How Blood Alcohol Concentration (BAC) Affects Driving Ability

Published on Apr 14, 2023 at 5:16 pm in Car Accidents.

How Blood Alcohol Concentration (BAC) Affects Driving Ability

Celebrating a birthday, college graduation, or wedding with a drink is a common practice that many Mississippi residents participate in. While there’s nothing wrong with toasting to the goodwill of friends and loved ones, it can become a problem when a person decides to get behind the wheel of a motor vehicle after a night of drinking.

Most people underestimate how much alcohol has affected them and overestimate their driving abilities. At Pittman Roberts & Welsh, PLLC, we would like to stress the importance of not driving after drinking. If you remain unconvinced, consider the ways in which blood alcohol concentration (BAC) affects driving ability.

Don’t forget that you don’t have to feel drunk or intoxicated to be under the influence of alcohol. Even one or two drinks can increase your BAC to an unsafe or illegal level for driving.

How Is BAC Measured?

Blood alcohol concentration is measured as the percentage of alcohol that is present in a person’s bloodstream. A person who has a .10% BAC has one part alcohol for every 1,000 parts blood.

There are many methods for detecting and measuring a driver’s BAC, including breath, blood, and urine tests. Breathalyzer tests are perhaps the most well-known, as they can easily be administered by a police officer during a traffic stop or at the scene of an accident. Drivers who refuse to take a breathalyzer test might be ordered to undergo blood or urine analysis by a judge.

Take note of the levels at which a driver is considered intoxicated in the state of Mississippi:

  • Non-commercial drivers – .08%
  • Commercial drivers – .04%
  • Drivers under the age of 21 – .02%

If a driver is found to be operating a motor vehicle under the influence of alcohol, they may face criminal consequences, including arrest, a fine, and jail time. Unfortunately, far too many drunk drivers only face these consequences after they have already caused an accident.

How BAC Affects a Person’s Ability To Drive

The research is clear—alcohol negatively impacts a person’s driving abilities. Alcohol slows reaction times and impairs judgment, two skills that are critical to safely operating a vehicle. Let’s take a closer look at the impact that different BACs can have on driving:

  • .02-.04% – Sense of warmth, feelings of relaxation, minor judgment impairment.
  • .05-.07% – Lowered inhibitions, exaggerated emotions, impaired memory and reasoning skills.
  • .08-.10% – Problems with balance, vision, and speech. Slowed reaction times, impaired judgment, lowered self-control, fatigue.
  • .11-.15% – Gross motor impairments, severe judgment and perception impairments, feelings of depression and anxiety.

It is important to remember that alcohol affects every person differently. One person with a BAC of .08% could appear calm and in control of themselves despite suffering from severe impairments, while another individual with a BAC of only .02% could be dizzy, nauseous, and struggle to stay upright.

Factors that influence a person’s BAC and the impact of drinking include:

  • Weight and height
  • Number of drinks
  • Type of alcohol
  • Period of drinking
  • Presence or absence of food in the stomach
  • Fitness level
  • Emotional state
  • Metabolic rate
  • Past alcohol consumption

What To Do if You’ve Been Out Drinking

At Pittman Roberts & Welsh, PLLC, we recommend that you make a safety plan every time you intend to drink alcohol outside of your own home. This could include:

  • Having a designated driver
  • Using a taxi or rideshare service
  • Using public transportation
  • Staying over at a friend or family member’s house

Never drive drunk, and never get into a vehicle with a driver who has been drinking.

Why Are Drunk Driving Accidents So Serious?

Drunk driving accidents tend to be much more destructive than crashes involving two sober drivers.

Since intoxicated drivers tend to have poor judgment and reasoning skills, slowed reaction times, and lowered self-control, they are much more likely to speed and engage in risky behaviors. Accidents at higher speeds typically result in much more severe injuries and property damage. A drunk driver is also less likely to notice a hazard and apply the brakes to avoid a collision.

Drinking can also make drivers feel drowsy or fatigued. Falling asleep at the wheel is a risk a person takes when they choose to drive drunk.

It’s no secret that driving while under the influence of drugs or alcohol is dangerous, though. Campaigns intended to curb the rate of drunk driving have been aimed at motorists for the past several decades, starting in 1983 when the National Highway Traffic Safety Administration (NHTSA) partnered with the Ad Council to run a campaign titled “Drinking & Driving Can Kill a Friendship.” That year, drunk drivers caused approximately 50% of all traffic fatalities.

Today, drunk drivers cause around 30% of all traffic deaths in the United States. In 2020, 11,654 people were killed by drunk drivers—about one death every 45 minutes.

Life After a Drunk Driving Accident

For many victims, life after a drunk driving accident will forever look different than before. Serious injuries can require months, years, or even a lifetime of medical care. You may have to take time off work to recover, and for some people, going back is never an option. Severe depression and anxiety are not at all uncommon, and post-traumatic stress disorder (PTSD) related to the accident can make traveling by vehicle difficult.

If you’ve been injured by a drunk driver in Jackson, you have rights. An attorney from Pittman Roberts & Welsh, PLLC will sit down with you for a free, no-obligation consultation to explain your legal rights and options to you as clearly as possible.

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