Portable Visibility Warning System for the Safety of Highways

Visibility is critical to the task of driving and reduction in visibility due to fog, smoke or other weather events such as heavy rain is a major traffic operation and safety concern. In Florida, these conditions could be a result of sudden dense fog, fires (whether wild or controlled), and heavy pockets of rain or hail. Real time measurement of visibility may help in warning the drivers when the visibility falls below certain acceptable levels. Devices measuring visibility are the key toward that objective. This paper reports on the design of a visibility warning and detection system that detects any reduction in visibility below a certain limit that would be considered hazardous for normal traffic flow conditions. This system can also respond accordingly in real time to convey specific warning messages to drivers in an effective way and report this information to the appropriate Traffic Management Center (TMC). The innovation in this system is that it was developed from components that are inexpensive and available commercially. Also, this system can be employed as portable or fixed system. A fixed system might be useful in areas that tend to have dense fog (for example, rural sections of freeways). However, the portable system can be used every time a wildfire occurs close to a highway. The system components and a preliminary testing for the system’s performance are discussed and presented in this paper.