What is “blood-alcohol concentration” or “blood-alcohol level”?
Posted on 24. Jun, 2011 by Lawyers in DWI
Alcohol has numerous impacts on the human body. One of the most important, from a physiological perspective and a legal standpoint, is how alcohol exists in the bloodstream. A person’s level of intoxication is measured by what is known as blood-alcohol content (BAC), or blood-alcohol level (BAL). It is this measurement that law enforcement agencies use to determine if someone if publically intoxicated or driving under the influence of alcohol.
All information provided for reference purposes only, contact New Brunswick DWI Attorneys for additional details.
How BAC is Measured
A person’s BAC is measured by how much alcohol is present in their blood as compared to a person with no alcohol. For instance, if a person has a BAC of 0.1, it means that his or her blood has 0.10% of their blood is alcohol – the one tenth of one percent. A BAC of 0.08 is considered to be drunk by most states in the United States, but some states will prosecute individuals at lower levels of intoxication. There are a number of factors that impact how quickly alcohol is absorbed into the bloodstream and how quickly it fades from the system.
Factors Impacting BAC
Men and women absorb alcohol differently. While there are always exceptions, most women cannot metabolize alcohol as quickly as men. Weight also contributes to how quickly alcohol is metabolized – the higher a person’s weight, the faster the alcohol will be metabolized. A 140-pound man will have a BAC of .05 after 2 drinks, while a 140-pound woman will have a BAC of 0.07. One drink is 12-oz of beer, 5-oz of wine, or 1.25-oz of 80 proof liquor.
How BAC is Measured
One way to calculate a person’s BAC is a complex mathematical calculation. This is useful when immediate measurement of BAC is not practical, or to show that what the BAC may have been in the past or will be. There are more accurate ways to measure though, specifically through blood, urine or breath tests. These are more accurate tests, but must be measured as soon as possible to make sure the readings are accurate. One of the most popular methods for measuring BAC by law enforcement personnel is a breathalyzer. These machines measure the amount of ethanol in a person’s bloodstream, and can be done quickly at DUI checkpoints. This technology is also used on Interlock devices that can be attached to an individual’s car to ensure they do not drink whilst under the influence. Breathalyzer’s are dependent on a number of factors, including outdoor temperature, body temperature and breathing patterns. They need to be calibrated precisely for the most accurate readings.
DISCLAIMER: While all this information is accurate, it should not be taken as actual legal advice from a lawyer.
