Understanding Alcohol’s Effects on Driving

A lot of people are ignorant of alcohol’s effects of driving and are completely unaware that even small amounts of alcohol can cause impairment.

At a blood alcohol content (BAC) of 0.01% to 0.03%, there are hardly any noticeable effects. Impairment is not even noticeable except with special tests that detect subtle effects. Once you start going over 0.03%, that is when you begin to feel the effects. The most common effects at that blood alcohol content are mild euphoria and relaxation. There may also be some loss of inhibitions. Impairment is only limited to concentration. Once your blood alcohol content gets up to around 0.06% to 0.09%, this is when you start seeing serious impairment. Depth perception suffers, which means drivers cannot properly perceive what they’re seeing on the road in three dimensions, such as the distance of an object, vehicle, or pedestrian. Peripheral vision is decreased as well, limiting what the driver can see off to the sides. Another serious impairment is the increased duration of glare recovery. This is especially noticeable at night when facing bright street lights or headlights of oncoming traffic.

Because of this, there are almost no jurisdictions in the world which allow people to legally drive with a BAC above 0.08%, and many set the limit even lower. The only notable exception is the Cayman Islands, which sets the BAC limit to 0.1%. In the State of California, the BAC limit is 0.08%.

Does drinking coffee help combat the effects of alcohol? In a word: no. While caffeine’s stimulating effect may appear to stem the effects of alcohol, it only makes you more awake, not more alert. With a BAC of 0.08% or higher, you will still be impaired even after drinking a cup or two of coffee. The dangerous thing about mixing caffeine with alcohol is that people end up feeling like they are fine to drive because they don’t feel alcohol’s drowsy effects. But in reality, they are still impaired and are still a danger on the road.