Blood Alcohol Concentration (BAC) refers to the percent of alcohol (ethyl alcohol or ethanol) in a person’s blood stream. A BAC of .10% means that an individual’s blood supply contains one-part alcohol for every 1000 parts blood.

Blood Alcohol Concentration, is a term generally used to determine a person’s intoxication level.  In Texas if your BAC is .08% or greater, the law considers you intoxicated.  You may be considered intoxicated if you demonstrate that you do not have your proper physical faculties, even if you are below .08%.

Your DWI attorney advises that you do not agree to provide a sample to test your BAC.  It is easier to defend you if there is not a chemical test to use against you.

Alcohol and Blood Alcohol Concentration

How much alcohol does it take to reach a .08% BAC?  Each of us metabolizes alcohol differently.  Generally, a person can have one beer, glass of wine, or 1 oz. of liquor an hour without being considered intoxicated.  For a person who weighs 140 lbs., four drinks in one hour will place you over .08% BAC.

Do not rely upon a specific number of drinks.  There are other factors that affect your blood alcohol concentration.

Factors that impact BAC

A number of factors will affect your blood alcohol concentration.  They include:

  • Number of standard drinks 
  • Amount of time taken to consume the drinks
  • Your weight
  • Water composition
  • Enzyme production and levels
  • Your sex and corresponding hormone levels
  • Medications
  • Food that you have eaten during the same time period

People process alcohol differently.  As seen by the above list, you may even process alcohol differently each time that you drink.


At MLF Legal our advice is that if you have been drinking, don’t drive.  If you do and have been arrested for DWI, get legal help right away.