After having one beer, it is generally recommended to wait at least one hour before driving. This is based on the assumption that one standard drink contains 12 ounces of regular beer, which has a alcohol content of approximately 5 percent. Therefore, if a person consumes one standard drink within one hour, the resulting blood alcohol concentration (BAC) is likely to be below the legal limit of 0.08 grams per deciliter (g/dL).
It's important to note, however, that individual differences can influence alcohol metabolism and the rate at which the body processes alcohol. Additionally, if you consume additional drinks within the same timeframe, the overall alcohol concentration in your blood may increase, which could affect your ability to drive safely.
Ultimately, the only way to ensure your BAC is below the legal limit is to avoid drinking any alcohol before getting behind the wheel. If you have plans to drink, it is advisable to arrange for a ride home or designated driver to ensure you arrive at your destination safely.