Core Requirements for Blood Collection and Securing Samples

1. Collection Personnel and Technique

• Blood must be drawn by authorized personnel (e.g., licensed physician, registered nurse, certified phlebotomist, or other qualified individual per state law). A trained phlebotomist, as in the scenario, is generally acceptable.
• Use aseptic technique with a non-alcohol-based antiseptic (e.g., povidone-iodine/Betadine, aqueous benzalkonium chloride, or similar) and let sit for 2 minutes before drawing blood to allow the antiseptic to do its work. Alcohol swabs are avoided to prevent potential extraneous alcohol contamination.
• Recommended: Gray-top vacuum tubes containing sodium fluoride (NaF, preservative/inhibitor of microbial activity and glycolysis, typically 1–2%) and potassium oxalate (anticoagulant, ~0.2%). These prevent clotting and in vitro ethanol production/fermentation.
• Tubes must be filled until the vacuum is exhausted which occurs when the blood reaches its stated capacity. Otherwise, the tubes will be prone to taking bacteria and yeast which can alter the blood alcohol content
• You have to disconnect the tube from the needle before the needle is removed from the air or ambient air will be drawn into the blood tube. 

Recommended minimum: Often 2 × 10 mL tubes for forensic purposes (allows for retesting or defense analysis).

Immediately after draw: Invert the tube(s) a minimum of 8 times (or per manufacturer/lab protocol) to mix additives thoroughly.

2. Labeling (Critical for Identification)

• Label each individual vial/tube immediately after collection (ideally at the subject's side or in their presence).
• Required information typically includes: subject’s full name, date/time of collection, collector’s name/initials, witnessing officer’s initials, case number or identifier, and sometimes location or specimen type.
• The phlebotomist/collector usually completes and initials the label first; the officer then initials it.

3. Sealing and Packaging

• Individual tubes/vials are often secured with tamper-evident seals or tape (initialed).
• Tubes are then placed into a tamper-evident evidence envelope, bag, or approved collection kit.
• The outer packaging (envelope/kit) must be properly sealed (e.g., with evidence tape across seams, initialed/date by the officer). Once sealed, it should not be reopened except by the laboratory.
• Use protective packaging to prevent breakage/leakage and limit headspace where possible. Many jurisdictions provide standardized DUI blood kits with pre-printed forms, security seals, and instructions.

4. Chain of Custody

• Continuous documentation from the moment of collection through transport, storage, and analysis.
• Every person handling the sample signs/logs: name, date, time, and action.
• The outer sealed container and forms typically include fields for this. Gaps or incomplete documentation can undermine admissibility or weight of the evidence.

5. Storage and Transport

• Typically refrigerated (around 2–8°C / ~8°C or roughly 35°F / ~45°F  recommended in best practices) unless lab instructions differ.
• Timely transport to an accredited forensic laboratory.
• Proper preservatives (NaF) help maintain stability, and BAC results are generally reliable even after weeks/months if handled correctly — but poor initial securing increases challenges.

6. Laboratory Side

• Labs must use validated methods (commonly headspace gas chromatography), quality controls, uncertainty measurements, and follow accreditation standards.
• Additional national standards exist for analytical scope/sensitivity in impaired driving cases (e.g., ANSI/ASB Standard 120).

Deviations from these practices (wrong tubes, no preservatives, poor mixing, inadequate labeling/sealing, or chain-of-custody gaps) can lead to challenges regarding sample integrity, potential contamination/tampering, or misidentification.

Critical Steps: Labeling, Sealing, and Chain of Custody

This is where many cases go wrong — and where strong defenses are built.

Proper procedure typically requires:

1. The phlebotomist labels each vial immediately after the draw with the subject’s name, date/time of collection, collector’s name/initials, and other identifying information.
2. The officer or collector initials the labels.
3. Vials are placed in a tamper-evident inner bag or holder.
4. The outer evidence kit/envelope or box is then sealed with security seals (often red “integrity seals” that must be initialed and dated).
5. Every person who handles the sealed kit documents the transfer on the chain-of-custody form.

Why this matters: The chain of custody proves the blood tested at the GBI lab is the same blood drawn from you and that it was not tampered with, contaminated, or misidentified.

Common Errors That Can Weaken or Exclude Blood Test Results

In many Georgia DUI cases we review, officers or collectors fail to follow these steps properly. Examples include:

• Failing to label the individual vials before placing them in the evidence envelope.
• Not sealing the vials or the outer kit properly.
• Gaps in chain-of-custody documentation.
• Improper storage or transport (Police often mails samples during the heat of summer for ten days or more in the U.S. Mail ; temperature fluctuations can affect results).
• Using expired tubes or incorrect preservatives.
• Homemade labels that cover manufacturer information on the tubes (including expiration dates and preservative details).

When these errors occur, the scientific reliability of the BAC result can be challenged. Fermentation inside the tube (if preservatives weren’t properly mixed or the sample wasn’t stored correctly) can artificially increase the reported alcohol level after collection. Courts require the State to lay a proper foundation before admitting the results.

How an Experienced DUI Attorney Uses These Standards

A skilled Atlanta DUI lawyer will obtain the full discovery — including the blood kit documentation, chain-of-custody logs, GBI lab reports, and any bodycam or dashcam footage of the draw. We look for exactly the kinds of procedural mistakes described above.

When we find violations of forensic standards or Georgia law, we can file motions to:

• Suppress the blood test results entirely.
• Limit the weight the jury can give the evidence.
• Create reasonable doubt about the accuracy of the reported BAC.

Many of our clients have seen charges reduced or dismissed because the State could not prove the blood sample was properly collected and secured.