New Delhi: International Road Federation (IRF), Geneva based global body working for better and safer roads worldwide expressing deep concern at increasing fatal road crashes and vehicle pile ups due to fog, has stressed on the need for safe driving .
“Every winter, dense fog turns highways into high-risk corridors. Reduced visibility, delayed reaction time, and unsafe following distances combine to create conditions where a single braking error can trigger multi-vehicle pile-ups. These incidents are not merely acts of nature; they are predictable, and therefore preventable. Road safety in fog means drastically reducing speed (around 30 km or less). Using low-beam headlights (not high beams), maintaining huge following distances, avoiding sudden braking and lane changes, staying focused , using indicators, and utilizing fog light if visibility drops to zero, safely pull over and wait for it to clear.” said Mr K K Kapila, President Emeritus , International Road Federation (IRF) a global road safety body working for better and safer roads worldwide.
While vehicles today are equipped with better headlights, anti-lock braking systems, and airbags, fog-related accidents continue to occur because safety cannot rely on drivers alone. Under near-zero visibility, even experienced drivers misjudge distance and speed. This is where infrastructure-based safety systems become essential.
Modern traffic management technologies now allow highways to “see” what drivers cannot. Advanced Traffic Management Systems (ATMS) can detect slow-moving or stationary vehicles, identify sudden traffic build-up, and alert control centres in real time. When combined with Variable Message Signs, these systems can warn drivers instantly about fog, advise safe speeds, and encourage minimum following distances—simple interventions that save lives.
Proposed Policy Measures Deployment of Fog-Responsive Detection Systems Strict enforcement of speed limits and minimum safe following distance between moving vehicles should be ensured during normal weather conditions. During foggy conditions, mandatory reduction of speed limits must be implemented and clearly communicated to motorists through Variable Message Sign Boards installed at regular intervals along highways.
Adoption of Time-of-Flight (ToF) sensors based on LiDAR or Light Detection and Ranging, a remote sensing technology that uses light in the form of a pulsed laser to measure ranges (or variable distances) of a sensor, to identify identify fog-prone stretches and accident black spots.
Integration of such systems with ATMS for real-time monitoring of vehicular movement and detection of stationary or slow-moving vehicles under low-visibility conditions.
Strengthening ATMS and VIDES Capabilities Mandatory utilization of Video Incident Detection and Enforcement System (VIDES) as part of ATMS, in line with NHAI Policy Circular No. 11.53/2023 dated 10.10.2023.
Configuration of VIDES algorithms to automatically detect poor visibility conditions such as fog or smog and generate alerts for traffic operators. Linking visibility alerts with operational responses such as speed advisories, lane control, and emergency response deployment.
Dynamic Driver Information and Speed Management with Installation of Variable Message Signs (VMS) on fog-prone highway stretches to display real-time visibility warnings, speed advisories, and safe following distance instructions.
Standardization of fog-specific signage indicating minimum safe distance between vehicles at design speed.
Interface with Vehicle Safety Technologies for Encouragement of compatibility between highway infrastructure systems and vehicle-based Advanced Driver Assistance Systems (ADAS), where feasible. Issuance of advisories promoting adoption of anti-collision and fog-assist technologies in vehicles using access-controlled highways