Specimen Collection Guides

Complete reference for phlebotomy procedures, tube types, order of draw, and collection best practices.

Quick Tube Lookup

Search by tube color, test name, or specimen type

Tube Reference Chart

Tube Name	Additive	Inversions	Specimen	Common Tests
Red	None (glass) / Clot activator (plastic)	0× (glass) / 5× (plastic)	Serum	Serology, blood bank, therapeutic drug monitoring, some chemistry
Gold / Red-Gray (SST)	Serum separator gel + Clot activator	5×	Serum	Chemistry panels (CMP, BMP), lipid panels, hormone tests, iron studies, cardiac markers
Light Blue	Sodium Citrate (3.2%)	3–4×	Plasma	PT/INR, aPTT, D-dimer, fibrinogen, coagulation studies
Green / Green-Gray (PST)	Lithium or Sodium Heparin	8×	Plasma	STAT chemistry, ammonia, troponin, cardiac markers, ionized calcium
Lavender / Purple	EDTA (K2 or K3)	8×	Whole Blood	CBC with differential, ESR, HbA1c, blood typing, flow cytometry
Yellow (ACD)	Acid Citrate Dextrose	8×	Whole Blood	HLA typing, paternity testing, platelet function, tissue typing
Gray	Sodium Fluoride / Potassium Oxalate	8×	Plasma	Fasting glucose, lactate, blood alcohol, GTT specimens
Dark Blue (Royal Blue)	None (trace-element free) or EDTA	8×	Whole Blood / Plasma	Trace metals (lead, copper, zinc), toxicology, selenium
Tan / Brown	Sodium Heparin (lead-free)	8×	Plasma	Lead testing only

Order of Draw

Following the correct order of draw prevents cross-contamination between tube additives. Always follow this sequence for every patient encounter.

Blood Culture Bottles

Sterilized first to avoid contamination

Light Blue (Sodium Citrate)

Must be filled completely; ratio critical

Red (No Additive) / Gold SST

Serum tubes — no additive interference from anticoagulants

Green / Green-Gray (PST)

Heparin tubes after serum tubes

Lavender / Purple (EDTA)

EDTA after heparin to prevent cross-contamination

Gray (Fluoride / Oxalate)

Glycolytic inhibitor; drawn last of routine tubes

Collection Procedures

Collection Best Practices

Patient Identification

Always use two identifiers: full name and date of birth. Never draw from an unidentified patient. Mismatched labels are the #1 cause of rejected specimens.

Hemolysis Prevention

Allow alcohol to dry completely. Use the correct needle gauge (21–23g for adults). Never force blood through a needle into a tube. Invert tubes gently — do not shake.

Timing Requirements

Tourniquet time must not exceed 1 minute. Release tourniquet as soon as blood flows. Prolonged stasis causes hemoconcentration and falsely elevates protein, potassium, and calcium values.

Temperature & Transport

Some tests require special handling: ABGs on ice, cryoglobulins at 37°C, cold agglutinins pre-warmed. Transport routine specimens to lab within 45 minutes of collection.