How does alcohol concentration in breath correlate to blood alcohol concentration?

The correct answer reflects the methodology used by the Intoxilyzer 9000 to estimate blood alcohol concentration (BAC) based on breath alcohol content. The Intoxilyzer 9000 employs a predetermined ratio, known as the partition ratio, which establishes a correlation between the amount of alcohol in a person's breath and the amount of alcohol in their blood. This ratio is based on established scientific principles that account for the physiology of alcohol absorption and distribution within the human body.

Typically, this ratio is approximately 2100:1, meaning that for every 2100 milliliters of breath, there is an equivalent of 1 milliliter of blood that contains the same amount of alcohol. This means that the breath alcohol concentration (BrAC) can be converted to an estimated BAC using this fixed ratio.

The other choices do not accurately capture the relationship between breath and blood alcohol concentrations. A direct one-to-one relationship does not hold true, as the ratios are not equal due to physiological differences. Saying no correlation exists fundamentally misrepresents the scientific basis of breath testing, which directly relies on these established ratios. Additionally, the notion that breath concentration is always higher is not correct; the conversion is based on the predetermined ratio rather than a consistent