A driver convicted of driving under the influence more than once may have to have an ignition interlock device installed on his or her vehicle. The IID provides limited freedom to drive from place to place but prevents a person from operating a motor vehicle if it detects any alcohol on a person’s breath.
There are facts that authorities or manufacturers may not disclose about the devices before people have them installed. People who must have an ignition interlock device in their cars, or who choose to have one, should be aware of a couple of important facts.
The threshold is low
In most states, including Georgia, the legal limit for blood alcohol concentration is 0.08%. If a driver’s BAC is at or above this level, the law presumes that he or she is too drunk to drive. However, according to the National Conference of State Legislatures, an ignition interlock device can prevent a driver from operating the vehicle with a BAC of much less than 0.08%.
False positives are possible
An ignition interlock device may misinterpret things like cigarette smoke, perfume or hand sanitizer and give a false-positive result even when a person has not been drinking. According to Men’s Health, certain medical conditions can also put a driver at risk for a false positive, such as acid reflux disease.
Ketosis is a condition that causes the liver to produce alcohol as a byproduct of breaking down fats for energy. It is common in diabetics and people who eat a low-carb diet for weight loss. Ketosis may interfere with breath tests, causing them to yield inaccurate results.