Educational exam prep, not medical advice. This page teaches what certification exams test. Follow your facility’s policies, your supervising clinician and the manufacturer’s instructions in practice. If you are a patient with a health question, talk to your clinician or see MedlinePlus.
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Order of draw quiz
Order of draw trainer
Printable order of draw (venipuncture)
| # | Tube | Additive |
|---|---|---|
| 1 | Blood cultures / sterile | Media |
| 2 | Light blue | Sodium citrate |
| 3 | Red / gold SST | Clot activator +/- gel |
| 4 | Green / light green | Heparin |
| 5 | Lavender / pink | EDTA |
| 6 | Gray | Sodium fluoride / potassium oxalate |
Capillary (skin puncture) order
| # | Specimen |
|---|---|
| 1 | Blood gases |
| 2 | EDTA |
| 3 | Other additive tubes |
| 4 | Serum tubes |
Mnemonic
“Be Loving, Respectful, Gentle, Like Grandma” - Blood cultures, Light blue, Red/gold, Green, Lavender, Gray. Why the order: each additive could contaminate the next tube (EDTA raises potassium; clot activator affects coagulation tests).
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CNA, PTCB and CCMA prep course - $19
1,297 original practice questions for CNA, PTCB and CCMA, with explanations, timed exams and domain score reports. One-time $19 for 90 days, emailed to you after purchase - no subscription.
Your course access is emailed to you after purchase. 14-day money-back guarantee. Refund policy
Frequently asked questions
What is the correct order of draw?
Blood cultures/sterile, light blue (citrate), red/gold (serum), green (heparin), lavender (EDTA), gray (fluoride) - the CLSI GP41 convention.
Is the capillary order of draw different?
Yes. After blood gases, EDTA is collected first, then other additives, then serum.
Why does the order of draw matter?
To stop additive carryover between tubes, which can change results (for example EDTA falsely raising potassium).
Sources
- BD - Vacutainer Order of Draw and tube guide (accessed 2026-09-23)
- CLSI GP41 - Collection of Diagnostic Venous Blood Specimens (standard reference) (accessed 2026-09-23)
- NHA - CPT Test Plan (2024 job analysis) (accessed 2026-09-23)