North Carolina regulates portable breath tests (PBTs), sometimes referred to as the “breathalyzer,” through specific administrative rules and statutory provisions. Law enforcement officers regularly rely on alcohol screening devices to assess whether a driver has consumed alcohol and may be part of the “arrest decision” related to probable cause. To better ensure reliable readings, the Department of Health and Human Services (DHHS) requires that approved devices be calibrated and verified for accuracy on a regular basis. Deviation from the rules is problematic at best and can, in some
circumstances, raise doubt about whether a reported BAC reflects the true breath alcohol content.
This article explains how PBTs fit into North Carolina’s regulatory framework and why calibration rules are important. It references 10A NCAC 41B .0503 and related guidelines for monthly checks, breath simulator solutions, and ethanol gas canisters. If you have questions about calibration or how a screening test may apply to your legal matter, give us a call or text the Powers Law Firm at 704-342-4357. You may also email Bill Powers directly at Bill@CarolinaAttorneys.com.
Below is a synopsis of the sections covered in this article. Each entry links to a segment that discusses calibration and how law enforcement officers administer roadside breath tests in North Carolina.
Carolina Criminal Defense & DUI Lawyer Updates

DUI charges or other criminal matters where BAC plays a role, understanding hemolysis, BAC testing, and its implications can help in reviewing the evidence.
inaccurate or misleading BAC when the decedent—who, in criminal cases, may be considered a victim—had alcohol in their system.
the offense may be charged as first-degree murder under what is commonly called the “felony murder rule.” Under this doctrine, a homicide arising from the perpetration or attempted perpetration of such a felony is treated as first-degree murder, even in the absence of premeditation or deliberation.
communications can strengthen or undercut a case when introduced at trial. Yet questions of authenticity—Is the social media content and the source of those materials identifiable?—and relevance—Does it matter to the issues being tried?—are becoming more and more common during trials.
was released to the custody of his parents pending further legal proceedings.
press charges.” In reality, once law enforcement has arrested someone or a warrant, criminal summons, or citation has been issued, the authority to proceed rests with the State—not necessarily the witness or alleged victim.
convicted, the long-term consequences could include a felony conviction record, potential jail or prison time, and issues finding housing or employment in the future.
when we have to take a ferry to get anywhere else.