Ever wondered how DPS operates their DWI blood testing machine? Probably not. But if you are a DWI attorney, or defendant, this is an important topic.
I am proud to present the Texas Department of Public Safety’s
Standard Operating Procedures for Blood Alcohol Analysis by Gas Chromatography
Interesting fact about Gas Chromatography machines. GC machines do NOT measure the amount of alcohol in a blood sample. Rather a GC measures the chemicals in the head space gas surrounding the sample. Henry’s Law is applied to determine what the BAC is.
The manual is short, but not a very exiting read. If any scientists/medical technicians wish to offer some insight please comment.