How does a Breath Analyser work?
A Breath Analyser estimates your BrAC (breath alcohol content) by measuring Ethanol’s amount in your breath. The first breath analyser was invented in the early 20th century. They were in regular use by Police from the 1940s. The only other methods for testing for drunkenness at the time were blood or urine tests. These were impossible for police to use out in the field. Breath analyser gave them the system they needed to keep drunk drivers off the road.
How the Body Absorbs Alcohol
When you drink alcohol, the ethanol it contains is absorbed into your body. This is through your mouth, esophagus, stomach, and intestines. Ethanol evaporates easily within the body into your bloodstream due to our internal body temperature. As the blood containing this alcohol passes around your lungs, the ethanol evaporates into them. The ethanol is stored in areas in the lungs called alveoli. This can be picked up in your breath by a breath analyser.
The alcohol in your alveoli is related to a BAC (blood alcohol content) ratio of 2100 to 1. This means that 1 ml of blood has around the same amount of alcohol as 2100 ml of air from your lungs. Breath analyser uses this ratio to measure your BAC.
Passive and Active Breath Analyser
There are two types of breath analysers available today. These are Passive or Active breath analyser. Passive breath analyser does not give a BAC estimate. They show whether alcohol is present in someone’s system. A Passive breath analyser only needs the subject to speak or blow over the device to sample the breath. For example, the subject may be asked to count to ten. These are useful for workplaces that may have a zero-alcohol policy. Any alcohol on the breath will be picked up.
Passive breath analyser can also be useful in situations where many people need to be tested. For example, all staff are tested through Passive breathalyser. Only those that test positive to alcohol are tested with the Active breath analyser. The passive breath analyser is much faster to use; it speeds up this large group process.
Police will also use a Passive breath analyser first to speed up roadside breath tests. If you fail this Passive test, they will put a mouthpiece into the device and do an Active breath test.
Active breath analyser will give an actual estimate of the amount of alcohol in the blood. An Active breath analyser requires the subject to blow into the device through a mouthpiece for a required amount of time. The active breath analyser is much more accurate then Passive. The air analysed by a passive device can be contaminated by fumes, smoke, or dust. An active device sample is less likely to be contaminated because of the mouthpiece.
The active breath analyser is more common for personal breathalyser use. There are three main types:
Semi-conductor Breath Analyser
Semi-conductor Breath analysers are the most economical type. They are also generally more compact. Some can be small keyrings or similar. The ethyl alcohol in the breath generates an electric current. This occurs as it passes through a mix of acetic acid and water. The electric current formed is in proportion to the amount of alcohol in a person’s blood.
Semi-conductor breath analysers are less accurate than other types however. This is because of the influence of other substances that can act like acetic acid. Diabetics and people on a low-carb diet naturally have more of this in their breath, affecting the reading on a semi-conductor breath analyser. They are also less accurate over multiple consecutive readings than fuel cell models.
Nevertheless, if you want a simple reading to show that someone has been drinking then these models are perfect and affordable. If you want accurate results every time, then they will not suit.
Fuel Cell Breath Analysers
Fuel Cell breath analysers include two platinum electrodes. An acidified electrolyte substance surrounds these electrodes. The ethyl alcohol in the breath is oxidised by passing between the electrodes. This oxidization turns it into acetic acid, protons, and electrons. The electrons produce a measurable current. The more oxidized alcohol present, the stronger the current. A microprocessor measures the BAC.
Fuel Cell breath analysers are the most accurate. There are virtually no contamination issues. The acetic acid in the breath of people with diabetes also does not affect them. Fuel Cell models are also accurate over multiple consecutive tests. Consequently, they are more reliable than semi-conductor models. Police breath analysers are always fuel cell models.
Infra-red Spectrophotometer technology
You will be taken back to the Police station for further tests if you fail a roadside breath test. A desktop breath analyser will be used. These employ Infra-red technology. When you breathe into the analyser, a beam of Infra-red radiation will pass through the sample. The device calculates how much ethanol is in 100ml of air by how much of this radiation reaches the other side of the collection chamber. It uses the same ratio of breath alcohol to blood alcohol as other devices, being 2100:1. The device can then work out the amount of alcohol in the blood and show the screen results. These results can be used in Court as evidence.
The Future of the Breath Analyser
Breath Analysers are now a regular feature in many people’s lives. They help keep our roads and workplaces safe and have subsequently saved many lives.
The basic method of breath analysis has not changed much since the first examples. You blow into a device and chemicals within that device react to the alcohol in the breath.
The modern technology now used, however, has made them much more accurate and reliable. They are also more compact and portable. This technology will no doubt keep improving. Consequently, breath analysers will continue to become a bigger feature in our lives.
The Reliable S80
The BACtrack S80 has proven to be easily the most accurate and reliable personal breathalyser on the market. This unit may not be the most compact or the most technologically advanced breath analyser available in Bluetooth/cell phone connectivity. Still, it makes up for this in being uncomplicated and efficient. It simply does what it is designed to do correctly, over and over again.
The S80 is tough, resilient, and clever and is always accurate and reliable. The S80 has trusted the world over by law enforcement and health professionals who rely on quick, accurate results every time. The BACtrack S80 can be relied on as both an entry-level workplace breath analyser and a high-end personal breath analyser. Clever design by BACtrack has allowed one model to cross over two very different markets.