CCHT Technical Practice Test 2026 - Questions and Answers

Last Updated on June 30, 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) RO membranes are chemically cleaned when product-water flow drops by about

A) 2 % from baseline

B) cleaning is never done; membranes are discarded

C) 10 % from baseline

D) 50 % from baseline

2 / 50

2) Independent conductivity reading must agree with the machine within

A) ± 1.0 mS/cm

B) ± 5.0 mS/cm

C) ± 0.4 mS/cm

D) ± 2.0 mS/cm

3 / 50

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

A) add 1,000 units of heparin

B) raise dialysate temperature

C) stop the blood pump and clamp the lines

D) silence all alarms

4 / 50

4) Proper blood pump occlusion is verified using a

A) hardness test kit

B) glucose test strip

C) drip test or occlusion gauge

D) pH meter

5 / 50

5) Conductivity meters indirectly measure the concentration of

A) electrolytes and total dissolved solids in dialysate

B) residual chlorine in the loop

C) bacteria in water

D) hemoglobin in effluent

6 / 50

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

A) take the machine out of service and investigate

B) add more bicarbonate powder to the mix

C) start treatment; 6.6 is acceptable

D) raise dialysate temperature

7 / 50

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

A) twice the permeate volume

B) 50 – 70 % of incoming feed water

C) none; RO has no reject

D) 5 % of feed water

8 / 50

8) Bicarbonate concentrate mixed from powder must be discarded after

A) 24 hours

B) 48 hours

C) 96 hours

D) 72 hours

9 / 50

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

A) carbon tank

B) softener

C) multimedia filter

D) ultrafilter

10 / 50

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

A) 0.5 mS/cm at 4 °C

B) 14 mS/cm at 25 °C

C) 25 mS/cm at 60 °C

D) 7 mS/cm at 10 °C

11 / 50

11) If total chlorine exceeds limits, the technician must

A) ignore; carbon removes all chlorine

B) lower dialysate sodium

C) add more sodium hypochlorite to the feed water

D) stop treatments and place machines in bypass

12 / 50

12) A persistent high venous pressure alarm usually indicates

A) temperature out of range

B) kink in arterial line

C) clotting in the venous line or dialyzer

D) machine in bypass

13 / 50

13) Heat disinfection of dialysis machines is commonly performed

A) once every 30 days

B) only after a positive water culture

C) only if bicarbonate is reused

D) at the end of each workday

14 / 50

14) The proportioning system on a dialysis machine

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

B) sterilizes the extracorporeal circuit

C) measures venous air bubbles

D) drives the arterial blood pump

15 / 50

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

A) 5.0 ppm

B) 2.0 ppm

C) exactly 0.5 ppm

D) undetectable on the test strip

16 / 50

16) The arterial pressure monitor is located

A) after the air detector

B) between the patient access and the blood pump

C) in the dialysate effluent line

D) on the venous drip chamber

17 / 50

17) 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) plain tap water only

C) glucose standard

D) bleach solution

18 / 50

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

A) kink in arterial tubing

B) high conductance in bath

C) venous needle dislodgement

D) dialysate too cool

19 / 50

19) A dialysate temperature alarm will place the machine into

A) bypass and stop ultrafiltration

B) heat-disinfection mode

C) bleaching cycle

D) sodium-profile mode

20 / 50

20) Water softeners remove

A) calcium and magnesium ions via ion exchange

B) bacteria via ultraviolet light

C) endotoxin via ultrafiltration

D) chlorine and chloramines via adsorption

21 / 50

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

A) 5 minutes

B) 1 minute

C) no slowdown is required

D) 15 seconds

22 / 50

22) AAMI requires product water microbial counts to be <

A) 100 CFU/mL

B) 50 CFU/mL

C) 500 CFU/mL

D) 1000 CFU/mL

23 / 50

23) Activated carbon tanks primarily remove

A) dissolved gases

B) endotoxin fragments

C) calcium and magnesium ions

D) chlorine and chloramines

24 / 50

24) Monthly water cultures are drawn from

A) the RO reject drain

B) the raw-water feed line

C) the product water port after the final ultrafilter

D) any dialysis machine effluent line

25 / 50

25) Acid concentrate containers are color-coded

A) green for environmental safety

B) clear for visibility

C) blue for bacterial monitoring

D) red to avoid mix-ups with bicarbonate

26 / 50

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

A) yellow

B) red

C) green or blue (per manufacturer)

D) purple

27 / 50

27) A high conductivity reading means dialysate has

A) low bicarbonate content

B) excessive electrolyte concentration

C) too little sodium

D) high bacterial counts

28 / 50

28) The usual order of water-treatment components is

A) softener → multimedia filter → RO → carbon

B) UV → ultrafilter → multimedia → RO

C) RO → carbon → softener → ultrafilter

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

29 / 50

29) Transmembrane pressure (TMP) refers to the

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

B) temperature of dialysate outflow

C) speed of the blood pump

D) pH of bicarbonate concentrate

30 / 50

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

A) after every patient treatment

B) once per week only

C) when the softener regenerates

D) before each dialysis shift and every 4 hours thereafter

31 / 50

31) Pyrogenic reactions are most often traced to

A) improper blood pump occlusion

B) low bicarbonate baths

C) sodium imbalance in bath

D) endotoxin contamination in dialysate

32 / 50

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

A) air bubbles before blood returns to the patient

B) dialysate temperature

C) pH changes in blood

D) conductivity spikes in dialysate

33 / 50

33) 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) reported only to the manufacturer

D) documented on an incident report per facility policy

34 / 50

34) Acceptable dialysate pH prior to patient connection is

A) 5.5 – 6.0

B) 4.0 – 5.0

C) 6.9 – 7.6

D) 7.9 – 8.4

35 / 50

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

A) cleaning the bicarbonate jug

B) calibrating the blood-pressure cuff

C) verifying all alarm functions operate correctly

D) culturing dialysate for bacteria

36 / 50

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

A) red-top (no additive)

B) lavender EDTA

C) gray fluoride oxalate

D) light-blue citrate

37 / 50

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

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

B) increase dialysate flow to clear the sensor

C) administer 100 mL saline bolus

D) silence the alarm and resume treatment

38 / 50

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

A) 10 EU/mL

B) 0.25 EU/mL

C) 1.0 EU/mL

D) 5.0 EU/mL

39 / 50

39) Running an acid rinse primarily

A) disinfects the bloodlines

B) checks air-detector function

C) removes carbonate scale and bicarbonate residue

D) calibrates conductivity probes

40 / 50

40) Dialysate hotter than 41 °C may cause

A) significant hypernatremia

B) hypoglycemia

C) hemolysis of red blood cells

D) metabolic alkalosis

41 / 50

41) Hardness testing after softener regeneration should read

A) > 75 ppm

B) 10 ppm exactly

C) 50 ppm minimum

D) < 1 ppm as CaCO₃

42 / 50

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

A) add electrolytes for taste correction

B) soften incoming feed water

C) remove dissolved salts and microorganisms

D) raise total dissolved solids (TDS)

43 / 50

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

A) equal to feed-water hardness

B) negative or below manufacturer’s limit

C) above 2 ppm chloramine

D) exactly 1 ppm chlorine

44 / 50

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

A) prevent bacterial biofilm growth

B) increase residual chlorine

C) soften feed water

D) lower dialysate pH

45 / 50

45) 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

46 / 50

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

A) reset the facility’s main breaker

B) mix fresh bicarbonate concentrate

C) continue ultrafiltration by gravity

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

47 / 50

47) Pre-dialysis potassium samples are drawn from the

A) dialysate drain hose

B) arterial bloodline sampling port before the pump

C) patient’s fingerstick

D) venous drip chamber

48 / 50

48) 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

49 / 50

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

A) 2.0 mg/L

B) 0.1 mg/L

C) 1.0 mg/L

D) 0.5 mg/L

50 / 50

50) 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) below 6.0 pH

D) over 0.25 EU/mL endotoxin

Your score is

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