Driving (and even biking) under the influence of alcohol is a serious offense in California. Both state and local police are well aware that visitors to Wine Country might have overindulged and they will often be on the lookout for erratic driving or speeding in popular wine-tasting areas on busy weekends.

The blood alcohol limit for driving in the state is 0.08 percent, a level you can reach very quickly in a tasting room. Most wineries will pour about one ounce of wine per taste (some might be stingier, but use one ounce as a guideline), which means that by visiting one winery and tasting (and swallowing) four wines you will already be well on the way to that limit.

People weighing less than 150 pounds who taste another flight of four wines at another winery in a two-hour period will likely be at their legal limit already. Those over 150 pounds will have a little more leeway, but not much.

The penalties for a DUI conviction are severe, including a fine ranging $200-$7,000 and time in jail, not to mention the potential loss of your driving license and a big jump in insurance premiums if you are able to get it back. If you are a driver involved in an accident that causes bodily harm while your blood alcohol over the legal limit the penalties are even more severe.

Trying to calculate how much can be drunk before reaching the limit is a notoriously inexact science. It depends not only on how much alcohol is consumed but also the person’s weight, gender, metabolism, and how much food has been consumed over the previous few hours. Drinking a lot of water while tasting might ward off headaches but will do little to lower the blood alcohol level.

The only way to guarantee you are safe to drive is to drink no wine at all. Instead, use a designated driver or, if that’s not an option, learn to spit wine out after smelling the aromas and swirling it around your mouth. If you really want to experience the lingering aftertaste of a $100 cabernet, then swallow just one or two wines out of all those you taste. There are usually plenty of spitting containers on tasting room counters. Just double-check that it’s not the water jug you’re about to empty your wine into.