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Gas Chromatography Mass Spectrometry (An Overview)

Dayton DUI Attorney Charles Rowland > DUI Law  > DUI Process  > Gas Chromatography Mass Spectrometry (An Overview)

Gas Chromatography Mass Spectrometry (An Overview)

gcms wikipediaTo fully comprehend the processes of chemical testing, your DUI attorney should understand gas chromatography – mass spectrometry. Gas chromatography mass spectrometry (hereinafter GCMS)  is a method that combines the features of gas-liquid chromatography and mass spectrometry to identify different substances within a test sample.  GC-MS has been widely heralded as a “gold standard” for forensic substance identification because it is used to perform a specific test.

Ohio Administrative Code 3701-53-03(A) sets forth the techniques and methods for determining the concentration of alcohol in blood, urine and other bodily substances.  Pursuant to that rule, Ohio allows for testing including gas chromatography and enzyme assays.  The GCMS instrument is made up of two parts. The gas chromatography (GC) portion separates the chemical mixture into pulses of pure chemicals and the mass spectrometer (MS) identifies and quantifies the chemicals.  The GC separates chemicals based on their volatility, or ease with which they evaporate into a gas. It is similar to a running race where a group of people begin at the starting line, but as the race proceeds, the runners separate based on their speed. The chemicals in the mixture separate based on their volatility. In general, small molecules travel more quickly than larger molecules.  The MS is used to identify chemicals based on their structure.

In order to successfully defend a blood test case, a DUI defense lawyer must be familiar with Ohio’s DUI law (O.R.C. 4511.19) and the Ohio Administrative Code sections which apply to the collection, storing, transporting and testing of the whole blood, blood plasma and/or blood serum specimen.  Amphetamine, cocaine, heroine, Marijuana, Methamphetamine, Phencyclidine and L.S.D. are specifically mentioned in Ohio’s DUI/OVI statute as illegal controlled substances. The law states how much of each substance must be detected in a chemical test of urine, whole blood, blood plasma, and/or blood serum in order to sustain a charge.  A blood test is seen as the most accurate and reliable method of testing but is the most invasive.  The blood test is increasingly favored by law enforcement officers because it allows them to expand the parameters of their suspicion to include illicit and prescription drugs. Sometimes the blood test will be requested after a breath test produces a result under the .08% BAC limit.  If this is the case, your attorney should employ more traditional factual defenses such as a lack of probable cause to suspect drug use before leaping to a more scientific challenge to the collection, storage, transporting or testing of the blood sample.  If the facts support a blood test then your attorney must hold the State to its proof.

Charles M. Rowland II, DaytonDUI, is a member of the National College for DUI Defense and has attended the National Mastering Scientific Evidence seminar on multiple occasions.  He is the only attorney in Ohio to hold a certificate in Forensic Sobriety Assessment.  His commitment to understanding and winning through the use of science has made him the Miami Valley’s choice for DUI Defense. For the last seven years, Charles has focused exclusively on the complex field of DUI defense. Charles has spoken and written about DUI and is the only attorney in Ohio to hold a Forensic Sobriety Assessment certification.  Don’t you want an attorney who will defend you with the same “by any means necessary” mentality that Ohio has adopted with which to secure your conviction?  I dedicate my practice to defending the accused drunk driver in the following jurisdictions: FairbornDaytonSpringfieldKetteringVandaliaXeniaMiamisburgSpringboro,Huber HeightsOakwoodBeavercreekCenterville and throughout Ohio.  He has the credentials and the experience to win your case and has made himself the Miami Valley’s choice for DUI defense.  Contact me by phone at 937-318-1DUI (937-318-1384), 937-879-9542, or toll-free at 1-888-ROWLAND (888-769-5263).  For after-hours help contact our 24/7 DUI HOTLINE at 937-776-2671.  For information about Dayton DUI sent directly to your mobile device, text DaytonDUI (one word) to 50500.  Follow DaytonDUI on Twitter @DaytonDUI or Get Twitter updates via SMS by texting DaytonDUI to40404. DaytonDUI is also available on Facebook and on the DaytonDUI channel on YouTube.  You can also email me at: CharlesRowland@DaytonDUI.com or write to us at 2190 Gateway Dr., Fairborn, Ohio 45324. “All I do is DUI

Charles Rowland


Charles M. Rowland II has been representing the accused drunk driver for over 20 years. Contact him at (937) 318-1384 if you find yourself facing a DUI (now called OVI) charge.

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