RT Journal Article SR Electronic T1 2A.003 Potential crash-risks for vehicles in staggered car-following on multilane-highways under low-density conditions JF Injury Prevention JO Inj Prev FD BMJ Publishing Group Ltd SP A12 OP A12 DO 10.1136/injuryprev-2021-safety.35 VO 27 IS Suppl 2 A1 Pranab, Kar A1 Suvin, PadinjareVenthuruthiyil A1 Mallikarjuna, Chunchu YR 2021 UL http://injuryprevention.bmj.com/content/27/Suppl_2/A12.1.abstract AB The challenges associated with evaluating the traffic flow quality on multilane highways are manifold. Better quality of driving is achieved when mobility and safety are optimally traded-off. The majority of the studies on Level of Service (LOS) have primarily focused on the improvement of travel time, or travel speed by minimizing the travel delay. However, the safety aspect/risk-taking behavior of drivers remains ignored. Rear-end crashes are the most frequently occurring one that accounts for about 29% of all the crashes and resulting in a significant number of injuries and fatalities each year. The presence of slow-moving vehicles in highspeed highways would lead to car-following situations even in lower density conditions, which impart potential crash risks. The current study evaluates the risky behavior of drivers by identifying the potential conflict between the leading and lagging vehicles. The study performs both macroscopic and microscopic diagnosis with the help of detailed trajectory as well as detector data. We analyzed the variability in both speed and acceleration characteristics of drivers corresponding to a potential conflict scenario. The conflict points were identified by using the surrogate safety measures termed Time-to-Collision (TTC) and Stopping-Sight-Distance (SSD). Results indicate that even under low-density conditions, the potential risk of rear-end crash is high due to the presence of significant slow-moving vehicles. The acceleration characteristics indicate that many drivers accept potentially risky maneuvers under the presence of slow-moving vehicle ahead. The crash potential due to such a situation could be minimized by regulating the designated lanes for slow-moving vehicles.