**Alcohol** negatively affects the driver even when the blood alcohol level is below the legal limit. Even if a small amount is consumed, alcohol is distributed throughout the body via the bloodstream, primarily affecting the **brain** and **vision**. This can lead to a series of harmful effects:

- **Behavior:** Alcohol can create a false sense of security, leading to taking more risks and making mistakes that can cause accidents. It can also cause the driver to act more aggressively or impulsively.

- **Perception of the environment:** Alcohol affects the ability to correctly see traffic signs and signals, calculate distances, and maintain attention on the surroundings. Additionally, it increases the likelihood of being dazzled by the lights of other vehicles.

- **Coordination and decisions:** Alcohol impairs the coordination of movements and lengthens reaction time. It also increases the likelihood of making poor decisions or not knowing how to execute them correctly.

For these reasons, even if the blood alcohol level is within legal limits, alcohol remains a significant risk factor for traffic accidents. The only completely safe blood alcohol level for driving is **0.0**.