Alcohol-impaired driving continues to exact a significant toll among road users both in the United States and around the world. In 2017, in the U.S. alone, alcohol-impaired motor vehicle fatalities totaled almost 11,000 – a number that has seen very little change since 2009. To better address this ongoing problem, in 2008 the National Highway Traffic Safety Administration (NHTSA) and the Automotive Coalition for Traffic Safety (ACTS) formed a cooperative research partnership to explore the feasibility, the potential benefits of, and the public policy challenges associated with the widespread use of non-invasive technology to prevent alcohol-impaired driving. This partnership, known as the Driver Alcohol Detection System for Safety (DADSS) Program has made great strides forward in the development of in-vehicle technologies that will measure blood or breath alcohol and prevent alcohol-impaired drivers from driving their vehicles. Exploratory research in Phases I and II established the feasibility of two sensor approaches, breath- and touch-based, for in- vehicle use. In Phase III, the sensors have become increasingly refined, in terms of both hardware and software, as the program strives to meet the very high standards required for unobtrusive and reliable alcohol measurement. Numerous parallel research programs are currently underway including sensor development, development of calibration processes, materials and instrumentation that will verify the technologies are meeting these elevated standards, human subject testing in conditions that replicate those likely to be experienced in the real world, and real-world pilot field operational trials in diverse settings. At the completion of this effort a determination will be made as to whether the DADSS technologies can ultimately be commercialized. This paper will outline the technological approaches and the status of the various DADSS research programs.

The National Highway Traffic Safety Administration (NHTSA) and the Automotive Coalition for Traffic Safety (ACTS) began research in February 2008 to try to find potential in–vehicle approaches to the problem of alcohol-impaired driving. Members of ACTS comprise motor vehicle manufacturers representing approximately 99 percent of light vehicle sales in the U.S. This cooperative research partnership, known as the Driver Alcohol Detection System for Safety (DADSS) Program, is exploring the feasibility, the potential benefits, and the public policy challenges of more widespread use of non-invasive technology to prevent alcohol-impaired driving. The 2008 Cooperative Agreement between NHTSA and ACTS (2008 Cooperative Agreement) for Phases I and II outlined a program of research to assess the state of detection technologies that are capable of measuring blood alcohol concentration (BAC) or breath alcohol concentration (BrAC) and to support the creation and testing of prototypes and subsequent hardware that could be installed in vehicles.

The Driver Alcohol Detection System for Safety Program – a joint effort between the National Highway Traffic Safety Administration and the Automotive Coalition for Traffic Safety since 2008 – has been developing unique, in-vehicle breath-and touch-based alcohol detection systems to address the problem of alcohol-impaired driving. The sensors under development are intended to be passive, seamless with the driving task, non-intrusive, accurate, fast, reliable, durable, and requiring little or no maintenance. When installed in vehicles, the technology is intended to prevent alcohol-impaired driving when the driver’s blood alcohol concentration is at or above 0.08 %. Sensor technology, now in Phase III of development, is undergoing more extensive testing in real-world driving environments. Research vehicles are being fitted with breath-based alcohol sensors and comprehensive Data Acquisition Systems (touch-based sensors will be integrated once they have completed the requisite test protocols). Pilot Field Operational Trials have recently begun, and data are being collected. In this paper, an overview is provided of the instrumentation and integration of the test vehicles in readiness for field trials. Data is being collected from the DADSS alcohol sensors as well as from breath-alcohol reference sensors. Instrumentation also has been installed to track environmental conditions, vehicle system data, and test participant video. The data are uploaded via 4G and WIFI and stored in the cloud. These data will be critical in determining the effectiveness (accuracy, precision) of the DADSS sensors in real-world driving environments and when compared with breath alcohol reference sensors. They will also be used to evaluate the effects of repeated use and vehicle mileage on sensor function and in diverse environments, analyze driver behavior and user acceptance, analyze and assess the impact of the DADSS sensors using real-world data, improve awareness of in-vehicle alcohol detection systems and assess potential impact of the sensors on alcohol-impaired driving. The findings will be used to refine the DADSS Performance Specifications and ultimately for modifying the systems designs and enhance product development. The DADSS technology, if proven to be reliable and reproducible under diverse environmental and biological conditions, would represent a significant technological breakthrough in crash avoidance and a significant advance in driver monitoring technologies in vehicles.

Alcohol-related traffic crashes and deaths remain a major problem in the United States as data indicate that there are approximately 37,000 traffic fatalities yearly, with 30% (~11,000) of them alcohol related. The Automotive Coalition for Traffic Safety (ACTS) and the National Highway Traffic Safety Administration (NHTSA) entered into a Cooperative Research Agreement to explore the feasibility of using passive technologies as an in-vehicle alcohol detection system that is less intrusive than ignition interlocks, but still able to reduce the incidence of drunk driving. Two passive technologies (TruTouch™ and Senseair™) were tested against breath (Alco-Sensor-FST™) and venous blood under a number of environmental scenarios in which individuals engage every day. A total of 92 healthy male and female volunteers (age 22-38) signed an IRB-approved informed consent and participated in experiments in which they consumed 0.9 g/kg of alcohol under a variety of drinking regimens and scenarios that mimicked real-life situations. The volunteers then provided passive breath and tissue (finger touch) samples and had their blood drawn at 5 min intervals for quantification of alcohol via gas chromatography. Lag time of appearance of alcohol, peak concentration, time to peak, and elimination rate were the primary dependent variables. The overall aim of the experiments was to test whether the alcohol concentrations measured by the two prototype devices correlated with venous blood under the following scenarios: lag time, eating a snack, eating a full meal, exercising, and “last call.” Each scenario was simulated in the experimental laboratory. The lag time experiment revealed that the order of alcohol appearance after drinking was (from first to last): breath, blood, and tissue, although early breath samples were contaminated by mouth alcohol. However, with over 4,000 matched points, the concentration-time curves for both prototypes paralleled that of blood with correlation coefficients of 0.7876 and 0.819 for touch- and breath-based technologies, respectively. Similar profiles were observed in the “last call” experiment with a “surge” of alcohol being observed after an extra drink was consumed during the distribution phase. The exercise scenario revealed similar profiles, and finally, the two eating scenarios indicated that blood alcohol concentrations (BAC) were lower after consuming a meal compared to a snack; the breath and tissue samples paralleled this profile. The data not only support the proof-of-concept that two different passive technologies (breath and tissue) can detect alcohol fast enough to be useful in a motor vehicle environment, but extend the parameters by demonstrating that the measurement of alcohol in the human body is not affected by many of the common scenarios that are known to alter blood alcohol concentrations. The passive devices each tracked the time course of BAC regardless of the situation demonstrating that these two compartments provide a high degree of accuracy while at the same time minimizing the disruption to the driver. These two devices, if proven to be reliable and with reproducible results under additional environmental and biological conditions, represent a significant technological breakthrough in strategies to reduce alcohol-impaired individuals from driving a vehicle and causing injuries and/or deaths.

The Driver Alcohol Detection System for Safety Program – a joint effort of the National Highway Traffic Safety Administration and the Automotive Coalition for Traffic Safety – has been developing unique, in-vehicle alcohol detection systems to more effectively address the problem of alcohol-impaired driving. These technologies, both breath-and touch-based, are intended to be seamless with the driving task, non-intrusive, accurate, fast, reliable, durable, and require little or no maintenance. Now in Phase III of development, the breath- based technology is ready for real-world road testing in a naturalistic setting in the State of Virginia, U.S.A. The Driven to Protect Powered by DADSS initiative, is a partnership with the Virginia Department of Motor Vehicles Highway Safety Office and the Automotive Coalition for Traffic Safety. As the technical and program management lead, KEA Technologies, Inc. has instrumented and deployed a small fleet of pilot test vehicles to examine the data from breath-based prototype sensors under various environmental, driver/user interaction, and user demographics conditions. The alcohol detection system is known to be accurate, precise, reliable, and maintainable based on laboratory and controlled test results. This pilot program seeks to obtain data from naturalistic, uncontrolled test conditions. The pilot program will determine if: a) the system is generally accepted by drivers, b) there are any technical modifications required to significantly improve the system, and c) the system is ready for wider implementation in fleet, privately-owned, commercial, or other vehicles. Four 2015 Ford Flex “For Hire” commercial livery service vehicles have been instrumented with in-vehicle breath- based alcohol detection sensors including supporting data collection and transmission systems. The Pilot Deployment Project is ongoing with a goal of collecting at least 15,000 data points from the sensors. Lessons learned will be used to refine the performance specifications, sensor technology, and data acquisition systems for future on-road vehicle testing.

The objective of the present investigation performed within the Driver Alcohol Detection System for Safety (DADSS) program is to demonstrate the effect of further recent improvements of the breath-based nondispersive infrared sensor technology in realistic settings. More specifically, sensor systems installed in vehicles have been tested by: a) exposing them to a controlled, realistic breathing pattern from artificially generated gas pulses mimicking that of an intoxicated driver and b) human subjects entering a test vehicle and performing a simulated drive while under the influence of alcohol. The tests with artificial gas pulses correspond to human directed forced exhalation from positions up 70 cm from the sensor. The tests provide experimental evidence that in-vehicle, driver breath alcohol determination is feasible with a single sensor positioned at the top of the steering column. The human subject study was designed to test both active and passive detection modes. Good correlation to the breath alcohol reference instrument was found in both cases over the full range of alcohol intoxication exceeding 0.08 percent (the legal limit in most U.S. states). Time to detection is a remaining challenge of the passive mode but is manageable by requesting an active breath in the absence of reliable data. The results illustrate the feasibility of using breath-based NDIR based sensors in different operational modes. In the active mode, a simple exhalation directed towards the sensor is enough for a test to be approved and the alcohol content quantified. In the passive mode, the operator does not actively interact with the sensor. In a real-world scenario, sensors set to a passive mode could be used for driver monitoring and to assist the driver to choose a smarter option when alcohol is detected. The overall conclusion from the present investigation is that in-vehicle breath-based alcohol determination is feasible with the current state of the art sensor technology.