CCHT Technical Practice Test 2026 - Questions and Answers

Last Updated on May 13, 2026

The Nephrology Nursing Certification Commission (NNCC) Certified Clinical Hemodialysis Technician (CCHT) Technical Practice Test 2025 – Questions and Answers Quiz. In the actual test, this part consists of 32 to 38 multiple-choice questions, which is approximately 21–25%.

Questions in this area concern the principles of water treatment, components of the extracorporeal circuit, and actions to take when alarms sound or machine-related problems arise. The Technical area is the second-largest part of the test, accounting for 23% of the test content. Examples of the kinds of technician activities tested in the Technical area include:

1. Participating in monitoring the water treatment system.
2. Checking the conductivity and pH of the dialysate solution with an independent device.
3. Mixing concentrates from powder (bicarbonate, electrolyte solution).
4. Processing patients’ laboratory samples.
5. Identifying/reporting/documenting an adverse event, e.g., equipment set-up problems.

CCHT Technical Practice Test

Technical

1 / 50

1) The venous-line ultrasonic sensor is designed to detect

A) pH changes in blood

B) dialysate temperature

C) air bubbles before blood returns to the patient

D) conductivity spikes in dialysate

2 / 50

2) A persistent high venous pressure alarm usually indicates

A) clotting in the venous line or dialyzer

B) kink in arterial line

C) machine in bypass

D) temperature out of range

3 / 50

3) Heat disinfection of dialysis machines is commonly performed

A) only if bicarbonate is reused

B) once every 30 days

C) only after a positive water culture

D) at the end of each workday

4 / 50

4) A dialysate temperature alarm will place the machine into

A) heat-disinfection mode

B) sodium-profile mode

C) bleaching cycle

D) bypass and stop ultrafiltration

5 / 50

5) Pre-dialysis potassium samples are drawn from the

A) arterial bloodline sampling port before the pump

B) dialysate drain hose

C) patient’s fingerstick

D) venous drip chamber

6 / 50

6) RO membranes are chemically cleaned when product-water flow drops by about

A) cleaning is never done; membranes are discarded

B) 50 % from baseline

C) 2 % from baseline

D) 10 % from baseline

7 / 50

7) Maintaining loop velocity at ≥ 3 ft / sec helps

A) soften feed water

B) prevent bacterial biofilm growth

C) increase residual chlorine

D) lower dialysate pH

8 / 50

8) The AAMI action level for endotoxin in product water is

A) 5.0 EU/mL

B) 10 EU/mL

C) 0.25 EU/mL

D) 1.0 EU/mL

9 / 50

9) A positive blood-leak strip changes color from white to

A) purple

B) red

C) green or blue (per manufacturer)

D) yellow

10 / 50

10) The arterial pressure monitor is located

A) between the patient access and the blood pump

B) after the air detector

C) on the venous drip chamber

D) in the dialysate effluent line

11 / 50

11) Proper blood pump occlusion is verified using a

A) hardness test kit

B) drip test or occlusion gauge

C) pH meter

D) glucose test strip

12 / 50

12) At power-up, a dialysis machine self-test includes

A) calibrating the blood-pressure cuff

B) culturing dialysate for bacteria

C) verifying all alarm functions operate correctly

D) cleaning the bicarbonate jug

13 / 50

13) The proportioning system on a dialysis machine

A) drives the arterial blood pump

B) measures venous air bubbles

C) mixes acid, bicarbonate, and water in fixed ratios

D) sterilizes the extracorporeal circuit

14 / 50

14) Acceptable dialysate pH prior to patient connection is

A) 6.9 – 7.6

B) 7.9 – 8.4

C) 4.0 – 5.0

D) 5.5 – 6.0

15 / 50

15) First action when a blood-leak alarm sounds is to

A) administer 100 mL saline bolus

B) stop the blood pump and verify with a test strip

C) silence the alarm and resume treatment

D) increase dialysate flow to clear the sensor

16 / 50

16) A simultaneous low venous pressure alarm and bleeding at the needle site most likely indicate

A) dialysate too cool

B) high conductance in bath

C) kink in arterial tubing

D) venous needle dislodgement

17 / 50

17) The usual order of water-treatment components is

A) softener → multimedia filter → RO → carbon

B) multimedia filter → softener → carbon → particulate filter → RO → UV → ultrafilter

C) RO → carbon → softener → ultrafilter

D) UV → ultrafilter → multimedia → RO

18 / 50

18) The primary purpose of a reverse osmosis (RO) unit in the dialysis water-treatment system is to

A) soften incoming feed water

B) add electrolytes for taste correction

C) raise total dissolved solids (TDS)

D) remove dissolved salts and microorganisms

19 / 50

19) A dialysis machine goes into bypass when dialysate conductivity is

A) over 0.25 EU/mL endotoxin

B) under 30 °C

C) below 6.0 pH

D) outside ± 0.4 mS/cm of the set point

20 / 50

20) Residual chlorine/chloramine checks must be performed at minimum

A) after every patient treatment

B) when the softener regenerates

C) once per week only

D) before each dialysis shift and every 4 hours thereafter

21 / 50

21) When arterial pressure alarm is high, the technician should first

A) change dialysate conductivity setting

B) silence the alarm if the patient feels fine

C) inspect for kinks or clots between patient and pump

D) increase blood-flow rate

22 / 50

22) Dialysate hotter than 41 °C may cause

A) hemolysis of red blood cells

B) significant hypernatremia

C) metabolic alkalosis

D) hypoglycemia

23 / 50

23) Any equipment-related adverse event such as a dialyzer rupture must be

A) ignored if the patient is stable

B) fixed without written record

C) documented on an incident report per facility policy

D) reported only to the manufacturer

24 / 50

24) Independent conductivity reading must agree with the machine within

A) ± 0.4 mS/cm

B) ± 2.0 mS/cm

C) ± 5.0 mS/cm

D) ± 1.0 mS/cm

25 / 50

25) After bleach disinfection, the circuit is rinsed until total chlorine is

A) exactly 0.5 ppm

B) undetectable on the test strip

C) 2.0 ppm

D) 5.0 ppm

26 / 50

26) Water softeners remove

A) endotoxin via ultrafiltration

B) calcium and magnesium ions via ion exchange

C) bacteria via ultraviolet light

D) chlorine and chloramines via adsorption

27 / 50

27) According to AAMI standards, the action level for total chlorine (free + combined) post-carbon tank is

A) 0.5 mg/L

B) 1.0 mg/L

C) 0.1 mg/L

D) 2.0 mg/L

28 / 50

28) Bicarbonate concentrate mixed from powder must be discarded after

A) 48 hours

B) 72 hours

C) 24 hours

D) 96 hours

29 / 50

29) Conductivity meters indirectly measure the concentration of

A) residual chlorine in the loop

B) bacteria in water

C) hemoglobin in effluent

D) electrolytes and total dissolved solids in dialysate

30 / 50

30) AAMI requires product water microbial counts to be <

A) 50 CFU/mL

B) 1000 CFU/mL

C) 100 CFU/mL

D) 500 CFU/mL

31 / 50

31) Before opening the circuit to draw a sample, you must

A) raise dialysate temperature

B) stop the blood pump and clamp the lines

C) add 1,000 units of heparin

D) silence all alarms

32 / 50

32) A post-dialysis BUN specimen is drawn after reducing blood flow to 100 mL/min for

A) 1 minute

B) 5 minutes

C) no slowdown is required

D) 15 seconds

33 / 50

33) Bicarbonate concentrate must be mixed with

A) RO reject water

B) municipal tap water directly

C) AAMI-quality water only

D) distilled water from a humidifier

34 / 50

34) During a total power failure, the technician should first

A) mix fresh bicarbonate concentrate

B) continue ultrafiltration by gravity

C) manually return the patient’s blood with a hand crank or air-return

D) reset the facility’s main breaker

35 / 50

35) Transmembrane pressure (TMP) refers to the

A) pH of bicarbonate concentrate

B) pressure difference between blood and dialysate sides of the dialyzer

C) temperature of dialysate outflow

D) speed of the blood pump

36 / 50

36) Hardness testing after softener regeneration should read

A) 10 ppm exactly

B) > 75 ppm

C) < 1 ppm as CaCO₃

D) 50 ppm minimum

37 / 50

37) Dialysate pH of 6.6 measured with pH paper means the technician should

A) raise dialysate temperature

B) take the machine out of service and investigate

C) start treatment; 6.6 is acceptable

D) add more bicarbonate powder to the mix

38 / 50

38) Activated carbon tanks primarily remove

A) endotoxin fragments

B) dissolved gases

C) calcium and magnesium ions

D) chlorine and chloramines

39 / 50

39) After chemical disinfection, dialysis machines cannot be used until residual disinfectant tests

A) negative or below manufacturer’s limit

B) exactly 1 ppm chlorine

C) above 2 ppm chloramine

D) equal to feed-water hardness

40 / 50

40) Which component specifically removes bacterial endotoxins from product water?

A) softener

B) multimedia filter

C) ultrafilter

D) carbon tank

41 / 50

41) Running an acid rinse primarily

A) calibrates conductivity probes

B) disinfects the bloodlines

C) removes carbonate scale and bicarbonate residue

D) checks air-detector function

42 / 50

42) Monthly water cultures are drawn from

A) the RO reject drain

B) any dialysis machine effluent line

C) the raw-water feed line

D) the product water port after the final ultrafilter

43 / 50

43) For post-dialysis BUN, the correct tube is typically

A) lavender EDTA

B) gray fluoride oxalate

C) red-top (no additive)

D) light-blue citrate

44 / 50

44) A conductivity meter is usually calibrated with a standard solution reading about

A) 7 mS/cm at 10 °C

B) 14 mS/cm at 25 °C

C) 25 mS/cm at 60 °C

D) 0.5 mS/cm at 4 °C

45 / 50

45) Typical RO reject (drain) water volume equals roughly

A) twice the permeate volume

B) 50 – 70 % of incoming feed water

C) 5 % of feed water

D) none; RO has no reject

46 / 50

46) To verify dialysate pH, the handheld meter is calibrated with

A) bleach solution

B) two buffer solutions that bracket the expected pH (e.g., 7.0 and 10.0)

C) plain tap water only

D) glucose standard

47 / 50

47) A high conductivity reading means dialysate has

A) too little sodium

B) high bacterial counts

C) excessive electrolyte concentration

D) low bicarbonate content

48 / 50

48) If total chlorine exceeds limits, the technician must

A) stop treatments and place machines in bypass

B) lower dialysate sodium

C) ignore; carbon removes all chlorine

D) add more sodium hypochlorite to the feed water

49 / 50

49) Pyrogenic reactions are most often traced to

A) endotoxin contamination in dialysate

B) improper blood pump occlusion

C) low bicarbonate baths

D) sodium imbalance in bath

50 / 50

50) Acid concentrate containers are color-coded

A) blue for bacterial monitoring

B) green for environmental safety

C) clear for visibility

D) red to avoid mix-ups with bicarbonate

Your score is

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