Training Pillar · Phlebotomy
Phlebotomy Certification Prep & Order of Draw Training
Practice the CLSI order of draw with an interactive tube simulator, then test yourself with NHA CPT-style practice questions covering patient ID, site selection, additives, and complications — each with a rationale.
Order of Draw Simulator
Tap the tubes in the correct CLSI order of draw for a multi-tube venipuncture.
| # | Tube | Additive | Common tests |
|---|---|---|---|
| 1 | Blood culture bottles | Broth (SPS) | Microbiology — sepsis workup |
| 2 | Light blue | Sodium citrate | Coagulation (PT/INR, aPTT) |
| 3 | Red / Gold (SST) | Clot activator ± gel | Chemistry, serology (serum) |
| 4 | Green | Lithium / sodium heparin | STAT chemistry (plasma) |
| 5 | Lavender | K2EDTA | CBC, HbA1c, blood bank |
| 6 | Gray | Sodium fluoride / K oxalate | Glucose, lactate, alcohol |
NHA CPT-Style Practice Questions
Question 1 of 10
Which tube is drawn immediately after blood culture bottles in the CLSI order of draw?
Go Deeper
Study phlebotomy with a preceptor
Ready to go further? Mara Solis, a fictional digital instructor, guides the Phlebotomy & Pre-Analytical Science room. Study tube additives, safe collection and specimen handling with a dedicated board and question chat.
Open the phlebotomy study room →Included with beta access — you'll be asked to sign in first.
Labnology practice content is original and independent; it is not affiliated with, endorsed by, or a copy of the National Healthcareer Association (NHA) CPT exam. Always follow your facility's procedures.