The State Isn't Calibrating Its Breath Machines Properly

Posted On August 08, 2023 Charles Ramsay

This blog continues to be the #1 place where you can find scientific problems related to the state’s drug and alcohol testing. Every week we’re uncovering more problems with the state's testing lab, and this week is no exception.

To give a quick recap, we’ve pointed out how the state failed to properly make its acetone solution used to check for interfering substances on the DMT; how the state improperly disabled the fuel cell; and how normal substances on your breath can put you over the legal limit.

The state takes shortcuts when calibrating the breath alcohol machine

The state has taken so many shortcuts in chemical testing that it is a full-time job to keep up with all its problems. And it is no surprise that they use shortcuts when it comes to the most important part of breath alcohol testing: the machine's calibration.

The state used to calibrate their machines with breath alcohol simulators. These are mason jars filled with solutions of water and alcohol that are made to mimic human breath. But around 2017, the state decided to stop using the wet-bath solutions and decided to calibrate with dry gas instead.

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It’s more convenient to calibrate with dry gas. The state doesn’t have to deal with making solutions (which they don’t do well) and bringing solutions to the proper temperature.

Wet-bath calibration unit. Photo credit: SGBreathalyzers

It’s easier for the state to use dry gas, but the citizens of Minnesota suffer.

In science, it’s common knowledge that you should calibrate your machine with the same matrix (blood, breath, or urine) that you want to measure. The state is using a foreign compound to calibrate its machines.

The most published breath alcohol scientist in history, AW Jones, said that wet-bath simulators are essential and shouldn’t be abandoned.

“…the primary mode of calibrating breath-alcohol analyzers should still entail the use of wet-bath simulators so that the gas standard has the same composition as the biological specimen (breath) intended to be measured, that is, alcohol-in-air saturated with water vapor.” - AW Jones

Convenience ≠ better

Without matrix-matched controls, we can’t know if the machine is measuring breath accurately. Dry gas is missing one critical component: water. Human breath contains water, and it absorbs infrared in the same light spectrum as alcohol. 

Without proper calibration, citizens of Minnesota have no way of knowing if the state’s breath machine is measuring properly.

Call a lawyer who knows the science — call Ramsay Law

At Ramsay Law, we dig deep into the science to get you unprecedented results. We’re not just lawyers; we’re lawyer-scientists. Call us if you’ve been a victim of the state’s improper calibration — we get results.

Daniel Koewler