera av de föreslagna åtgärderna. Utvärderingar avseende tre av dessa åtgärder redovisas i dennarapport. - Intelligent kövarningssystem, - Variabla meddelandeskyltar (VMS) vid intermittent vägarbete, - Optiska hastighetslinjer. De tre åtgärderna har testats i samband med verkliga vägarbeten och alla tre åtgärderna har var och en påsitt sätt visat sig ha potential att öka säkerheten vid vägarbeten. I rapporten pekas på frågor som återståratt besvara samt ges flera förslag på alternativa utformningar.De optiska hastighetslinjerna var den åtgärd som var klart billigast att implementera, men åtgärdenfungerar bara vid barmark. För att kunna utnyttja metoden med optisk synvilla även vintertid föreslås ettförsök med skärmar som placeras ut med succesivt minskade avstånd på sträcka där hastighetssänkningeftersträvas.Positiva reaktioner avseende de testade åtgärderna och deras effekter har erhållits både från vägarbetareoch driftledare. A state-of-the-art literature survey concerning the improvement of road-work safety has previously been carried out. A list of potential new measures was produced and several of these were prioritized, for further investigation, by the Swedish Road Administration. The investigations of three of these prioritized measures are documented in this report: - Intelligent congestion warning system, - Dynamic message sign (DMS), - Optical speed bars. The measures were tested in field at real road-works and all three measures, each in their own way, have the potential to increase traffic safety at road-work zones. In the report, questions that remain to be answered are highlighted and some alternative designs of the measures are proposed.

Buses in Sweden have a low accident risk. However, statistics from 1996 - 2002 indicate that the number of bus accidents in Sweden with personal injuries have been increasing by 4% yearly. Buses also have a higher percentage of accidents that occur on ice/snow covered roads than other vehicles. In Sweden passenger cars must be equipped with winter tyres during the winter period. There is no such regulation for heavy vehicles, and many buses are using summer tyres all around the year. The present project had the purpose of looking at the bus-winter problem in more detail, with the main focus on tyres. Four different studies were carried out: tyre tests, focus group discussions, driving simulator tests and an accident study. Here is given a short summary concerning methods and conclusions of each sub project. Tyre tests on smooth ice did not show any significant difference between summer tyres and non-studded winter tyres, while studded tyres exhibits a better ice grip than non-studded tyres. Nor did driving simulator tests with driving on ice covered road under the influence of heavy wind from the side show a difference between summer tyres and non-studded winter tyres. Also in these tests studded tyres were superior to non-studded. Accident statistics indicate that buses with summer tyres on the steering axle and winter tyres on the drive axle have the lowest estimated accident risk, which is in accordance with the results in a previous study. The results are however not statistically significant due the low number of accidents. Three focus groups were carried out and the importance of the tyres for traffic safety during winter was discussed. It is however hard from the gathered discussion material to estimate just how important the tyres really are. The results do not warrant a winter tyre regulation for heavy vehicles, and a restriction of the use of studded tyres for buses would probably have negative consequences on traffic safety.

Rapporten sammanställer behov av och tillvägagångssätt vid skattning av gång- respektive cykeltrafikensandel av resandet och innefattar en analys av befintligt dataunderlag i form av resvaneundersökningaroch flödesmätningar. I analysen jämförs olika metoder och betydelsen av skillnader mellan metoderna,för uppföljning av resandet med gång och cykel, diskuteras. Både metoden i sig med dess definitioneroch avgränsningar liksom dess kvalitet i genomförandets olika faser spelar roll. Detta får konsekvenservid jämförelse mellan olika platser, men även för uppföljning över tid.De flesta kommuner har någon typ av mål vad gäller cykeltrafiken medan målformuleringar för gångtrafikenär mer sällsynta. Att öka cyklandets andel av det totala resandet, är den vanligast förekommandemålformuleringen. Andelsmålet följs emellertid sällan upp, utan istället mäts oftast antalet cyklister ivissa punkter. Resvaneundersökningar och flödesmätningar mäter olika saker och kan leda till olikaslutsatser. Mätningarna kan visa att det cyklas som aldrig förr, medan resvaneundersökningar visar attcykelandelen minskar. Båda slutsatserna kan vara riktiga och speglar betydelsen av metoderna, men ävenav måtten (antal eller andel). Andelsmått beror av fler komponenter än gång- och cykeltrafiken i sig,framför allt det totala resandet. Därför är inte bara andelar intressant utan även andra mått, somexempelvis antal resor per person. This report summarises the needs for, and the procedures applied in, estimating the share of total travel represented by pedestrian and cycle traffic, and comprises an analysis of existing data in the form of travel surveys and flow measurements. Different methods are compared, and the significance of the differences between the methods for monitoring pedestrian and cycle travel is discussed. Both the method as such with its definitions and limitations, and the quality of the various phases in its implementation, play a part. This has consequences in comparisons between different places and also for monitoring over time. Most local authorities have some type of target with regard to cycle traffic, while target formulations for pedestrian traffic are less frequent. To increase the cycling share of total travel is the most common target, however, seldom followed up, and the numbers of cyclists at certain points are measured instead. Travel surveys and traffic flow measurements measure different things, and may draw different conclusions. The measurements may show that people cycle more than ever before, while travel surveys show that the cycling share is decreasing. Both conclusions may be right, and they reflect the importance of the methods employed, and also of the units. The unit "share" is made up of more components than pedestrian and cycle traffic as such, and depends above all on the total travel. It is therefore not only the proportions that are of interest but, for example, also the number of journeys per person.

The benefit being studied in this socio-economic evaluation pertains to the decrease achieved in the number of traffic accidents involving drunk drivers. Roughly 2% of those who are charged with drunk driving will be involved in a traffic accident while drunk within 10 years after being found guilty of drunk driving. This figure could be reduced were it possible to successfully reduce drug and alcohol use by these perpetrators after they have been found guilty. Acceptance of the offer made under the Skellefte Model is presumed to have such an effect. The effect of the Skellefte Model differs from individual to individual. It is assumed that the Skellefte Model will influence an individual charged with drunk driving to refrain for longer periods from driving while drunk. This would in turn decrease the likelihood of the individual being involved in an accident while drunk from 2% to some lower level, which would be determined by how much longer such periods last, which would in turn entail fewer drug- or alcohol-related accidents. Two scenarios have been studied; one in which the median increase in the length of time without a recurrence of drunk driving equals one week, and another where the median period is one month. A decrease in accidents represents a social benefit. This benefit must be weighed against the costs in the form of person-hours expended in extending the offer to suspected drunk drivers and arranging an interview. These costs have been estimated based on the questionnaire responses. The calculations indicate that if the effect is that the median increase in time without driving drunk equals one week, then each interviewed suspected drunk driver represents a socio-economic loss of roughly SEK 6, while a median time of one month yields a gain of nearly SEK 82. If the median increase in time without drunk driving is one month, a socio-economic gain is achieved, although no fixed costs have been factored into the analysis. The magnitude of the fixed costs ultimately associated with the Skellefte Model is unclear. Two scenarios have been studied, one corresponding to one full-time worker (taking into account earnings for one year and all overheads), another corresponding to two such workers. To cover these costs, a given number of suspected drunk drivers must be questioned annually in accordance with the Skellefte Model. Two scenarios have been studied, with the offer made to 12,000 people and 24,000 people, respectively. Socio-economic calculations have been performed for each combination of scenarios. We find that the socio-economic benefit is positive both when the median increase in time without a recurrence of drunk driving equals at least one month and for the alternatives in which 24,000 suspected drunk drivers are questioned annually or the fixed costs correspond to one full-time worker.

The views of car drivers concerning antilock brakes (ABS) and electronic stability control (ESC) systems, and their experience of these, have been studied. A study has also been made of their intentions to behave in a certain way in three critical driving situations. The investigation was performed as a questionnaire survey sent by post to 1 000 car drivers with an electronic stability control system and to 1 000 drivers of similar cars without an electronic stability control system. The investigation was carried out in the autumn of 2008. A total of 959 questionnaires were answered, i.e. a response rate of 48%. The results show that about 90% of the car drivers with an electronic stability control system know that the car is equipped with the system. If the car drivers without an electronic stability control system in the car are studied, more than 35% erroneously state that the car has the system. Almost all drivers (over 95%) are aware that they have antilock brakes. In the above risk situations, the drivers consistently state that they are more likely to take a risk when they think they have the support system, than when they do not have one. The increased tendency to take risks is approximately the same for all the three situations. The results show that men are more riskprone than women. As regards the age, there is a consistent pattern that the youngest age group is always represented in the age group or age groups which have the highest tendency to take risks. It is also shown that when "Theory of planned behaviour" is used, the intentions of between 41-70% of the drivers are explained by the model.

The Skellefte Model is a project whose purpose is to reduce the number of repeated drunk driving offences by improving cooperation between the police, social services, addiction treatment systems, county administrative boards, public prosecutors, judges and the criminal justice system. The project's key concept is that suspected drunk drivers must come into contact with municipal social services or be taken care of by the county council addiction treatment system as quickly as possible, and preferably within 24 hours after being apprehended and questioned by the police. The evaluation indicates that the Skellefte Model is socio-economically beneficial. A majority of those who are working in the project also believe that the model works well, but that there are numerous problems, such as administrative problems and routines, a need to better embed the model among administrators, etc. The evaluation also shows that there is room for improvement in the handling of drugged drivers. The results differ greatly from county to county. The inter-county differences are likely due to factors such as when the project began and discrepancies in terms of the application of routines, motivation and embedment among employees. They may also be attributable to some extent to the fact that some aspects of the Skellefte Model are being applied in different ways and adapted to disparate local and regional conditions.

Roadworks are signposted to make road users realise that roadworks are in progress, advise them how they must act and how they can pass the roadworks in a safe manner. In spite of this, incidents and accidents do occur at roadworks where road users are involved. It is important to chart the problems which arise when those working on the road and other road users come into contact. A part of the work is to study the road accidents and incidents that occur at roadworks. To be able to do this, there is a need for relevant statistics concerning such accidents and incidents. Since conditions at roadworks are special, it may be necessary to compile special statistics concerning the road accidents and incidents that occur in connection to these. The aim is to compile statistics concerning incidents at roadworks. These statistics must provide a description of where, when and how the incidents occur. They must also serve as a model for the way in which regular collection of data concerning road accidents and incidents at roadworks can be carried out. Vägverket Produktion, the Production Section of the Swedish Road Administration, collects and compiles reports on incidents and accidents which occur in conjunction with their work on roads. This study comprises about 150 such incidents and accidents collected from 2004 until autumn of 2007. The method employed was to set up, with the support of the descriptions of occurrences, new variables for the compilation of statistics. These variables can then, presumably after a lot of modifications, be used in a more regular reporting of incidents in which all those who perform work on roads take part.

VTI has carried out acceptance testing of companies that would like to do road surface monitoring in Finland. This has been done on commission of the Finnish Road Administration. This kind of acceptance testing has been done in Sweden by VTI in cooperation with the Swedish Road Administration several times (four times). With the experience of the tests in Sweden a test method adjusted for the Finnish needs have been composed. The purpose of the method is to accept or reject the participating companies for doing either object or network measurements or both. This is done by checking the validity and repeatability for the object part and the reproducibility for the network part. The tests for the object part involve measurements at test sections including measuring with reference methods as well as repeated measurements on a route. For the reproducibility test, done at the network measuring acceptance, runs with different combinations of vehicles and drivers/operators are carried out. The tests give answers to questions like: - The technical skill to measure according to the procurement specifications. - The ability and type of organisation to take care of and process data under given circumstances like this test. - The ability to deliver data of right quality in time. To be accepted as a contractor of network level measurements the company also has to be accepted for object measurements.

In June 2006, the Swedish Road Administration was mandated by the Government to improve the description of the health effects of road traffic accidents. Under the terms of this mandate, a proposal was to be made as to how the recording of alcohol and drug related accidents can be improved, and how sample surveys of the prevalence of drivers under the influence of alcohol and/or drugs should be performed. This note describes the data used for these parts of the mandate. One common condition for both these parts is that possible screening methods for drivers under the influence of narcotics should be studied. In order to measure the proportion of traffic mileage travelled by drink/drug drivers, the investigation should be organised as a statistical sample survey where the police check drivers at sites selected at random. As regards selection in time, it may be reasonable to use quota sampling. In the present situation, we do not consider that it is possible to carry out regular surveys of drug driving. If the regulations are amended so that routine controls can be performed, and if the police begin to use screening instruments for drug tests, regular surveys can be performed. These surveys can then be integrated with the investigations regarding alcohol, by requiring the stopped drivers to give samples for both alcohol and for drugs.

This study has been performed by VTI by commission of the Road Traffic Inspectorate in Sweden. The objective has been to scrutinise, discuss, compile and comment on measures, changes in conditions and effects concerning both the road, the vehicle and the road user. One further objective has been to relate, as far as possible, the effects/changes to the actual development of fatalities in traffic, in the first place over the period 1996-2006. It is found that for many factors, the conditions, measures and associated effects are insufficiently known. This is especially true for changes over time. This is unsatisfactory since, at the same time, there is strong evidence that these factors have, or may have, a considerable impact and that it is a high proportion of all traffic fatalities which are affected - either positively or negatively. We do not know about changes in conditions regarding speeds, person km travelled by age and gender, alcohol in traffic, use of mobile telephones when driving, and attitudes and deliberate traffic violations. There are no data for changes concerning risk for car drivers of different ages and genders. Effects concerning fatalities are insufficiently known for changes in traffic mileage (all other factors being constant), changes in economic conditions (effects apart from impact on traffic mileage), automatic traffic safety control speed cameras, certain physical measures, the aggregate effect of more recent vehicles, measures to influence alcohol in traffic, and attitude modification. There are no data for simultaneous analysis of accidents/injuries/fatalities, as well as for exposure, speed, road, vehicle and road user.

In today's vehicles, active safety systems are introduced addressing a large variety of safety issues such as providing optimal stability control, braking effect, preventing spin and rollover, as well as collision avoidance, to mention just a few. In this study a literature review was performed in order to establish how the traffic safety performances of active safety systems with focus on Antilock Braking System (ABS) and Electronic Stability Control (ESC) are assessed. The areas covered were statistical evaluation, testing and driver behaviour. The literature review showed that in particular statistical methods, based on odds ratios, had been used in order to evaluate the traffic safety effect. In order to evaluate the effect of ESC in physical testing there are several test methods described in this report. Estimations of driver behaviour effects have been carried out by surveys among vehicle owners. Experiments performed in field or in simulator have also been found in the literature. From EU projects a variety of measures and test methods are available for assessment of driver behavioural effects.

The aim of this report is to make an initial survey of disruptions to rail traffic in winter. This survey is used in studying the prospects for submitting a project application to Banverket, the authority responsible for rail traffic in Sweden. The total cost of the effects or consequences that affect rail traffic because of the winter climate can be broken down into several items. First and foremost, there are the direct costs of Banverket for winter maintenance and the direct costs of the train operators. To this must be added the indirect costs incurred by passengers and freight customers. The size of these indirect costs in a socio-economic perspective depends on the extent of the delays and the way the delays are valued in monetary terms by passengers and freight customers. We have scrutinised the approach and the model structure for the road sector that are set out in the Winter Model. This model will soon be used on the national road network to describe the most important socio-economic effects of various strategies and measures in winter road management. With this as the starting point, a first draft for an effect model for the winter management of rail infrastructure has been drawn up. We believe that this effect model will be found valuable for structuring and analysing the impact of winter on the various elements of rail infrastructure.

The purpose of this study is to show the potential of improved traffic safety from compulsory alco-lock for those convicted for drink-driving. About 800 of all drivers yearly involved in police reported road accidents with casualties in Sweden are suspected for driving under the influence of alcohol or other drugs. However, many of those drivers have never been convicted for drink-driving, many drivers drive without driving license and many drivers drive cars that are borrowed or stolen. Therefore it is vital to quantify the proportion of the 800 drivers involved in accidents that might be using an alco-lock if that would be compulsory for drivers convicted for drink-driving. One way to assess the potential of improved traffic safety of compulsory alco-lock is to assume that it is drivers with valid or cancelled driving licenses that are affected. The mean number of drivers involved in police reported road accidents with casualties, where the driver has a valid or cancelled driving license and is suspected of drunk driving, is 626 per year, with a 95 percent confidence interval ranging between 605 and 649 drivers. 17 percent of those drivers where convicted for drink-driving at least once during the 10 years preceding the accident and the 95 percent confidence interval is ranging between 16 and 19 percent. A regulation of compulsory alco-locks for drivers convicted of drink-driving is estimated to reduce the number police-reported road accidents with casualties with with 571 during the first ten years, of which 218 are accidents with fatalities or serious personal injuries.

In the Road Condition Model one wants to be able to predict the transition between different winter road conditions. One such example is the transition from loose snow all across the driving lane to loose snow except in wheel tracks, where the condition is changed to ice or bare road. Each vehicle passing as long as there is loose snow across the whole driving lane will remove a certain amount of loose snow from the developing wheel tracks. The amount of removed loose snow is assumed to vary between different types of vehicles. The Road Weather Information System, RWIS, delivers information on the amount of loose snow falling on the road. The traffic flow is measured by inductive loops. The amount of loose snow in wheel tracks is measured intermittent. Then one has information of traffic flow and the amount of removed loose snow from wheel tracks (determined as the difference between the amount af loose snow falling on the road and the amount remaining in the wheel tracks). Trough regression analysis one can determine the statistical relation between traffic flow and amount of removed loose snow. However, one problem is that on some occasions there is no loose snow at all remaining in the wheel tracks at the time of observation. In that case one can assume that the observed amount of traffic flow would have removed more snow if the snow fall would have been heavier. Those observations are considered censurered since the actual amount of removed loose snow exceeds the observed.

The purpose is to test the hypothesis that the choice of strategy for preventive maintenance of rail infrastructure might affect the amount of serious disruptions in the train traffic. The relation between preventive maintenance and serious train traffic disruptions can be divided into two parts. On one hand it is the relation between the chosen strategy for preventive maintenance and the state of the rail infrastructure. On the other hand it is the relation between the state of the rail infrastructure and the amount of occurring train traffic disruptions. Either the sub relations can be analysed and quantified separately or one might try to perform an analysis without dividing the relation between preventive maintenance and serious train traffic disruptions into two parts. An operational definition of serious disruption in train traffic in this context is that faults or damages on the rail infrastructure cause such severe delays that the planned turnover of train vehicles cannot be maintained, cancelled train traffic or the closure of a railway. Several methods for quantifying serious train traffic disruptions, based on available train traffic data, are suggested. It is clear from these methods that faults or damages on the overhead contact line dominate increasingly as higher weight is put on the larger train delays, while the opposite applies to faults and damages on signal system. The result of a Delphi study is presented, where two scenarios are tested. The purpose of the study is to let experts on maintenance of rail infrastructure judge to what extent the decision of preventive maintenance strategy may affect the amount of occurring train traffic disruptions. The first scenario means that the necessary maintenance strategy in order two reach the target standard for the rail infrastructure is implemented. In the second scenario a maintenance strategy is implemented that is 50 percent more ambitious than the strategy of the first scenario.

In an earlier VTI study from 1997 in which the tyre usage for heavy vehicles was surveyed, statistics suggested that buses may have a larger problem with slippery roads compared to other vehicle types, like personal cars and heavy trucks. The statistical data was however not large enough to conclude that this is the case. Therefore, the present study was conducted with the aid of accident data for various vehicle types collected from VITS, the information system for traffic safety of the Swedish Road Administration. The information concerns accidents that occurred during seven winters 1995/1996-2001/2002. Corresponding information has also been collected from Finnish accident data. All of the statistical analyses in this study indicate problems with traffic safety for buses on icy or snowy roads. However, none of these results are statistically significant. The statistical uncertainty in these results stems from a low number of accidents, but also from a lack of information regarding the actual travelled distance on different road conditions for the vehicles. It is probably necessary to know the travelled distance on different road conditions for buses to make a conclusion about accident probability for buses on winter roads. We will therefore make inquiries to bus companies in Sweden during the winters 2005/2006 and 2006/2007 concerning the travelled distances on different road conditions to complete the present study.