CCHT Technical Practice Test 2026 - Questions and Answers

Last Updated on October 1, 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) At power-up, a dialysis machine self-test includes

A) cleaning the bicarbonate jug

B) calibrating the blood-pressure cuff

C) culturing dialysate for bacteria

D) verifying all alarm functions operate correctly

2 / 50

2) Monthly water cultures are drawn from

A) the RO reject drain

B) the product water port after the final ultrafilter

C) any dialysis machine effluent line

D) the raw-water feed line

3 / 50

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

A) 7 mS/cm at 10 °C

B) 25 mS/cm at 60 °C

C) 0.5 mS/cm at 4 °C

D) 14 mS/cm at 25 °C

4 / 50

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

A) silence the alarm and resume treatment

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

C) administer 100 mL saline bolus

D) increase dialysate flow to clear the sensor

5 / 50

5) Hardness testing after softener regeneration should read

A) 50 ppm minimum

B) < 1 ppm as CaCO₃

C) > 75 ppm

D) 10 ppm exactly

6 / 50

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

A) ignored if the patient is stable

B) reported only to the manufacturer

C) fixed without written record

D) documented on an incident report per facility policy

7 / 50

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

A) negative or below manufacturer’s limit

B) above 2 ppm chloramine

C) exactly 1 ppm chlorine

D) equal to feed-water hardness

8 / 50

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

A) increase blood-flow rate

B) silence the alarm if the patient feels fine

C) change dialysate conductivity setting

D) inspect for kinks or clots between patient and pump

9 / 50

9) 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

10 / 50

10) A dialysate temperature alarm will place the machine into

A) bypass and stop ultrafiltration

B) bleaching cycle

C) sodium-profile mode

D) heat-disinfection mode

11 / 50

11) Pre-dialysis potassium samples are drawn from the

A) venous drip chamber

B) patient’s fingerstick

C) dialysate drain hose

D) arterial bloodline sampling port before the pump

12 / 50

12) Heat disinfection of dialysis machines is commonly performed

A) only after a positive water culture

B) once every 30 days

C) only if bicarbonate is reused

D) at the end of each workday

13 / 50

13) Bicarbonate concentrate mixed from powder must be discarded after

A) 48 hours

B) 96 hours

C) 24 hours

D) 72 hours

14 / 50

14) The proportioning system on a dialysis machine

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

B) measures venous air bubbles

C) sterilizes the extracorporeal circuit

D) drives the arterial blood pump

15 / 50

15) 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

16 / 50

16) Conductivity meters indirectly measure the concentration of

A) bacteria in water

B) residual chlorine in the loop

C) electrolytes and total dissolved solids in dialysate

D) hemoglobin in effluent

17 / 50

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

A) purple

B) red

C) yellow

D) green or blue (per manufacturer)

18 / 50

18) Independent conductivity reading must agree with the machine within

A) ± 5.0 mS/cm

B) ± 1.0 mS/cm

C) ± 0.4 mS/cm

D) ± 2.0 mS/cm

19 / 50

19) 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) 2.0 mg/L

D) 0.1 mg/L

20 / 50

20) 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

21 / 50

21) AAMI requires product water microbial counts to be <

A) 100 CFU/mL

B) 1000 CFU/mL

C) 500 CFU/mL

D) 50 CFU/mL

22 / 50

22) Water softeners remove

A) calcium and magnesium ions via ion exchange

B) bacteria via ultraviolet light

C) chlorine and chloramines via adsorption

D) endotoxin via ultrafiltration

23 / 50

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

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

B) glucose standard

C) plain tap water only

D) bleach solution

24 / 50

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

A) dialysate temperature

B) pH changes in blood

C) air bubbles before blood returns to the patient

D) conductivity spikes in dialysate

25 / 50

25) Proper blood pump occlusion is verified using a

A) pH meter

B) drip test or occlusion gauge

C) hardness test kit

D) glucose test strip

26 / 50

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

A) remove dissolved salts and microorganisms

B) add electrolytes for taste correction

C) soften incoming feed water

D) raise total dissolved solids (TDS)

27 / 50

27) Dialysate hotter than 41 °C may cause

A) metabolic alkalosis

B) significant hypernatremia

C) hypoglycemia

D) hemolysis of red blood cells

28 / 50

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

A) 15 seconds

B) 5 minutes

C) 1 minute

D) no slowdown is required

29 / 50

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

A) once per week only

B) before each dialysis shift and every 4 hours thereafter

C) after every patient treatment

D) when the softener regenerates

30 / 50

30) Acid concentrate containers are color-coded

A) red to avoid mix-ups with bicarbonate

B) green for environmental safety

C) blue for bacterial monitoring

D) clear for visibility

31 / 50

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

A) carbon tank

B) softener

C) multimedia filter

D) ultrafilter

32 / 50

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

A) kink in arterial tubing

B) venous needle dislodgement

C) dialysate too cool

D) high conductance in bath

33 / 50

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

A) add 1,000 units of heparin

B) stop the blood pump and clamp the lines

C) silence all alarms

D) raise dialysate temperature

34 / 50

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

A) 50 – 70 % of incoming feed water

B) twice the permeate volume

C) 5 % of feed water

D) none; RO has no reject

35 / 50

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

A) 10 EU/mL

B) 5.0 EU/mL

C) 1.0 EU/mL

D) 0.25 EU/mL

36 / 50

36) A persistent high venous pressure alarm usually indicates

A) machine in bypass

B) temperature out of range

C) kink in arterial line

D) clotting in the venous line or dialyzer

37 / 50

37) Running an acid rinse primarily

A) removes carbonate scale and bicarbonate residue

B) calibrates conductivity probes

C) disinfects the bloodlines

D) checks air-detector function

38 / 50

38) Acceptable dialysate pH prior to patient connection is

A) 4.0 – 5.0

B) 7.9 – 8.4

C) 6.9 – 7.6

D) 5.5 – 6.0

39 / 50

39) If total chlorine exceeds limits, the technician must

A) stop treatments and place machines in bypass

B) lower dialysate sodium

C) add more sodium hypochlorite to the feed water

D) ignore; carbon removes all chlorine

40 / 50

40) Transmembrane pressure (TMP) refers to the

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

B) pH of bicarbonate concentrate

C) temperature of dialysate outflow

D) speed of the blood pump

41 / 50

41) A high conductivity reading means dialysate has

A) excessive electrolyte concentration

B) too little sodium

C) high bacterial counts

D) low bicarbonate content

42 / 50

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

A) add more bicarbonate powder to the mix

B) take the machine out of service and investigate

C) raise dialysate temperature

D) start treatment; 6.6 is acceptable

43 / 50

43) The arterial pressure monitor is located

A) in the dialysate effluent line

B) after the air detector

C) on the venous drip chamber

D) between the patient access and the blood pump

44 / 50

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

A) soften feed water

B) lower dialysate pH

C) increase residual chlorine

D) prevent bacterial biofilm growth

45 / 50

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

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

B) under 30 °C

C) over 0.25 EU/mL endotoxin

D) below 6.0 pH

46 / 50

46) 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

47 / 50

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

A) 2 % from baseline

B) 10 % from baseline

C) 50 % from baseline

D) cleaning is never done; membranes are discarded

48 / 50

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

A) gray fluoride oxalate

B) light-blue citrate

C) red-top (no additive)

D) lavender EDTA

49 / 50

49) Activated carbon tanks primarily remove

A) calcium and magnesium ions

B) chlorine and chloramines

C) endotoxin fragments

D) dissolved gases

50 / 50

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

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

B) continue ultrafiltration by gravity

C) reset the facility’s main breaker

D) mix fresh bicarbonate concentrate

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