Oktoberfest.
The party ends,
the responsibility doesn't.

Maybe not. The celebrations may have finished hours ago, but your body clears alcohol at its own pace. After a big night, alcohol can still be in your system when you wake up, even after a full night's sleep.

Feeling fine doesn't necessarily mean your BAC is zero. Alcohol affects everyone differently, depending on things like your body size, what you've eaten, how much you drank and over how long. How you feel isn't a reliable guide.

The safest plan is to sort out the morning after before the night starts: leave the car at home, line up a lift, or give yourself plenty of time before you drive. A personal breathalyser adds another check on top of that plan. For more on planning ahead, see the TAC's drink-driving guidance.

There's no simple answer. Your liver does most of the work of breaking down alcohol, and you can't speed it up. Coffee, a cold shower, a big breakfast or a sleep won't lower your BAC. Only time does.

That's why rules like "one drink per hour" aren't reliable. Drink sizes vary (a one-litre stein of 5% beer is close to four standard drinks), pours at events are rarely measured, and the rate your body clears alcohol varies from person to person and from day to day.

If you've been drinking, assume it will take longer than you think, and plan the morning after with that in mind.

According to Transport Victoria, the penalties for drink driving can include losing your licence, fines, a compulsory behaviour change program, an alcohol interlock fitted to the vehicles you drive, and a zero-BAC licence condition for at least three years after you're relicensed, for relevant offences.

Police can also suspend your licence on the spot for some offences. The penalties that apply depend on your BAC, your licence type and your history, so check Transport Victoria's drink-driving penalties page for details. Other states and territories have their own rules.

A personal breathalyser is a handheld device that estimates your blood alcohol concentration (BAC) from a breath sample. You blow into it and it gives you a reading within seconds.

It's an awareness tool. It gives you additional information about your BAC, which is especially useful the morning after, when you feel fine but aren't sure. It doesn't replace planning not to drive, and a low reading isn't permission to get behind the wheel.

Personal breathalysers use different sensor technologies. Fuel-cell sensors measure alcohol through an electrochemical reaction that responds specifically to alcohol, which suits consistent, repeatable readings. It's the same type of sensor used in many professional breathalysers, and it's the sensor inside the GT.

Semiconductor sensors are another common technology, usually at a lower price point. Whichever type you choose, look for a device made to the Australian Standard, with local support and a clear calibration service.

Every breathalyser sensor drifts over time and with use, so regular calibration keeps readings reliable. How often depends on the device and how much you use it.

For the GT, follow the calibration interval in your user guide, and book calibration with Andatech's Australian service team. See calibration options.