Which type of alcohol is specifically referenced in the context of intoxilyzer testing?

The type of alcohol specifically referenced in the context of intoxilyzer testing is ethyl alcohol, also known as ethanol. Ethanol is the form of alcohol that is consumed in beverages and is the substance that intoxilyzer devices are designed to measure. The Intoxilyzer 9000 uses infrared spectroscopy or other methods to accurately identify and quantify the concentration of ethyl alcohol in breath samples, which is crucial for determining blood alcohol concentration (BAC) in individuals suspected of driving under the influence.

The other types of alcohol listed do not play a role in standard intoxilyzer testing for DUI cases. Butanol, methanol, and isopropyl alcohol may be present in other contexts but are not relevant to alcohol consumption or the legal limits for driving under the influence. Thus, the focus on ethyl alcohol establishes its significance in breath alcohol testing and its direct correlation with the effects of alcohol consumption on the body.