Friday, August 2, 2013

Fundamentals About A Breathalyzer Machine

By Cathy Mercer


A breathalyzer machine refers to a device used to estimate the content of alcohol in the blood using a breath sample. The invention of this device dates as back as 1874. Back then, there were only observations of the possibility of detecting the presence of alcohol in the blood stream using breath. The observations were built onto until the device was first invented by a chemist in Chicago in 1927.

The Chicago chemist however cannot be said to be the inventor of the device because there were earlier experiments about the same. Currently there are many versions of this equipment although the mode of operation remains the same across all of them. The person being tested is required to exhale into the breath analyzer. The equipment has an anode and a cathode terminal.

Any amount of ethanol existing in the breath gets oxidized to produce acetic acid at the anode lead. At the cathode lead, atmospheric oxygen available in the breath gets reduced. The general reaction, which occurs in the entire activity is the oxidation of available ethanol into acetic acid and water. The reaction produces an electric current, which is then measured by some microprocessor in the device.

The reading of produced electric current is indicated as an approximation of (BAC) blood alcohol content by the alcosensors. The displayed value gets represented in terms of quantity of alcohol percentage per given air volume. The correctness of contemporary devices is very reliable and high. Chromium trioxide is the most used oxidizing agent in most gadgets.

There are two main technologies or versions of breath analyzers in the market presently. The first version is known as the desktop analyzer, which in general uses electro-chemical fuel cell or infrared spectro-photometer technology or a combination of the two. Hand-held versions of this gadget are produced basing on electrochemical fuel cell technology.

Breatherlyser machines are used in many fields on a private or public scale. Law enforcement officers in many states use the device on highways to catch up with people who drive under the influence of alcohol. The device provides a non-invasive way of determining if one has alcohol in their body. The outcome of the test is presented in court as evidence against people who break the law about driving under influence. One is only arrested when the specified level of alcohol content in blood is exceeded.

The price for a breathaliser equipment depends on its make and quality. The models used by law enforcement officers are very expensive because they use expensive technology. The price however matches their high level of sensitivity, reliability, and accuracy. There are devices that are used by individuals and companies too. These ones mainly use semiconductor based technology, which is less reliable, less accurate, and cheap.

The devices are standardized and certified by different bodies in different countries. For instance in the US, the Food and Drug Administration authority is responsible for ensuring quality of the machines sold to members of the public. A breathalyzer machine being sold in the market does not mean that it is as accurate. For this reason, test results from gadgets that are based on semi-conductor technology are not used in courts as evidence.




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