Alcohol and driving (Investigation)

It's Not a Good Idea...

We are all aware of the dangers in drinking and driving, however it’s important to understand how alcohol affects your driving and how authorities determine how much alcohol you have consumed.

The standard measure of the amount of alcohol in your system is Blood Alcohol Content (or BAC).

This measures the number of grams of alcohol in 100 millilitres (mL) of blood.

It’s accepted that alcohol affects men and women differently.

There are a number of factors which affect BAC, namely:

• The person’s mass,
• Their body fat percentage,
• Their Gender,
• Whether they have an empty stomach or not.

In addition to these, BAC is actually calculated using a number of different variables. For men, the formula used is:

And for women, it is:

Here, N is the number of standard drinks the person has consumed, H is the number of hours of drinking and M is the person’s mass (in kilograms).

Note that in calculating the BAC, the only difference between the formulas is the number the person’s mass is multiplied by.

The Standard Drink

This is a standard measure of alcohol concentration in one drink. A drink that has 10 grams of alcohol in it over its volume is referred to as a ‘Standard Drink’.

BAC Limits

In order to be considered ‘fit’ to drive, NSW has 3 standard limits that the NSW Police enforce.

As a measure of how BAC varies with time, your body is able to process approximately 1 standard drink per hour. However, alcohol content won’t peak until up to 2 hours after your last drink.

So as a guide, to potentially remain under 0.05:

MEN- One to two standard drinks in the first hour then one standard drink each hour after that.

WOMEN- One standard drink each hour.

This acts as a rough guide, however any more than this and you risk being over the legal limit.

Be aware that for all Learners, and provisional licence holders in australia, the limit is ZERO BAC!

Effects of Alcohol:

• Impairs judgement, vision and hearing
• Increases reaction time
• Affects coordination

Refer to the RAA website for more information relating to alcohol and driving:

http://www.raa.com.au/page.aspx?TerID=1375

Refer to the Roads and Maritime Services website for information regarding penalties for Drink Driving:

http://www.rta.nsw.gov.au/usingroads/penalties/alcoholanddrugs.html

Exercise

Discuss reasons why alcohol might impact each gender differently.

As a class, come up with a number of explanations on how factors like mass, body fat percentage and an empty stomach may affect a person's BAC.