Emergency driving entails challenges, one being the interaction with other road users. Drivers’ attitudes towards Emergency vehicles (EVs) may affect their willingness to move over. Previous research has suggested that attitudes towards the different emergency response organizations may differ, but no previous research has compared the driver behavior aspects associated with the two organizations. The purpose of the present study was to examine drivers’ attitudes and driving behavior around approaching ambulances and police vehicles. A total of 110 drivers participated in a driving simulator study where they were approached by emergency vehicles three times. After the drive, they were asked about their typical driving behavior and attitudes towards ambulance and police. No difference in driving behavior when interacting with either an ambulance or police vehicle was seen in the simulator data. There was a difference in expressed attitude towards the organizations. Drivers reported that they felt a higher level of stress, and were more aware of their driving when approached by a police vehicle compared to when approached by an ambulance. The participants stated that it is important to move over regardless of EV type.  

Effects of rear-light usage by daylight were examined. A field experiment measured passing vehicles’ lateral distance to a stationary car, as an effect of rear-light status. A questionnaire survey measured car drivers’ perceptions regarding safety and visibility depending on rear-light usage, and their experiences, preferences, and beliefs about own usage of rear lights in daylight. An observational study measured percentages of cars with lit and unlit rear lights, respectively, in sunshine during summer. Results show that rear lights give greater lateral distance when being passed by. A car with lit rear lights is interpreted as more likely to start driving. Lit rear lights are preferred and estimated to give better visibility and traffic safety. Only a small proportion of drivers know that they drive with unlit rear lights in daylight, whilst the majority actually drive with unlit rear lights. Conclusion: lit rear lights in daylight improves traffic safety. It is therefore recommended that rear lights with sufficient brightness to be seen even in sunshine should be legally required.

This study investigates drivers’ eye gaze behavior in response to Emergency Vehicle Approaching (EVA) warnings. EVA warnings, delivered through in-car alerts, provide advance notice of approaching EVs, enabling drivers to move over in time. Previous research indicates that EVA warnings influence driver behavior positively, promoting safer interactions. This study expands further by exploring the role of system introduction to make drivers benefit from EVA warnings. 

A simulator experiment with 73 participants was conducted. Before driving, half of the participants were introduced to the EVA system. The participants were driving on a highway and were overtaken by EVs twice during a 20-minute drive. During the drive, half of participants received EVA warnings. Gaze distribution was analyzed in three areas of interest (Forward, Mirrors, Dashboards). Analysis of driving simulator data did not reveal any differences in driving behaviors. However, the analysis of drivers’ gaze distribution suggests that EVA warnings contribute to increased mirror usage, indicating early scanning for approaching EVs. Furthermore, drivers who were introduced to the EVA system before driving but never received an EVA warning in the simulator looked through the front windshield less than drivers who were introduced and received an EVA warning. 

This study contributes to understanding the driver gaze behavior when receiving an in-car warning for emergency vehicles and supports previous findings regarding EVA warnings positive impact of driver behavior.

Emergency vehicle lightings (EVL) mitigate the risk of collision and make drivers move over. The present paper explored how new alternative EVL designs can improve driver behavior in different emergency vehicle interaction scenarios. From workshops with 14 emergency responders, three scenarios (Emergency driving, Police pull-over, Emergency vehicle alongside the road) and 19 EVL blink patterns were chosen. These alternative EVLs were presented in an online survey with 2627 Swedish respondents. Alternative EVL affected reported driving behavior. Drivers reported being most certain of what is expected from them in the emergency-driving scenario. It is important to ensure that the EVL is easy to interpret in more unfamiliar emergency-vehicle interactions such as police pull-over. Only a third of drivers had seen the pull-over EVL currently used in Sweden. The current pull-over EVL in combination with a stop sign increased the chance of drivers reporting that they would pull over. 

A novel interface to provide robust, intuitive, and timely alerts to road users to move over for emergency vehicles (EVs) was tested in a seven-minute driving-simulator experiment. The interface, Augmented Emergency Lighting (AEL), mimics emergency lighting on emergency vehicles (i.e., flashing blue light), by using the cars’ interior lighting. AEL was initiated 30 seconds before an EV caught up and increased its brightness proportionally to the distance to the EV. The AEL alert was after 16 seconds accompanied by an Emergency Vehicle Approaching (EVA) alert, presented as a voice command and a text message on the dashboard. Comparisons were made between AEL+EVA alerts, EVA-only alerts, and no alerts, between groups (N = 61). Both AEL+EVA alerts and AEL-only alerts were highly successful in getting drivers to move over by slowing down and pulling off to the side as compared to when there were no alerts, but no significant difference between AEL+EVA and EVA-only was found. Questionnaire responses showed that AEL+EVA alerts were generally appreciated and that their timing was good. Further studies on learning effects and usability are discussed.

The purpose of the EVA pilot is to provide drivers with quick and accurate information and warnings about some of the possible hazardous events on the roads. This, in turn, can help prevent incidents and accidents, as well as reduce congestion. The EVA service is planned to cover Swedish highways and national roads and the pilot is aiming for deployment after the NordicWay 3 project. Furthermore, driving simulators will be used to gain a greater understanding of driver behavior when receiving EVA or Accident Zone Warnings. The pilot focuses on scenarios where the positive effects on traffic safety and emergency response times of reaching out with those warning messages are likely to be high. The established data flow infrastructure and software components from NordicWay 2 will be used.

Driving an emergency vehicle can be difficult. The driver of the emergency vehicle must navigate, communicate with emergency services, often drive at high speeds, and take surrounding traffic into account. Civilian drivers are required by law to give way to emergency vehicles with lights and sirens activated. Despite this, they sometimes fail to move over. One reason is not noticing the emergency vehicle in time.   

This dissertation aims to understand how technology can support civilian drivers in their interactions with emergency vehicles. One form of technology used to make drivers move over is emergency vehicle lighting. The results of this dissertation show that alternative designs of emergency vehicle lighting can affect driver behavior and that the current designs are not always suited to promote the most desirable driver behavior.   

Another technological approach to supporting drivers in their interactions with emergency vehicles is the use of Cooperative Intelligent Transport Systems (C-ITS). One C-ITS service is the Emergency Vehicle Approaching (EVA) warning. An EVA warning is an early in-car warning sent out to the driver before being overtaken by an emergency vehicle, providing more time to move over. Three driving simulator studies with EVA warnings were conducted in this dissertation. The results indicate that EVA warnings make drivers move over more quickly and thereby decrease delay time for emergency vehicles. Furthermore, there is a learning effect when receiving multiple EVA warnings, implying that drivers move over more quickly once they are familiar with the system. One of the simulator studies used eye tracking and showed that EVA warnings make drivers scan mirrors earlier, compared to when not receiving an EVA warning.   

Att framföra ett utryckningsfordon är utmanande. Utryckningsföraren förväntas navigera, kommunicera med larmcentralen, framföra utryckningsfordonet i inte sällan höga hastigheter och samtidigt ta hänsyn till omgivande trafik. Bilister är enligt lag tvungna att lämna fri väg för utryckningsfordon med blåljus och sirener. Trots det misslyckas ibland förare med att lämna fri väg. En anledning är att de inte hinner uppfatta utryckningsfordonet i tid.

Syftet med denna avhandling är att förstå hur teknik kan stödja förare vid interaktioner med utryckningsfordon. En form av teknik som används för att få förare att lämna fri väg är blåljus. Resultaten av denna avhandling visar att alternativa designlösningar för blåljus kan påverka förarnas beteende och att de nu-varande utformningarna inte alltid är optimala för att främja det mest önskvärda förarbeteendet.   

En annan metod för att stötta förare i deras interaktion med utryckningsfordon är uppkopplad fordonsteknik, så kallat Cooperative Intelligent Transport Systems (C-ITS). En typ av C-ITS-tjänst är Emergency Vehicle Approaching (EVA)-varningar. En EVA-varning är en tidig varning som skickas ut till bilisten innan utryckningsfordonet kör ikapp, vilket ger föraren mer tid att lämna fri väg. Tre förarsimulatorstudier med EVA-varningar genomfördes inom ramen för avhandlingen. Resultaten visar på att EVA-varningar kan få förare att lämna fri väg snabbare och därmed minska förseningar för utryckningsfordon. Dessutom finns det en inlärningseffekt med EVA varningar som innebär att förare lämnar fri väg snabbare när de är bekanta med EVA systemet. I en av simulatorstudierna användes ögonrörelsemätning som visade att EVA-varningar får förare att skanna av speglarna i bilen tidigare, jämfört med när de inte får någon EVA-varning.   

The interaction between emergency vehicle drivers and surrounding road users is associated with risks. This study explored the application of geofencing to improve interactions between drivers and emergency vehicles to reduce the risk of collisions in high-risk scenarios. Two high-risk scenarios, an off-ramp collision, and an intersection scenario, were used in two driving simulator experiments with 64 participants in total. Half of the drivers received a geofence-based warning about the upcoming traffic situation. The results indicate that geofencing, when applied to provide warnings in specific locations, improves driver behavior. In the off-ramp experiment, all drivers who received a warning avoided the off-ramp and thereby avoided the collision site, whereas all other drivers took the off-ramp. In the intersection experiment, the warning led to earlier deceleration, allowing the emergency vehicle to pass safely and with minimal delay; whereas nearly half of those who did not get a warning failed to yield to the emergency vehicle. The drivers acted based on the warning they received, even when they had not yet seen the emergency vehicle. The findings suggest that geofencing can improve driver behavior by detecting emergency vehicles early and reliably, thereby improving traffic safety and minimizing delay for emergency vehicles on call. 

Emergency driving is a demanding task. The ITS service Emergency Vehicle Approaching provides drivers with an in-car warning that an emergency vehicle is approaching. To ensure that the warning is efficient and reliable it must have a suitable timing. The EVA warning must be presented early enough to allow the driver to make a safe move-over maneuver. However, the distribution of EVA warnings is based on the most probable path of the emergency vehicle. If an EVA warning is distributed too early, it increases the risk of false alarms. In addition, if a warning is given too early the driver might deem it as irrelevant. Previous studies have distributed EVA warnings based on the distance between the emergency vehicle and surrounding cars. However, if the speed of the vehicle is not accounted for there is a risk of insufficient time for the driver to prepare for the emergency vehicle interaction. To explore suitable EVA timing, post-survey data from five driving simulator studies where drivers were exposed to EVA warnings were analyzed. The results suggest that 15-20 seconds could be an appropriate EVA timing. However, the required time for a move-over maneuver depends on the complexity of the current traffic situation.

Trots att en stor andel av svenska bilförare använder digitalt navigationsstöd finns lite kunskap om när, var, hur och hur mycket navigationstjänster används. Syftet med den här förstudien var att undersöka hur svenska bilister använder sig av navigationstjänster. För att skapa en första bild av förares användning av navigationstjänster genomfördes separata intervjuer med en lastbilschaufför, en brandman och en privatbilist. Resultaten av intervjuerna visar att förarna i väldigt hög utsträckning använder navigationstjänster. En enkät gick också ut till svenska bilförare via sociala medier. Totalt 1 890 enkätsvar kom in. Resultaten från enkätstudien visar att en stor majoritet av bilförare har erfarenhet av att använda navigationstjänster. Vanligast är att man använder en navigationsapp i sin mobiltelefon. Navigationstjänster används främst på okända vägar där man inte har så god lokalkännedom, vid längre resor och på sällanresor. Tilliten till information om plötsligt uppkomna hinder och trafikrisker (t.ex. trafikolyckor) via navigationstjänsten är låg, väsentligt lägre än den information som finns via polisman, digitala vägskyltar och radiosändning. Bilförarna uppgav att de anser att information om omledning av trafik samt avstängd väg är viktigast. Den trafikinformation som bilisterna tycker är viktigast (omledning av trafik, avstängd väg), samt det som flest nås av (trafikkameror, vägarbete) bör prioriteras vid Trafikverkets tillhandahållande av trafikinformation.

Although a large proportion of Swedish car drivers use digital navigation services, little is known about when, where, how, and how much these navigation services are used. The purpose of this pre-study was to investigate how Swedish drivers use navigation services. To create a first picture of drivers’ use of navigation services, separate interviews were conducted with a truck driver, a firefighter, and a civilian driver. The results of the interviews show that the drivers use navigation services to a very high extent. A survey was also distributed to Swedish drivers via social media. A total of 1,890 responses were received. The results from the survey show that a large majority of drivers have experience using navigation services. The most common is the use of a navigation app in a mobile phone. Navigation services are mainly used on unfamiliar roads with little local knowledge, on longer journeys, and on infrequent trips. Confidence in the information on sudden obstacles and traffic risks (e.g. road accidents) provided by the navigation service is low, significantly lower than the information provided by a police officer, digital road signs and radio broadcasting. The drivers stated that they consider information on traffic diversion and road closures to be most important. The traffic information that motorists think is most important (traffic diversion, road closures), as well as what most people are reached by (traffic cameras, roadworks) should be prioritized in the Swedish Transport Administration's provision of traffic information.