Shelley Bridgeman: New drink-drive limits

if you're not the sort of person who can enjoy just one drink in a social setting, then total abstinence from alcohol prior to driving just might be the answer. Photo / NZME

I love a good breathalyser story. My own starts like this: Years ago I'd been at a wedding reception in Devonport. It was maybe 9pm and I decided to head home to get some work done. I guess I'd had four glasses of wine over about five hours. I'd had dinner too so I wasn't anticipating any problem.

Then at Takapuna, as I was about to get onto the motorway heading south, I realised police were breath-testing drivers. I might have been reasonably confident that I was under the limit but I didn't really want to put that belief to the test so I did a rapid U-turn.

But the New Zealand police are not stupid. A separate police car with two officers was conveniently positioned facing the other way. They were just waiting to catch anyone trying to evade the breath-testing.

I had to say my name and address into the screening device. Unsurprisingly there was alcohol on my breath. The next step was to blow into the bag - which was way more difficult than it looks. I huffed and I puffed but I couldn't get enough air in. The first policeman was not happy with me.

Then the good cop got out of the vehicle and asked me to try again. This time I had two police officers loudly encouraging me. Finally I completed the task then one of the officers asked me how old I was. "What's that got to do with anything?" I replied. "Well, Madam, if you're under eighteen you're over the limit," he explained. Luckily I was about twice that age at the time so I was fine to drive.

My friend's breathalyser story did not have such a happy ending. She'd had a few drinks and was a bit nervous when stopped for a breath-test. She was pleased to be under the limit and when she was stopped again a few minutes later in a different part of the city she thought she was safe. But this time she was found to be over the drink-drive limit.

Such stories underscore the complexities associated with alcohol levels in our bodies. Many factors can impact on alcohol levels - including the liver's ability to metabolise alcohol, the presence or absence of food in the stomach, the concentration of alcohol in the drink, how fast it is consumed, body type, age, gender, ethnicity and individual tolerance levels. With such a cocktail of factors at play, no wonder people have difficulty assessing whether they're lawfully fit to get behind the wheel.

But, thanks to new legislation (for drivers aged twenty and over) coming into effect ahead of the festive season, figuring out if you're okay to drive is going to become a whole lot harder. On December 1st alcohol limits will be lowered to 250 micrograms of alcohol per litre of breath and 50 milligrams of alcohol per 100 millilitres of blood. (Present levels are 400 micrograms and 80 milligrams respectively.)

I seldom drink and drive but, under the old rules, I had estimated that I could have up to three glasses of wine with a meal and be okay to drive. The reduced levels mean I can have fewer than two glasses with a meal. But my biggest concern is that I am still only guessing that's appropriate. Such hazy estimates might have once been acceptable but with the new reduced limits there is little room for error.

Come December many people will pay the price for inaccurately predicting their alcohol levels. Even if we each had a personal device that could precisely gauge such things, we know it's not a guaranteed measure since the amount of alcohol in our system is a constantly moving target. Fines and demerit points will be inevitable for some.

So if you're not the sort of person who can enjoy just one drink in a social setting, then total abstinence from alcohol prior to driving just might be the answer. This festive season I predict that taxis, sober drivers and non-alcoholic beverages will be in high demand. I also reckon more and more people will chose to imbibe in their own home where they can't fall foul of the law.

What do you think of the new limits? Are your drinking habits likely to change?