Orange County's DUI Queen
Our DUI Blog Stay Current With DUI Related News

What is Blood Alcohol Concentration?

Blood alcohol concentration, or BAC, is a measurement of alcohol intoxication used for legal purposes. BAC determines the ratio of alcohol to blood in a person's body. For example, a BAC of .10 percent means that there is one part alcohol for every 1,000 parts of blood.

If you’ve heard the anti-drinking and driving campaigns or know someone who has been arrested for DUI, it's likely that you've heard the term BAC used before. Not only has it become widely use terminology, but also one of the primary forms of evidence law enforcement and prosecutors will use to convict motorists of driving under the influence.

BAC Limits in California

Even a small amount of alcohol in a person's body can affect judgment and coordination, regardless of whether or not a person is close to reaching the legal limit, which is .08% BAC in California and across the nation. For commercial drivers, the legal limit is .04% BAC and for drivers under the age of 21, it’s just .01% under the state’s “zero tolerance law.”

The more alcohol that is consumed, the more a person will be affected. As such, BAC readings are crucial components in DUI cases. However, we must note that under California’s DUI law, it is possible to be arrested and convicted of DUI, even if your BAC is under the .08% BAC limit. All that matters is the person’s ability to drive safely was comprised due to alcohol or drug consumption.

BAC differs person by person, and depends on:

  • Gender
  • Body weight
  • Number of drinks consumed
  • Types of drinks consumed
  • How fast the drinks were consumed
  • If food was consumed

Alcohol in the body travels directly to the brain, and cognitive functioning is impaired as a result. Since cognitive functions control much of driving, such as hand-eye coordination and quick decision making, an increased crash risk is associated with a higher BAC. This is why BAC legal limits were created.

When a person is pulled over on suspicion of driving under the influence, law enforcement will either request a breath, blood, or urine test in order to determine BAC.

Accurate BAC readings – or inaccurate readings – can potentially influence the outcome of cases. As we mentioned earlier, just because a person's BAC is below the legal limit does not mean that they cannot be charged for driving under the influence.

At the Law Offices of Virginia L. Landry, Inc., our Orange County DUI lawyers are experienced in the understanding of BAC, the systems used to determine BAC, and how BAC can be effectively used or challenged during the course of a DUI case. No matter what your BAC level may have been at the time of your arrest, our legal team can review you case to determine how we can help.

Contact us today to discuss your case in a free consultation.