Breathalyzers must be correctly administered and calibrated in order to get even a rough reading of a person’s blood alcohol content. Although they are sold commercially, the most common usage of these devices is by officers who pull over drivers they suspect to be under the influence. The machine reads the blood alcohol content (BAC) of breath, not the blood. If it reads a high amount, the office may arrest an individual and accuse him or her of the crime.
The technology behind breathalyzers is not an exact science. The devices are subject to quite a bit of variation. Officers should be aware of the ways this device may falsely represent a BAC. The temperature both inside and outside can affect a result.
Another common way these devices fail to provide a correct reading is because they are affected by the breathing pattern of the subject. For many people, it is hard to calm down after being pulled over for a suspected DUI. The heart rate may climb and affect the breathing pattern of an individual. Since breathalyzers rely on the alcohol content of the actual breath, the device may have a hard time delivering an accurate reading. Cell volume of blood differs among individuals and can also affect a reading. Contamination of the device may also change a reading.
Many companies now offer products that allow drivers to check blood alcohol content before getting behind the wheel. It is sometimes very difficult to judge someone’s own blood alcohol level and therefore these small, inexpensive devices may aid in the event of a DUI suspicion.