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Does the One Drink Per Hour Rule Work?

Many people learn about the "one-drink-per-hour" rule when they are younger and begin to start drinking alcohol with friends. The general rule is that you can stay under the limit if you keep your alcohol consumption to one drink per hour. However, over time, you may realize that you can feel different even if you stick to the rule. 

The one-drink-per-hour idea is more of a guideline or recommendation than a rule to live by. Drinks can impact different people in different ways. There are a lot of factors that impact your ability to drive safely after drinking. If you do end up under arrest for impaired driving in Oakland or the East Bay, call a California DUI lawyer as soon as you can so you can fight to keep a DUI off your record.

Number of Drinks and the Legal Limit in California

The legal limit for most drivers in California is below 0.08% blood alcohol content (BAC). For commercial drivers, the limit is even lower, at 0.04% BAC. For underage drivers, there is a zero-tolerance policy for drunk driving and any amount of alcohol in the blood is prohibited. 

If a driver is found with a BAC of 0.08% or higher, they can face a per se DUI. Under California Vehicle Code 23252(b), a per se DUI is driving with a BAC of 0.08% or higher, even if the driver did not appear impaired. 

The magic question for drivers who are having a couple of drinks is: How many drinks does it take to stay under the legal limit? 

One Drink Per Hour Rule of Thumb

The one-drink-per-hour rule has been in the heads of drivers in California ever since they got their first driver's license. The California Department of Motor Vehicles (DMV) even has a BAC chart in the California Driver's Handbook
Blood Alcohol Content Chart from California DMV

First, take into account body weight and gender. Men and women tend to absorb alcohol at different rates because of liver volume and body fat. According to a study published in the National Institutes of Health, "In general, women have less body water than men of similar body weight, so that women achieve higher concentrations of alcohol in the blood after drinking equivalent amounts of alcohol."

For example, a man who weighs 200 pounds may be able to have 2 drinks and still be under the limit but a woman who weighs 140 pounds would likely be over the limit after two drinks.

Time is also a factor as the body metabolizes alcohol, eliminating it through the body after breaking it down in the liver. According to the DMV chart, you can subtract 0.01% for every 40 minutes that lapse between drinks. 

Another study finds "Alcohol leaves the body at an average rate of 0.015 g/100mL/hour, which is the same as reducing your BAC level by 0.015 per hour." This means that if you go to bed at 2:00 a.m. with a BAC of 0.20% and drive to work at 9 a.m., you may still be over the limit with a BAC of 0.095%.

Not All Drinks Are Created Equal 

The idea that most beers are 5% alcohol is outdated, especially for craft beer drinkers in California. A study shows that the national average ABV of beer has increased over the past couple of decades. California's biggest craft brewery favorite, Sierra Nevada Pale Ale is 5.6% alcohol. Another popular craft beer from California, Lagunitas IPA is 6.2%, while Stone IPA is 6.9%.

Many beer drinkers are also drinking in 16-ounce pints or pours of more than 12 ounces. If someone is making cocktails at a house party or pouring their own wine, the cocktails may have more than 1.5 ounces of liquor and wine pours may be larger than 5 ounces. Generous servings can make one drink more like 1½ to 2 drinks under the old rules.

What Other Factors Impact Alcohol Level Rates?

Alcohol and time aren't the only factors in a driver's blood alcohol level. Old suggestions of drinking coffee, taking a cold shower, or even "hair of the dog," will not help you metabolize alcohol faster and hair of the dog will do the opposite. Drinking water and having food in your stomach before you drink can slow absorption and help you avoid some of the worst impacts of a hangover but will not do much to speed up your metabolism. 

Some medications can increase the impairing effects of alcohol and impair safe driving after only one or two drinks. Make sure you understand how any medications may affect you before combining them with alcohol on a night you plan to drive. Drivers can get a drug DUI even for prescription drugs if it impacts their ability to safely operate a vehicle. 

Did You Get a DUI After Only a Couple of Drinks?

Just because you were arrested for a DUI does not necessarily mean you were over the limit. Those roadside breath tests that show you're over the limit can be very inaccurate. Preliminary alcohol screening (PAS) breath tests are not used as evidence of your BAC level in court. This is why the police also have you submit a breath test sample after arrest. Even these more sophisticated breath-testing machines can be inaccurate.

Your East Bay DUI defense attorney is familiar with the problems with these breath tests and understands how to challenge the results in court. The police may have improperly conducted and observed the test. The machines may not have been properly maintained and calibrated. An inaccurate breath test result should not result in jail time when the police failed to follow the rules. 

Talk to an East Bay DUI Defense Lawyer About Your Case

Lynn Gorelick has more than 39 years of East Bay DUI defense experience and understands how much is at stake after a DUI arrest. She understands how to approach the individual facts of each case for the greatest chance of success to keep her clients out of jail. If you are facing DUI charges anywhere in Oakland, Alameda County, or Contra Costa County, contact Lynn Gorelick.

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