CCHT Technical Practice Test 2025 - Questions and Answers

Last Updated on June 14, 2025

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) 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

2 / 50

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

A) venous needle dislodgement

B) kink in arterial tubing

C) high conductance in bath

D) dialysate too cool

3 / 50

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

A) none; RO has no reject

B) 5 % of feed water

C) 50 – 70 % of incoming feed water

D) twice the permeate volume

4 / 50

4) The arterial pressure monitor is located

A) on the venous drip chamber

B) after the air detector

C) in the dialysate effluent line

D) between the patient access and the blood pump

5 / 50

5) The usual order of water-treatment components is

A) softener → multimedia filter → RO → carbon

B) RO → carbon → softener → ultrafilter

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

D) UV → ultrafilter → multimedia → RO

6 / 50

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

A) below 6.0 pH

B) over 0.25 EU/mL endotoxin

C) under 30 °C

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

7 / 50

7) Proper blood pump occlusion is verified using a

A) hardness test kit

B) pH meter

C) drip test or occlusion gauge

D) glucose test strip

8 / 50

8) Activated carbon tanks primarily remove

A) endotoxin fragments

B) dissolved gases

C) chlorine and chloramines

D) calcium and magnesium ions

9 / 50

9) 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

10 / 50

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

A) light-blue citrate

B) lavender EDTA

C) red-top (no additive)

D) gray fluoride oxalate

11 / 50

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

A) 5.0 ppm

B) undetectable on the test strip

C) exactly 0.5 ppm

D) 2.0 ppm

12 / 50

12) Acceptable dialysate pH prior to patient connection is

A) 6.9 – 7.6

B) 5.5 – 6.0

C) 4.0 – 5.0

D) 7.9 – 8.4

13 / 50

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

A) 25 mS/cm at 60 °C

B) 0.5 mS/cm at 4 °C

C) 14 mS/cm at 25 °C

D) 7 mS/cm at 10 °C

14 / 50

14) 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

15 / 50

15) Independent conductivity reading must agree with the machine within

A) ± 0.4 mS/cm

B) ± 5.0 mS/cm

C) ± 1.0 mS/cm

D) ± 2.0 mS/cm

16 / 50

16) Monthly water cultures are drawn from

A) any dialysis machine effluent line

B) the RO reject drain

C) the raw-water feed line

D) the product water port after the final ultrafilter

17 / 50

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

A) take the machine out of service and investigate

B) start treatment; 6.6 is acceptable

C) raise dialysate temperature

D) add more bicarbonate powder to the mix

18 / 50

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

A) 2.0 mg/L

B) 1.0 mg/L

C) 0.1 mg/L

D) 0.5 mg/L

19 / 50

19) Bicarbonate concentrate mixed from powder must be discarded after

A) 96 hours

B) 48 hours

C) 72 hours

D) 24 hours

20 / 50

20) 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

21 / 50

21) Dialysate hotter than 41 °C may cause

A) hemolysis of red blood cells

B) metabolic alkalosis

C) significant hypernatremia

D) hypoglycemia

22 / 50

22) Bicarbonate concentrate must be mixed with

A) AAMI-quality water only

B) RO reject water

C) distilled water from a humidifier

D) municipal tap water directly

23 / 50

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

A) administer 100 mL saline bolus

B) increase dialysate flow to clear the sensor

C) silence the alarm and resume treatment

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

24 / 50

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

A) raise total dissolved solids (TDS)

B) remove dissolved salts and microorganisms

C) add electrolytes for taste correction

D) soften incoming feed water

25 / 50

25) A dialysate temperature alarm will place the machine into

A) bleaching cycle

B) heat-disinfection mode

C) sodium-profile mode

D) bypass and stop ultrafiltration

26 / 50

26) If total chlorine exceeds limits, the technician must

A) lower dialysate sodium

B) stop treatments and place machines in bypass

C) add more sodium hypochlorite to the feed water

D) ignore; carbon removes all chlorine

27 / 50

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

A) silence all alarms

B) add 1,000 units of heparin

C) stop the blood pump and clamp the lines

D) raise dialysate temperature

28 / 50

28) 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

29 / 50

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

A) inspect for kinks or clots between patient and pump

B) change dialysate conductivity setting

C) increase blood-flow rate

D) silence the alarm if the patient feels fine

30 / 50

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

A) plain tap water only

B) glucose standard

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

D) bleach solution

31 / 50

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

A) 0.25 EU/mL

B) 10 EU/mL

C) 1.0 EU/mL

D) 5.0 EU/mL

32 / 50

32) Hardness testing after softener regeneration should read

A) < 1 ppm as CaCO₃

B) 10 ppm exactly

C) 50 ppm minimum

D) > 75 ppm

33 / 50

33) Acid concentrate containers are color-coded

A) clear for visibility

B) green for environmental safety

C) blue for bacterial monitoring

D) red to avoid mix-ups with bicarbonate

34 / 50

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

A) exactly 1 ppm chlorine

B) above 2 ppm chloramine

C) equal to feed-water hardness

D) negative or below manufacturer’s limit

35 / 50

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

A) reset the facility’s main breaker

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

C) mix fresh bicarbonate concentrate

D) continue ultrafiltration by gravity

36 / 50

36) 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

37 / 50

37) Running an acid rinse primarily

A) checks air-detector function

B) removes carbonate scale and bicarbonate residue

C) calibrates conductivity probes

D) disinfects the bloodlines

38 / 50

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

A) air bubbles before blood returns to the patient

B) pH changes in blood

C) conductivity spikes in dialysate

D) dialysate temperature

39 / 50

39) Pre-dialysis potassium samples are drawn from the

A) patient’s fingerstick

B) arterial bloodline sampling port before the pump

C) venous drip chamber

D) dialysate drain hose

40 / 50

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

A) ignored if the patient is stable

B) documented on an incident report per facility policy

C) fixed without written record

D) reported only to the manufacturer

41 / 50

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

A) soften feed water

B) increase residual chlorine

C) prevent bacterial biofilm growth

D) lower dialysate pH

42 / 50

42) The proportioning system on a dialysis machine

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

B) measures venous air bubbles

C) drives the arterial blood pump

D) sterilizes the extracorporeal circuit

43 / 50

43) A high conductivity reading means dialysate has

A) high bacterial counts

B) low bicarbonate content

C) excessive electrolyte concentration

D) too little sodium

44 / 50

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

A) culturing dialysate for bacteria

B) verifying all alarm functions operate correctly

C) calibrating the blood-pressure cuff

D) cleaning the bicarbonate jug

45 / 50

45) Heat disinfection of dialysis machines is commonly performed

A) at the end of each workday

B) only after a positive water culture

C) only if bicarbonate is reused

D) once every 30 days

46 / 50

46) Transmembrane pressure (TMP) refers to the

A) pH of bicarbonate concentrate

B) speed of the blood pump

C) temperature of dialysate outflow

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

47 / 50

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

A) ultrafilter

B) softener

C) carbon tank

D) multimedia filter

48 / 50

48) Conductivity meters indirectly measure the concentration of

A) electrolytes and total dissolved solids in dialysate

B) bacteria in water

C) residual chlorine in the loop

D) hemoglobin in effluent

49 / 50

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

A) green or blue (per manufacturer)

B) yellow

C) red

D) purple

50 / 50

50) AAMI requires product water microbial counts to be <

A) 100 CFU/mL

B) 50 CFU/mL

C) 1000 CFU/mL

D) 500 CFU/mL

Your score is

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