For the safety of the public, it is extremely important that the drunk driver is removed from driving on the road whilst drunk. A breathalyser is an instrument used by the police for quickly determining a driver’s approximate blood alcohol level. What better way than to have a device that will sample a driver’s breath and decipher accurately whether he or she is driving under the influence of alcohol?

Your blood alcohol level is, unsurprisingly, the amount of alcohol circulating around your bloodstream. Your blood alcohol level is measured in grams of alcohol per hundred millilitres of blood. Any alcohol that a person drinks shows up in the breath because it gets absorbed into the bloodstream. As the blood goes through the lungs, some of the alcohol will move across the membranes of the lung’s air sacs (which are called alveoli) into the air. This happens because alcohol will evaporate from a solution. The amount of alcohol detected in the alveolar air is related to the amount of alcohol in the bloodstream. When a person exhales the alveolar air into a breathalyser, the breathalyzer detects the level of alcohol in the exhaled air very accurately.

It is possible to buy your own breathalyser. This will help prevent an embarrassing meeting with a traffic-officer on the way home from a fun night out. A breathalyser can be bought relatively easily for as little as seventy dollars, and as long as it is used and not forgotten, could prove to save its worth in coin. Owning your own breathalyser is much more accurate than keeping track of how many standard drinks you have had – particularly if your host doesn’t serve drinks in standard sizes.

If you use your own breathalyser, then remember to wait for more than ten minutes after your last drink before using your breathalyser. This will make sure all the alcohol in your mouth has been washed away by saliva – or a non-alcoholic drink. If you use your breathalyser immediately after drinking, it will give you a falsely high reading, even if you’ve only had a single mouthful of light beer.

The breathalysers used by the police are also sensitive to “mouth alcohol”, so if less than ten minutes have passed since you had a single mouthful and you get pulled over for a breath test, you may fail it (stories circulate about Catholic priests failing breathalyser tests after celebrating Mass). If this occurs, then you will be taken for blood testing. If the blood test confirms the high reading of the breathalyser, you’re going to cop it. If it doesn’t, then you’ll be OK.
We hope that helps answer the question ‘What is What is a Breathalyser?’!

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