How do you calculate blood alcohol content?

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Calculating Blood Alcohol Content is an important factor in determining one's level of intoxication. There are a few elements to calculate this effectively, such as your weight, gender, how many drinks you've had, and how much time has passed since your last drink.

Widmark Formula

The Widmark formula is an equation used to calculate the estimated blood-alcohol concentration of a person after consuming alcoholic beverages.

Developed in 1932 by Erik Widmark, it is one of the most accurate and widely used methods to determine a person's blood-alcohol levels, as well as their theoretical intoxication levels. It takes into consideration a number of factors including rate of metabolism and absorption, body weight and the amount consumed. Once applied, the results provided can be used to assess whether an individual has reached the legal limit for driving or any other activities related to alcohol intake.

As such, it stands as an essential resource to ensure that individuals don't place themselves in unsafe situations regarding intoxication levels.

The Widmark formula is as follows:

Blood Alcohol Content = [ (Alcohol consumed in grams / (Body weight in grams x r) ] * 100

r = 055 (Females)

r = 0.68 (Males)

How many drinks does it take?

Knowing how many drinks to limit yourself too in order to remain at a specific blood alcohol level can be complicated and varies depending on a number of factors. It is important to understand that when consuming alcohol, a person's alcohol levels can rapidly increase with the number of drinks they consume.

Your alcohol level after example 5 drinks depends on many factors, such as gender, body weight and size, and rate of consumption. Generally speaking, 5 drinks could result in a blood alcohol content of approximately 0.105% for a 95kg man or 0.171% for a 70kg female, which indicates extreme intoxication.

Blood alcohol content chart

Below you can find a list of the amount of drinks you would need to consume in order to reach an approximate blood alcohol level.

Written by Angela Mosel Angela Mosel is a substance abuse social worker with a Bachelor of Social Work from Spring Arbor University.

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