Comments on: How Do You Know the Blood They Tested was Yours? http://www.duiblog.com/2006/03/31/how-do-you-know-the-blood-they-tested-was-yours/ Bad Drunk Driving Laws, False Evidence and a Fading Constitution Wed, 19 Jun 2013 13:34:34 +0000 hourly 1 http://wordpress.org/?v=3.4.2 By: Tox Lab Guy http://www.duiblog.com/2006/03/31/how-do-you-know-the-blood-they-tested-was-yours/comment-page-1/#comment-59 Tox Lab Guy Sat, 01 Apr 2006 03:31:11 +0000 http://duiblog.level2hosting.com/?p=323#comment-59 <a></a>Our laboratory employs a procedure of running an aqueous alcohol "blank" between each of our intox assault cases. This simple process has two very important benefits: It minimizes the possibility of "carryover" or the contamination of a sample by the previous one It provides a mental key change in the process of consecutive sample preparations, preventing the chemist from moving directly from one case to another Another "break" in the process of preparing sequential samples is the inclusion of a control at every 10th position (a trend started by California laboratories). Some other techniques that are beneficial to prevent the whole sample mix-up nightmare include always analyzing cases in ascending numerical order, only opening one envelope at a time, and doing a visual matchup of vial label to position on the GC sequence list. Small things, yes, but their cumulative effect among non-clueless crime lab personnel minimizes mix-up potential. Our laboratory employs a procedure of running an aqueous alcohol “blank” between each of our intox assault cases. This simple process has two very important benefits:

It minimizes the possibility of “carryover” or the contamination of a sample by the previous one
It provides a mental key change in the process of consecutive sample preparations, preventing the chemist from moving directly from one case to another
Another “break” in the process of preparing sequential samples is the inclusion of a control at every 10th position (a trend started by California laboratories). Some other techniques that are beneficial to prevent the whole sample mix-up nightmare include always analyzing cases in ascending numerical order, only opening one envelope at a time, and doing a visual matchup of vial label to position on the GC sequence list. Small things, yes, but their cumulative effect among non-clueless crime lab personnel minimizes mix-up potential.

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