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While breath testing is part of every DUI arrest, most don’t know what to expect. As a result, we explain proper breath testing guidelines.

Proper Breath Testing Procedure

Because a BAC level is important to the State, proper breath testing procedure is also important to us. While we question any BAC reading, not following manufacturer’s testing guidelines can suppress the result. Here in South Carolina, we use the DataMaster DMT machine manufactured by National Patent Analytical Systems, Inc. And like most breathalyzers, it is a box containing a computer motherboard and a printer. During testing, breath somehow turns into a number. Just how it becomes a number is something of a mystery that no one can fully explain. But here is what we do know.

In order to get a valid sample, the manufacturer’s manual directs a steady blow of air. In addition, the manual states to not “blow hard.” However, that guideline has changed as being “not helpful.” So what is the proper breath testing procedure now? Rather than guess, we still go with the slow, steady blow. After all, it’s just common sense that forcing additional air under pressure will change the outcome. Furthermore, we are already dealing with very small numbers (0.01). Therefore, any significant change in input could affect output. And that can create reasonable doubt as to the result.

BAC Reading or Video Evidence

Because we trust our own eyes and ears over any machine, we rely on video evidence. In addition, we see too many cases where the client’s behavior on video does not match a high BAC. Rather than just argue the machine, we also focus on how someone looks and sounds. Hence everyone knows how people act when “drunk” or “impaired.” So at trial, we create reasonable doubt when the BAC and video conduct are different. And that’s how juries decide guilt or innocence. Call now and let’s start your defense today. You’re going to feel better after we talk.