Change of driver's reaction time depending on the amount of alcohol consumed by the driver - the case study

Each driver should drive according to the actual road traffic rules of the country in which he is currently located. The law systems of various states of Europe allow an increased maximal blood alcohol level of driver. As the fact that no small number of road accidents is caused because of the influence of alcohol on the driver, it is necessary to focus the attention of the society on this issue. The paper deals with the influence of alcohol on the reaction time of the driver. The effect of alcohol on driver behaviour has been studied. The reaction time of several drivers from a selected group of people was measured. At first (before alcohol drinking) the physical and mental condition of the drivers was assessed, using a series of question. Subsequently, the measurements were carried out with a sober driver. After this initial measurement the driver began to drink alcohol and after 20 minutes the level of alcohol in driver´s breath was determined by certificated equipment. It followed by starting the vehicle at a speed of approximately 50 km/h and stopping the vehicle in front of the simulated barrier. During the tests of the stopping distance, the mean fully developed deceleration was explored as the supporting variables. As the most important variable was the driver´s reaction time. It was researched by using of the video-analysing from two synchronized cameras. One camera was placed on the windscreen to monitor the situation in front of the vehicle, the other one monitored the movement of the driver´s feet. The aim of this paper is to focus on the fact that there is a dependence between the amount of consumed alcohol and the driver´s reaction time, which significantly affects the road safety. The reaction time of the driver directly influences to the stopping distance thus it is resolute for stopping the vehicle before a barrier