NHA Phlebotomy Practice Test Questions With
Accurate Answers (2026) | Latest 2026 | Digital
Pdf Download
elow is a comprehensive collection of NHA Phlebotomy Technician (CPT) practice
B
questions with verified correct answers and detailed rationales. These questions cover
the major content areas of the national exam: Safety & Compliance, Patient
Preparation, Routine Blood Collection, Special Collections, and Processing .
SECTION 1: Order of Draw & Additives
Question 1
A phlebotomist must collect a light blue top tube, a lavender top tube, and
a green top tube. After cleaning the site with an alcohol pad, what is the
correct order of draw?
A) Lavender, green, light blue
B) Green, lavender, light blue
C) Light blue, green, lavender
D) Green, light blue, lavender
Correct Answer: C – Light blue, green, lavender
© 2026 Academics_Excellence Stuvia
,Rationale: The correct order of draw prevents additive carryover. Light
blue tubes (sodium citrate) are drawn first among non-culture tubes to
avoid contamination with other additives. Green (heparin) is drawn before
lavender (EDTA) to prevent EDTA from falsely lowering calcium and
affecting coagulation test results .
Question 2
Which additive is contained in a light blue top tube?
A) EDTA
B) Sodium citrate
C) Lithium heparin
D) Sodium fluoride
Correct Answer: B – Sodium citrate
Rationale: Light blue top tubes contain sodium citrate, which binds
calcium to prevent blood from clotting. These tubes are used for
coagulation studies such as PT/INR and PTT. The proper blood-to-additive
ratio (9:1) is critical .
© 2026 Academics_Excellence Stuvia
,Question 3
A phlebotomist needs to collect a CBC and a basic metabolic panel (BMP).
Which tubes should be used and in what order?
A) Lavender then green
B) Green then lavender
C) Lavender then SST (gold/red)
D) SST then lavender
Correct Answer: A – Lavender then green
Rationale: The CBC requires a lavender top tube (EDTA). The BMP can be
collected in a green top (heparin) or SST (serum separator). According to
the order of draw, lavender (EDTA) is drawn before green (heparin) to
prevent heparin contamination .
Question 4
A phlebotomist must collect a prothrombin time (PT/INR) and a complete
blood count (CBC). Which is the correct order of draw?
A) Lavender, light blue
B) Light blue, lavender
C) Green, lavender
D) Lavender, green
© 2026 Academics_Excellence Stuvia
, Correct Answer: B – Light blue, lavender
Rationale: Light blue tubes (sodium citrate) must be drawn before lavender
tubes (EDTA) to prevent EDTA contamination, which would cause falsely
prolonged clotting times. This order preserves the accuracy of coagulation
test results .
Question 5
Which tube additive prevents glycolysis (breakdown of glucose) in a blood
specimen?
A) EDTA
B) Sodium polyanethol sulfonate (SPS)
C) Sodium fluoride
D) Lithium heparin
Correct Answer: C – Sodium fluoride
Rationale: Sodium fluoride is a glycolytic inhibitor that preserves glucose
levels in blood specimens. Gray top tubes contain sodium fluoride and are
used for glucose testing, lactate testing, and sometimes alcohol levels. The
additive prevents red blood cells from consuming glucose after collection .
© 2026 Academics_Excellence Stuvia
Accurate Answers (2026) | Latest 2026 | Digital
Pdf Download
elow is a comprehensive collection of NHA Phlebotomy Technician (CPT) practice
B
questions with verified correct answers and detailed rationales. These questions cover
the major content areas of the national exam: Safety & Compliance, Patient
Preparation, Routine Blood Collection, Special Collections, and Processing .
SECTION 1: Order of Draw & Additives
Question 1
A phlebotomist must collect a light blue top tube, a lavender top tube, and
a green top tube. After cleaning the site with an alcohol pad, what is the
correct order of draw?
A) Lavender, green, light blue
B) Green, lavender, light blue
C) Light blue, green, lavender
D) Green, light blue, lavender
Correct Answer: C – Light blue, green, lavender
© 2026 Academics_Excellence Stuvia
,Rationale: The correct order of draw prevents additive carryover. Light
blue tubes (sodium citrate) are drawn first among non-culture tubes to
avoid contamination with other additives. Green (heparin) is drawn before
lavender (EDTA) to prevent EDTA from falsely lowering calcium and
affecting coagulation test results .
Question 2
Which additive is contained in a light blue top tube?
A) EDTA
B) Sodium citrate
C) Lithium heparin
D) Sodium fluoride
Correct Answer: B – Sodium citrate
Rationale: Light blue top tubes contain sodium citrate, which binds
calcium to prevent blood from clotting. These tubes are used for
coagulation studies such as PT/INR and PTT. The proper blood-to-additive
ratio (9:1) is critical .
© 2026 Academics_Excellence Stuvia
,Question 3
A phlebotomist needs to collect a CBC and a basic metabolic panel (BMP).
Which tubes should be used and in what order?
A) Lavender then green
B) Green then lavender
C) Lavender then SST (gold/red)
D) SST then lavender
Correct Answer: A – Lavender then green
Rationale: The CBC requires a lavender top tube (EDTA). The BMP can be
collected in a green top (heparin) or SST (serum separator). According to
the order of draw, lavender (EDTA) is drawn before green (heparin) to
prevent heparin contamination .
Question 4
A phlebotomist must collect a prothrombin time (PT/INR) and a complete
blood count (CBC). Which is the correct order of draw?
A) Lavender, light blue
B) Light blue, lavender
C) Green, lavender
D) Lavender, green
© 2026 Academics_Excellence Stuvia
, Correct Answer: B – Light blue, lavender
Rationale: Light blue tubes (sodium citrate) must be drawn before lavender
tubes (EDTA) to prevent EDTA contamination, which would cause falsely
prolonged clotting times. This order preserves the accuracy of coagulation
test results .
Question 5
Which tube additive prevents glycolysis (breakdown of glucose) in a blood
specimen?
A) EDTA
B) Sodium polyanethol sulfonate (SPS)
C) Sodium fluoride
D) Lithium heparin
Correct Answer: C – Sodium fluoride
Rationale: Sodium fluoride is a glycolytic inhibitor that preserves glucose
levels in blood specimens. Gray top tubes contain sodium fluoride and are
used for glucose testing, lactate testing, and sometimes alcohol levels. The
additive prevents red blood cells from consuming glucose after collection .
© 2026 Academics_Excellence Stuvia
