Scientific paper ID 2090 : 2021/3

Zornitsa Spasova, Tzvetan Dimitrov

Low visibility is one of the factors for increasing the number of traffic accidents. In the present research we have studied the effect of meteorological events such as fog and mist on the number of road accidents in Sofia, Bulgaria. We compared the number of traffic accidents during days with fog (with visibility below 1 km), mist (visibility from 1 to 10 km) and their number in days with absence of such events. The study period covered more than 1000 dates between October 2001 and February 2009. The results showed that the highest number of accidents occurred on days with mist, followed by foggy days and, expectedly, the lowest average number of accidents was observed in days without such phenomena. The differences in the average number of accidents are statistically significant. The interpretation of this result is related to a change in drivers’ behavior during fog – fewer inexperienced drivers decide to go on the road in such conditions, drivers usually reduce speed and increase the distance between cars in foggy weather. Despite the measures taken, as expected, due to reduced visibility, the number of accidents on foggy days is higher than on other days. Unlike fog, mist is probably an underestimated meteorological phenomenon by drivers and pedestrians.

пътно-транспортни произшествия мъгла димка намалена видимостtraffic accidents fog mist low visibilityZornitsa Spasova Tzvetan Dimitrov


[1] Spravochnaya entsiklopediya dorozhnika. T. 2. Remont i soderzhanie avtomobilnyh dorog/ A. P. Vasilev. M.: Informavtodor, 2004, 1129 s.
( [1] Справочная энциклопедия дорожника. Т. 2. Ремонт и содержание автомобильных дорог/ А. П. Васильев. М.: Информавтодор, 2004, 1129 с. )

[2] Shiryaeva A. V., Meteorologicheskie usloviya funktsionirovaniya avtotransporta na territorii Moskvy i Moskovskoy oblasti, Izvestiya RAN. Seriya geograficheskaya, 2016, № 5, s. 99–106
( [2] Ширяева А. В., Метеорологические условия функционирования автотранспорта на территории Москвы и Московской области, Известия РАН. Серия географическая, 2016, № 5, с. 99–106 )

[3] Abdel-Aty M.,E. Al-Ahad, H. Helai, A Study on Visibility Obstruction Related Crashes Due to Fog and Smoke 12th WCTR, July 11-15, 2010, Lisbon, Portugal

[4] Codling J. P. Thick Fog and its Effect on Traffic Flow and Accidents. Transport and Road Research Laboratory, TRRL Report LR 397, TRRL, 1971, Crowthorne

[5] Cools M., E. Moons, G. Wets, Assessing the impact of weather on traffic intensity. In Proceedings of the 87th annual meeting of the Transportation Research Board. CD-ROM. Transportation Research Board of the National Academies, 2008, Washington, D.C.


[7] Moore R. L., L. Cooper, Fog and Road Traffic. Transport and Road Research Laboratory, TRRL Report LR 446, TRRL, Crowthorne,1972

[8] Musk L. Climate as a factor in the planning and design of new roads and motorways. In: Perry, A. H., and Symons, L. J., (editors), Highway Meteorology, E&FN Spon, London.

[9] Perry, A. H. Environmental Hazards in the British Isles. George Allen & Unwin, London. Cools et al., 2008

[10] Singh A., H. Sood, A Review on Influence of Fog on Road Crash, International Journal of Engineering Research & Technology (IJERT), Vol. 6 Issue 06, June – 2017

[11] Summer R., C. Baguley, Burton J. Driving in Fog on the M4. Transport and Road Research Laboratory, TRRL Report LR 281, TRRL, Crowthorne, 1977




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