How accurate are digital breathalysers?

This will come down to the quality of the breathalyser and the quality of the sensor contained within it. Breathalysers NZ range of fuel-cell electrochemical units are extremely accurate and also read to one thousandth of a decimal point.  Our range of semi-conductor units will give you an estimate of your %BAC to one hundredth of a decimal point.

When buying a breathalyser always buy a reputable brand from a reputable dealer. If you can’t find information about the make and model through internet searching for it internationally then you are not purchasing tried and tested. Also the majority of major brands have had replicated units created of their products. If you want quality assured then you must buy from the manufacturers nominated supplier.


What is BAC?

%BAC is short for Blood Alcohol Content (or Breath Alcohol Content). It is a measurement of weight per unit of volume. Understanding readings can be difficult in New Zealand as there are different methods of interpretation. In NZ we have mcg per litre of breath (mcg/L) and mcg per 100ml of blood. The international standard however is %BAC (including Australia) and we have found that this is the easier format for the majority of people to understand. For this reason Breathalysers NZ sends all models out in %BAC whether than can be changed to mcg/L or not.


How long must I wait before using my breathalyser?

We recommend 20 minutes after your last alcoholic beverage to be safe. Shorter times than this can mean that alcohol is sitting in the mouth, throat or stomach and has yet to be absorbed into the blood. Either of these situations will mean that the breathalyser result will be higher than your actual %BAC and therefore inaccurate.

An easy way to tell if your BAC is rising or falling is to test yourself at 5 minute intervals. Once falling it will not rise again until additional alcohol is consumed.


What are the NZ drink driving limits?

From 1 December 2014 the alcohol limit for drivers aged 20 years and over lowered from 400mcg of alcohol per litre of breath to 250mcg. The blood alcohol limit lowered from 80mg of alcohol per 100ml of blood (0.08), to 50mg (0.05). Under 20 year olds cannot have any alcohol present when driving.

Interpreting your breathalyser results:

  • Between 0.051% – 0.08% BAC (250 – 400mcg of alcohol per litre of breath) = up to a $700 infringement + 50 demerit points + no criminal conviction.
  • Above 0.08% BAC (400mcg of alcohol per litre of breath) = criminal conviction.

For further information please see http://www.transport.govt.nz/land/bloodalcoholqanda/


How do I pair my smartphone with my breathalyser?

The Bactrack Mobile & BACtrack Vio

In order to use the BACtrack Mobile or Vio you will need to download the BACtrack app from the App Store or Google play onto your smartphone. You can find it by searching “BACtrack”.

The first time you use the device you will need to pair it with your smartphone. Make sure you have Bluetooth turned on in the phones settings to do this.

Note: The best way to use The BACtrack Mobile or Vio each time is to open the app first and then turn on the device.


What should my personal breathalyser be used for?

Personal breathalysers are designed to help individuals understand their Breath Alcohol Content. As technology moves ahead they are being used increasingly from a personal well-being perspective. Certain Bluetooth connected model breathalysers enable functionality such as the tracking, graphing and averaging of alcohol consumption over time.

Some individuals choose to use breathalysers to determine whether or not it is safe for them to drive. All Breathalysers NZ  breathalysers are for the purposes of indicative testing only. They cannot dispute the results of an official test and they cannot be used as evidence in a court of law. Neither the manufacturer, distributor or retailer will be held responsible for inappropriate use of any of Breathalysers NZ products.


Why do we have different readings yet we have had the same amount to drink?

It is in fact more likely than not for two people who have consumed the same amount of alcohol, in the same amount of time, to have two different readings. BAC content is affected by gender, weight, age, metabolism, food and liquid consumption (to name a few). Results will also change from one day to the next with the same individual. This is why it is so important to have a breathalyser to test yourself. No breathalyser = no certainty.


How do I get hold of additional mouthpieces?

We stock a full range of additional mouthpieces. You can order these through the site by going to the PRODUCTS pages. Your unit will generally come standard with either 3, 5 or 6 pieces. All mouthpieces can be reused but please ensure that you keep them hygienically clean and that the airway remains clear. Mouthpieces are dishwasher friendly.


What factors affect my BAC?

Few people understand the variables involved in how your body processes alcohol. There is a common misconception that I can have x number of drinks and be safe to drive. Here is a little interesting info:

  • The number of drinks. The more you drink, the higher the BAC.
  • How fast you drink. When alcohol is consumed quickly, you will reach a higher BAC than when it is consumed over a longer period of time
  • Your gender. Women generally have less water and more body fat per pound of body weight than men. Alcohol does not enter fat cells as easily as other cells, so more alcohol remains in the blood of women.
  • Your weight. The more you weigh, the more water is present in your body. This water dilutes the alcohol and lowers the BAC.
  • Food in your stomach. Absorption will be slowed if you’ve had something to eat as the alcohol will have less direct contact with the stomach lining.


What is the difference between a semi-conductor and electrochemical (fuel cell) sensor?

Breathalyser sensor technology has advanced from purely semi-conductor to the use of electrochemical sensors as well in recent time. Quality electrochemical (fuel cell) sensors are more precise and hold their accuracy substantially longer than semi-conductor sensors. They are also more expensive however. That being said good quality semi-conductor sensors still have fairly high accuracy and will last at least 50 tests / 9 months before requiring calibration


Why do I have to wait to use my digital breathalyser after turning it on?

When you first turn your breathalyser on it will need to warm the units sensor up to approximately the same temperature as your breath, which is around 34 degrees celsius. Times will range from 5 – 45 second depending on the quality of sensor that you have purchased. This needs to happen to ensure accuracy of the reading. If the warm up time becomes very slow then this is an indication that there is residue alcohol build up on the sensor and it is time for recalibration.


How come I have drunk alcohol and still get a 0% reading?

Smaller amounts of alcohol (1-2 standard drinks in an hour for example) may be processed and eliminated by the body quickly or completely. Factors are dependent on individual constitution however so this is not necessarily the case. Your BAC will only continue to rise once your body can no longer process the amount of alcohol consumed. ie: past saturation point.


My result came back just under the limit. Am I safe to drive?

If in doubt then do not drive, the risk is not worth it. Alcohol can take up to an hour to be absorbed into the blood stream meaning your BAC can rise for up to an hour after your last alcoholic beverage. A good way to know if you BAC is still rising or falling is to re-test yourself at 5 minute intervals.


Why does my unit give an error message when I blow into it?

Errors can happen for several reasons such as:

  • The battery power is too low to conduct a test.
  • Your sensor has alcohol build up and requires calibration.
  • Flow errors. Restart the unit and blow consistently through the mouthpiece.
  • If you are unsure then please contact us.


Why is my breathalyser having trouble powering up?

Make sure that you are using alkaline batteries. Carbon batteries may not have enough power to start the unit up. Also be conscious of rechargeable batteries as some have different voltages.