Some experimental results indicate that improvement in road conditions can be demonstrated to disperse or reduce fog and to improve safety and serviceability through aerial or ground seeding. However, more investigation is needed to demonstrate effective and reliable tools to dissipate fog under a variety of climatological, geographic, and road conditions. Programs to reduce fog related collisions in California have demonstrated that morning broadcasts on radio and TV stations during periods of heavy fog and the distribution of fog safety brochures were successful in increasing public awareness. Increased law enforcement presence is thought to be a major factor in improving driver diligence in a heavy-fog situation. Closure of the left lane is a key to maintaining smooth traffic flow as it allows a place for motorists to pull into in the event of a problem.
Secondary accidents are a major problem under driving conditions of reduced visibility.
A system of speed limit and warning signs was used in New Jersey and New Mexico and was thought to significantly contribute to the reduction of secondary accidents by alerting motorists to driving conditions ahead. However, traffic behavior, as defined by average speed and standard deviation in speed, does not appear to change significantly after signs are displayed. The states have also been guided in their efforts by recommendations of the National Transportation Safety Board. Reliance on police patrols to detect limited-visibility conditions will not ensure their timely detection. Although weather forecasts may alert authorities to the possibility of fog formation, they are not sufficiently accurate, comprehensive, or timely to predict that fog will form in a specific area.