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Types of Breathalysers

What is a Breathalyser? What is its purpose?

A breathalyser is a device used to quantitatively measure the concentration of alcohol in an individual’s blood, otherwise known as the Blood Alcohol Content (BAC) in their system. It is difficult to determine at what point an individual is impaired. Some people may be intoxicated and have BACs that exceed the legal limits yet appear sober. Breathalysers are important because they objectively measure a person’s level of intoxication. Expressed in g/mL or mg/mL, a person’s BAC is affected by a variety of factors including gender, weight, height and the amount of food consumed. A higher BAC indicates that the person has a greater volume of alcohol in his or her system and is more likely to be intoxicated. Many countries around the world have established maximum legal BAC levels permitted for motor vehicle operators. Maximum BAC levels help law enforcement officials enforce against those driving while intoxicated and to prosecute violators.

There are many types of breathalysers. Listed below are the most common types of breathalysers, most of which can be easily purchased.

Passive Breathalysers

• Also called passive alcohol sensors (PAS), passive breathalysers are usually installed on police flashlights or clipboards. Drivers do not actively blow air into a mouthpiece. Rather, the fuel cell sensor inside the breathalyser detects the alcohol in the breath exhaled by the driver. While the results of passive breathalysers are usually not accepted as weighty evidence in the United States, a high BAC establishes probable cause for an officer to investigate the driver more closely. Passive breathalysers are most helpful in reducing the number of undetected intoxicated drivers.

Active Breathalysers

• Active breathalysers require the driver to actively blow into a mouthpiece. Law enforcement officials use a portable, hand-held active breathalyser as part of a Preliminary Breath Test (PBT).
• Professional quality breathalysers use fuel cell sensors.
• Personal breathalysers make use of semiconductor sensors. Used by law enforcement officials, fuel cell breathalysers are more accurate and durable than nonprofessional breathalysers. These breathalysers are also more accurate in the case of those individuals having higher BAC levels.

Crystallisers

• Crystallisers do not take the form of electronic gadgets, but rather make use of chemically coated crystals which react to the presence of alcohol by changing color. The crystallisers are programed to test for different levels of BACs including .02, .04, .05 and .08.

Personal Breathalysers

• Personal breathalysers empower individuals to test their personal BAC levels before they drive. These breathalysers differ from active breathalysers in that they are designed to be used by individuals. Drivers can objectively measure their BAC and make a responsible choice not to drive. Some personal breathalysers take the form of key chains, eliminating any excuses for driving while intoxicated.

Alcohol Ignition Interlock Devices (IID) or Breath Alcohol Ignition Interlock Device (BAIID)

• An IID is a small device installed in the starting circuit of a car. The driver blows into the device and if the driver’s BAC meets or surpasses the level pre-registered into the IID, then the car will not start. If the driver’s BAC is below the measurable level, then the car will start as usual.

Bar-top Breathalysers

• Bar-top breathalysers operate like vending machines for testing BAC. Already used in Australia, New Zealand and the United States, bar-top breathalysers promote a responsible image for businesses and provide a discreet way for customers to test themselves before getting behind the wheel.