22 Decontamination & Cleaning Practice Questions & Answers

1. 1. A surgical case ends and the instruments will not be picked up for about 45 minutes. Which point-of-use practice best preserves the instruments in a condition that can be effectively cleaned later?

   • A.Spray the instruments with a surface disinfectant and set the tray aside
   • B.Allow the instruments to air-dry so that soil does not spread during transport
   • C.Soak the instruments in a basin of normal saline until transport
   • D.Cover the instruments with a towel moistened with water, or apply an enzymatic pre-treatment spray, foam or gel✓ Answer

   Point-of-use treatment works by keeping soil soft and hydrated so it can still be removed, which is why water-moistened towels and purpose-made enzymatic pre-treatment products are used. Saline must never be used for soaking or moistening because chloride ions attack the passive layer of stainless steel and cause pitting and corrosion, and letting soil dry bonds it to the surface and seeds biofilm. Pre-treatment products are wetting/pre-cleaning agents, not disinfectants, and never replace cleaning.

   Source: HSPA CRCST Exam Content Outline, Section 2 (Cleaning, Decontamination and Disinfection), Item Preparation — point-of-use treatment; ANSI/AAMI ST79 point-of-use treatmentReport a problem with this question

2. 2. Why is allowing blood and body fluids to dry on instruments treated as a genuine reprocessing failure rather than a cosmetic problem?

   • A.Dried soil removes the instrument's protective lubricant film, so every item must be re-lubricated
   • B.Dried soil is harmless once the item is sterilized, because steam readily penetrates organic material
   • C.Dried soil shifts the pH of the detergent solution into the acidic range, corroding the instrument
   • D.Dried soil bonds tightly to the surface and supports biofilm, whose self-produced matrix shields organisms from detergents, disinfectants and sterilants✓ Answer

   Biofilm is a community of microorganisms embedded in a self-produced extracellular polysaccharide matrix, and it begins forming within minutes to hours once soil is left to dry on a surface or in a lumen. Once mature it is dramatically more resistant to disinfectants and sterilants than free-floating organisms and is not reliably removed by routine cleaning, so prompt moisture retention at the point of use — not harder scrubbing later — is the control. Residual organic soil also physically blocks sterilant contact, so an item that is not clean cannot be reliably disinfected or sterilized.

   Source: HSPA CRCST Exam Content Outline, Section 2 — biofilm and cross contamination; CDC/HICPAC Guideline for Disinfection and Sterilization (cleaning must precede disinfection/sterilization)Report a problem with this question

3. 3. A loaner tray arrives in decontamination with visibly dried, caked blood on the instruments, and no point-of-use treatment appears to have been performed. What is the appropriate response?

   • A.Scrub the hardened soil off with a stiff metal-bristled brush to save time
   • B.Place the tray directly into the ultrasonic cleaner to break up the gross soil, skipping manual cleaning
   • C.Run the tray through the washer-disinfector twice and release it if it looks clean afterward
   • D.Report the inadequate point-of-use treatment, then follow the device manufacturer's IFU for extended soaking and thorough manual cleaning before any mechanical processing✓ Answer

   Technicians are expected to inspect incoming items and report inadequate point-of-use cleaning, because the failure will recur unless it is fed back to the procedural area. The remedy for dried soil is the manufacturer's written instructions — typically extended enzymatic soaking followed by thorough manual cleaning — because mechanical equipment is validated to remove ordinary residual soil, not baked-on debris, and a second wash cycle does not fix an inadequately pre-cleaned device. Metal-bristled brushes are not used on delicate or finished surfaces, and the ultrasonic is not a gross-soil remover.

   Source: HSPA CRCST Exam Content Outline, Section 2, Work Area Preparation — inspecting for and reporting inadequate point-of-use cleaning; Item Preparation — cleaning per manufacturer's IFU including loaned traysReport a problem with this question

4. 4. Under bloodborne pathogen requirements, how must contaminated instruments be handled while being transported from the procedure area to decontamination?

   • A.Placed in a clear plastic bag so the set can be inventoried before it enters decontamination
   • B.Contained in a closed, leak-proof, puncture-resistant container or cart that is labeled with the biohazard symbol or color-coded red✓ Answer
   • C.Carried in an open basin covered with a dry huck towel so staff can see the contents
   • D.Rinsed with a disinfectant at the point of use, after which labeling of the container is unnecessary

   OSHA's bloodborne pathogens standard requires contaminated items to be contained during transport in closed, leak-proof containers that are labeled with the biohazard symbol or color-coded, so that spills, aerosols and sharps injuries cannot occur en route and anyone encountering the container knows its hazard. Open basins and thin bags fail because they leak and can be punctured, and a disinfectant rinse at the point of use does not decontaminate the device or remove the labeling requirement. Contaminated reusable sharps must be placed in puncture-resistant containers immediately or as soon as possible after use.

   Source: OSHA 29 CFR 1910.1030(d)(2) and (d)(4) — containment and labeling of contaminated items and reusable sharps; HSPA CRCST Exam Content Outline, Section 2 — safe transportation into decontaminationReport a problem with this question

5. 5. Why must soiled instruments and clean or sterile supplies never be moved together on the same cart at the same time?

   • A.Because regulations permit only one biohazard label per elevator trip
   • B.Because the combined weight exceeds the load rating of most transport carts
   • C.Because organisms and moisture can transfer from the soiled items to the clean ones; if a single cart serves both purposes it must be decontaminated between uses✓ Answer
   • D.Because clean packaged supplies absorb odors from soiled instruments and become unacceptable to the operating room

   Sterile processing is built on a one-way, dirty-to-clean workflow, and mixing soiled and clean items on the same conveyance creates the exact cross-contamination pathway that workflow is designed to eliminate. Many facilities designate separate soiled and clean carts, and where a cart is used for both it must be decontaminated in a cart washer or manually per IFU between uses; case carts returning from the OR are treated as contaminated in their entirety. Soiled transport carts are covered or fully enclosed for the same containment reason.

   Source: HSPA CRCST Exam Content Outline, Section 2 — safe transportation of contaminated items; OSHA 29 CFR 1910.1030(d)(2) containment during transportReport a problem with this question

6. 6. The decontamination room is kept under negative pressure relative to adjacent areas, with its air exhausted rather than recirculated. What does this arrangement accomplish?

   • A.Air flows into the room and is exhausted out, so aerosols and airborne contaminants generated during cleaning are not carried into clean areas✓ Answer
   • B.It keeps the room warm enough for enzymatic detergents to reach full activity
   • C.It raises the boiling point of the detergent solutions so that wash water cleans more effectively
   • D.It sterilizes the incoming air so that cleaned instruments cannot be recontaminated before packaging

   Cleaning generates aerosols and airborne contamination, so decontamination is a physically separated, restricted space held at negative pressure with dedicated exhaust: air moves from cleaner areas into decontamination and out of the building, never the reverse. This is a containment mechanism, not a cleaning or comfort measure, and it works in tandem with the one-way dirty-to-clean workflow and with PPE that is removed before leaving the area. Specific temperature, humidity and air-change values are set by the applicable HVAC standard for the facility rather than by any single sterile-processing rule of thumb.

   Source: HSPA CRCST Exam Content Outline, Sections 1–2 — work area design, traffic control and negative pressure in decontamination; ANSI/ASHRAE/ASHE Standard 170 (soiled workroom: negative pressure, air exhausted)Report a problem with this question

7. 7. What is the correct sequence for donning personal protective equipment before entering the decontamination area?

   • A.Mask, then gloves, then gown, then eye protection
   • B.Eye protection, then gloves, then gown, then mask
   • C.Gown, then mask, then eye protection or face shield, then gloves✓ Answer
   • D.Gloves, then gown, then mask, then eye protection

   Gloves are donned last so that their cuffs cover the gown sleeves and the gloves themselves stay clean while the other items are adjusted, which would be impossible if gloves went on first. Decontamination PPE is full-barrier: a fluid-resistant gown or jumpsuit, heavy-duty puncture-resistant gloves rather than exam gloves, a mask with eye protection or a full face shield, hair covering, and fluid-resistant shoe covers. The employer must supply this PPE at no cost to the worker.

   Source: HSPA CRCST Exam Content Outline, Section 2, Area-Specific Safety — PPE types and donning/doffing; OSHA 29 CFR 1910.1030(d)(3) employer-provided PPEReport a problem with this question

8. 8. A technician finishes a shift in decontamination and is heading to the break room. Which action reflects correct practice?

   • A.Remove the gown first while keeping gloves on, so the hands stay protected until the very end
   • B.Remove eye protection first because it is the least contaminated item, then remove gloves
   • C.Keep the PPE on while passing through the clean assembly area, and remove it at the department exit
   • D.Remove gloves first as the most contaminated item, then the gown, then eye protection, then the mask, perform hand hygiene, and leave all PPE in decontamination✓ Answer

   Doffing is ordered from most contaminated to least so that contaminated surfaces are never carried across the face or hands: gloves come off first, then the gown, then eye protection, then the mask, with hand hygiene afterward. PPE is removed before leaving decontamination and is never worn into clean workrooms, offices or break areas, because that would defeat the one-way dirty-to-clean workflow and carry contamination into areas where it can reach clean devices and food.

   Source: HSPA CRCST Exam Content Outline, Section 2, Area-Specific Safety — PPE doffing sequence and disposal; CDC PPE sequence guidanceReport a problem with this question

9. 9. Why are instruments brushed while fully submerged beneath the surface of the cleaning solution during manual cleaning?

   • A.Submersion softens stainless steel so that adherent soil releases more readily
   • B.Submersion keeps brush bristles from wearing out, extending the life of the brush
   • C.The detergent is chemically inactive above the water line and only works below it
   • D.Submerged brushing prevents contaminated droplets from becoming aerosols that can be inhaled or settle on the technician, surfaces and clean items✓ Answer

   Brushing, flushing and spraying above the water line flings contaminated droplets into the breathing zone and onto surrounding surfaces, so the solution itself is used as a splash barrier by keeping the item and the brush below the surface. The same reasoning governs high-pressure water and air guns, which are used only with appropriate face protection and splash containment. This is an exposure-control measure that complements, rather than replaces, full-barrier PPE.

   Source: HSPA CRCST Exam Content Outline, Section 2, Item Preparation — manual cleaning process, prevention of aerosols; OSHA 29 CFR 1910.1030(d)(2) work practice controlsReport a problem with this question

10. 10. Manual cleaning water is kept cool — generally below about 110°F (43°C) — and must never be allowed to exceed roughly 140°F (60°C). What is the mechanism behind this limit?

    • A.Hot water drives the detergent's pH into the alkaline range, which pits the instrument surface
    • B.Hot water evaporates enzymes into the air and creates an inhalation hazard for the technician
    • C.Hot water expands stainless steel enough that hinged joints and box locks seize permanently
    • D.Heat coagulates blood and other proteins, fixing them onto the instrument surface where they become far harder to remove✓ Answer

    Protein denatures and coagulates with heat, and coagulated blood bonds to the instrument surface much like cooked egg to a pan, so any soil that is heat-fixed early in the process may never be removed. Enzymatic detergents add a second constraint: they need warmth to work efficiently but are themselves denatured by excessive heat, which is why most IFUs specify a warm rather than hot range. Because the exact validated temperature is device- and chemistry-specific, the manufacturer's written instructions govern.

    Source: HSPA CRCST Exam Content Outline, Section 2, Item Preparation — manual cleaning process, water temperature; ANSI/AAMI ST79 (cool water to prevent protein coagulation)Report a problem with this question

11. 11. When selecting a brush to clean the internal channel of a lumened instrument, what matters most?

    • A.That the brush be as stiff as possible so it can dislodge the heaviest soil
    • B.That the brush diameter and length match the lumen as specified in the device IFU, so the bristles contact the entire internal wall through the full length of the channel✓ Answer
    • C.That the brush be shorter than the lumen so it cannot scratch the far end
    • D.That the brush have metal bristles, which are appropriate for any stainless steel lumen

    Cleaning a lumen is mechanical: soil is removed only where bristles physically touch the wall, so a brush that is undersized slides through without contact and leaves soil and biofilm behind, while an oversized brush cannot pass or may damage the channel. A brush too short to traverse the channel leaves an uncleaned segment that no later step can reach. Brushes must be inspected for worn or splayed bristles, and are either single-use or cleaned and decontaminated at least daily per the IFU and facility policy.

    Source: HSPA CRCST Exam Content Outline, Section 2, Item Preparation — brush selection, size, care, single-use vs reusable; cleaning per manufacturer's IFUReport a problem with this question

12. 12. How does an ultrasonic cleaner remove soil, and what does the process actually accomplish?

    • A.Ultraviolet energy loosens soil while simultaneously killing organisms on the instrument surface
    • B.Chemical dissolution of organic soil removes the need for prior gross-soil removal or manual cleaning
    • C.High-frequency sound waves generate micro-bubbles that implode (cavitation) and pull fine soil out of crevices and hard-to-reach areas; the process cleans but does not disinfect or sterilize✓ Answer
    • D.Heated water impingement dislodges soil, and the elevated temperature also disinfects the instruments

    Ultrasonic cleaning works by cavitation: high-frequency sound waves create low-pressure micro-bubbles that collapse violently against the instrument, and the energy released lifts fine soil from box locks, serrations and other areas a brush cannot reach. It is a cleaning process only — it has no antimicrobial claim — so gross soil must be removed first, items must be fully submerged with hinges open, and instruments must be rinsed afterward to carry away loosened soil and detergent. Lumens require a sonic irrigator or flushing attachment, because simple immersion does not move solution through a channel.

    Source: HSPA CRCST Exam Content Outline, Section 2 — utilization of mechanical cleaning equipment (ultrasonic); CDC/HICPAC Guideline for Disinfection and Sterilization (ultrasonic cleaning removes soil, is not a disinfection process)Report a problem with this question

13. 13. Freshly prepared solution in an ultrasonic cleaner must be degassed before instruments are processed. Why?

    • A.Degassing kills the microorganisms carried into the tank with the previous load
    • B.Degassing is how the solution is brought up to the temperature range enzymatic detergents require
    • C.Dissolved air in fresh solution cushions and dampens the imploding bubbles, so cavitation — and therefore cleaning — is markedly reduced✓ Answer
    • D.Degassing is needed to dissolve the powdered detergent, which otherwise will not go into solution

    Cavitation depends on bubbles collapsing violently, and dissolved air makes the bubbles compressible so they cushion instead of imploding, which is why fresh solution must be run through a degas cycle after every change. Related operating rules follow the same containment and performance logic: the lid stays closed during operation so aerosols are contained, items are fully submerged with hinges open, dissimilar metals are not mixed, and the solution is changed at least each shift or when visibly soiled per the IFU.

    Source: HSPA CRCST Exam Content Outline, Section 2 — equipment operation (ultrasonic cleaner); ANSI/AAMI ST79 ultrasonic cleaner operation (degassing of fresh solution)Report a problem with this question

14. 14. Why should stainless steel instruments not be processed in the same ultrasonic load as chrome-plated, brass, aluminum or copper items?

    • A.Contact between dissimilar metals in a conductive solution sets up galvanic (electrolytic) action that can pit one metal and deposit plating onto another, permanently damaging the instruments✓ Answer
    • B.Mixing metals causes the detergent to foam, which overflows the tank
    • C.Aluminum absorbs so much ultrasonic energy that it cracks the transducer tank
    • D.Different metals require different sound frequencies before cavitation will occur at all

    A detergent solution is an electrolyte, so two dissimilar metals in contact within it behave like a small battery: the more active metal corrodes and pits while dissolved ions plate out on the other surface, leaving stains and permanent damage. Ultrasonic energy accelerates this because it constantly refreshes solution at the metal surfaces. Separating loads by material — and excluding items the IFU says are damaged by or absorb ultrasonic energy, such as many rubber, silicone, plastic, lensed and air-powered devices — prevents it.

    Source: HSPA CRCST Exam Content Outline, Section 2 — utilization of mechanical cleaning equipment, load configuration; ANSI/AAMI ST79 (do not mix dissimilar metals in ultrasonic cleaners)Report a problem with this question

15. 15. The first phase of a typical washer-disinfector cycle is a cold-water pre-wash or pre-rinse. Why is cold water used at this stage rather than hot?

    • A.Hot water would coagulate blood and other proteins onto the instruments, fixing soil that the later wash phases could no longer remove✓ Answer
    • B.Cold water protects the bearings of the rotating spray arms from thermal stress
    • C.Cold water is required to activate the enzymatic detergent used in the next phase
    • D.Cold water is used to conserve energy at the start of a long cycle

    The pre-wash exists to flush away gross blood and protein before any heat is applied, and it must be cold because heat denatures and coagulates protein onto the surface, creating soil that no subsequent phase can dislodge. The remaining phases build on that foundation in order: enzymatic or detergent wash with impingement, rinse, a high-temperature thermal rinse that delivers thermal disinfection, optional lubrication, and drying. Understanding this sequence is what makes the cold first phase counterintuitive but correct — candidates instinctively assume hotter is always better.

    Source: HSPA CRCST Exam Content Outline, Section 2 — equipment operation (washer-disinfector), cycle selection; ANSI/AAMI ST79 washer-disinfector cycle phasesReport a problem with this question

16. 16. Which loading practice will give a washer-disinfector the best chance of actually cleaning the load?

    • A.Open all hinged instruments, place cupped or concave items on edge or angled so water drains rather than pools, avoid stacking or overloading, and connect lumened devices to flush manifolds✓ Answer
    • B.Stack instrument trays on top of one another to maximize the number of sets per cycle
    • C.Close box locks and ratchets so instruments cannot shift and damage one another during the cycle
    • D.Place lightweight and delicate items on the bottom rack so heavier trays above shield them from the spray

    A washer cleans by spray impingement, so cleaning only happens where water and detergent physically strike the surface: stacking and overloading create shadowed areas, closed box locks hide the joint surfaces where soil hides, and cupped items that trap water dilute detergent and prevent drying. Heavy items belong on the bottom so they do not block spray to lighter items above, spray arms must be verified to rotate freely and be unclogged, and lumens must be attached to manifolds because water will not otherwise travel through a channel. The device IFU determines which items may be mechanically processed at all.

    Source: HSPA CRCST Exam Content Outline, Section 2 — utilization of mechanical cleaning equipment: load configuration and cycle selectionReport a problem with this question

17. 17. Why must detergents used in washer-disinfectors and ultrasonic cleaners be low-foaming formulations?

    • A.Foam clogs the biohazard exhaust filter and causes the chamber to lose negative pressure
    • B.Foam drives the solution pH upward into the corrosive alkaline range
    • C.Foam cushions instrument surfaces and absorbs the spray impingement and cavitation energy that these machines depend on to remove soil✓ Answer
    • D.Foam permanently stains stainless steel instruments a bluish color

    Mechanical cleaning is energy transfer — water jets striking the surface in a washer, imploding bubbles in an ultrasonic — and a blanket of foam absorbs that energy before it reaches the instrument, so a high-foaming manual detergent placed in a machine can silently defeat the entire cycle. This is why cleaning chemistries are selected for the specific equipment and dispensed at the dilution the IFU specifies, rather than being interchangeable between the sink and the washer. Using the wrong chemistry is a common cause of a failed cleaning-verification test.

    Source: HSPA CRCST Exam Content Outline, Section 2, Work Area Preparation — chemical identification and preparation following the IFU; ANSI/AAMI ST79 (low-foaming detergents for mechanical cleaning equipment)Report a problem with this question

18. 18. Why is the final rinse of cleaned instruments performed with critical water (extensively treated, for example by reverse osmosis or deionization) rather than untreated tap water?

    • A.Because tap water in a healthcare facility always contains residual detergent from the plumbing
    • B.Because treated water is delivered warmer, which speeds drying of the instruments
    • C.Because critical water disinfects the instruments as it rinses, which utility water cannot do
    • D.Because utility water carries dissolved minerals, ions, endotoxin and other contaminants that dry onto devices and cause spotting, staining, scale, corrosion and residues linked to patient reactions such as toxic anterior segment syndrome✓ Answer

    Water quality is treated as a formal processing parameter: utility water is acceptable for flushing, washing and intermediate rinsing, while critical water — extensively treated to remove minerals, ions, organic material and endotoxin — is reserved for the final rinse and steam generation, because whatever the last rinse leaves behind dries onto the device and goes to the patient. Hard water in particular reduces detergent efficacy and deposits a mineral film, and residues on ophthalmic instruments are a recognized contributor to toxic anterior segment syndrome. Steam and steam condensate are also recognized as a tested water category.

    Source: ANSI/AAMI ST108, Water for the Processing of Medical Devices — utility water, critical water and steam categories; HSPA CRCST Exam Content Outline, Section 2 — water quality identificationReport a problem with this question

19. 19. A flexible endoscope is being reprocessed in a department equipped with an automated endoscope reprocessor (AER). Which statement describes correct practice?

    • A.The scope is leak tested before immersion, then manually cleaned and brushed according to its IFU; the AER performs high-level disinfection but never replaces manual cleaning✓ Answer
    • B.The cleaning phase of the AER replaces manual cleaning, so brushing channels by hand is redundant
    • C.Leak testing is performed after high-level disinfection, since a leak would show up most clearly on a processed scope
    • D.The scope should be immersed immediately on arrival and leak tested only if a problem is suspected

    Leak testing comes before immersion because fluid entering a breached scope destroys internal components and creates an uncleanable contaminated space, so the test protects both the device and the patient. Manual cleaning with channel brushing is mandatory regardless of automation, since organic soil and biofilm inside long narrow channels will inactivate the high-level disinfectant and shield organisms from it — an item that is not clean cannot be disinfected. A borescope may be used to inspect channels that cannot be seen directly, and the scope's own IFU governs brush sizes, channel adapters and contact conditions.

    Source: HSPA CRCST Exam Content Outline, Section 2 — equipment operation (leak tester, AER) and manual cleaning per IFU; CDC/HICPAC Guideline for Disinfection and Sterilization (cleaning must precede high-level disinfection of endoscopes)Report a problem with this question

20. 20. Which statement about detergent pH in instrument cleaning is correct?

    • A.Neutral-pH detergents may be used only on plastic items, since they lack the strength for stainless steel
    • B.Acidic detergents are the routine first choice for surgical instruments because low pH dissolves blood most effectively
    • C.Once an instrument has been rinsed, the pH of the detergent used has no bearing on the instrument's condition
    • D.Strongly alkaline detergents attack aluminum and anodized coatings, acidic detergents are used against mineral scale and are corrosive if left in contact, and neutral or near-neutral detergents are the general-purpose choice compatible with most instrument materials✓ Answer

    pH determines both cleaning power and material compatibility, which is why chemistry is matched to soil and substrate: alkaline detergents cut heavy organic soil and are common in washer-disinfectors but corrode aluminum and anodized finishes and demand thorough rinsing or neutralizing, acidic products target mineral deposits and scale, and neutral formulations (roughly pH 6–8) are safe across the widest range of materials. Enzymatic detergents belong to this picture as protein-, starch- and fat-digesting cleaners — they are cleaners, not disinfectants, and must be rinsed away thoroughly. The device and chemistry IFUs together decide which agent may be used on a given instrument.

    Source: HSPA CRCST Exam Content Outline, Section 2, Work Area Preparation — selection of the correct cleaning agent per the IFU; ANSI/AAMI ST79 cleaning chemistries and material compatibilityReport a problem with this question

21. 21. A technician doubles the amount of detergent concentrate added to the sink, reasoning that a stronger solution will clean better. Why is this incorrect?

    • A.It voids the equipment warranty but has no effect on the instruments themselves
    • B.It raises the water temperature above 140°F (60°C), which coagulates protein
    • C.Concentration outside the dilution validated in the IFU leaves residue and film that stains instruments, resists rinsing and can contribute to patient reactions such as toxic anterior segment syndrome✓ Answer
    • D.It converts a neutral detergent into a high-level disinfectant, which is not permitted at the sink

    Detergent performance is validated at a specific dilution, temperature and contact time, so deviating in either direction breaks the validation: under-dilution wastes product and leaves difficult-to-rinse residue and film, while over-dilution simply fails to clean. Residue is not cosmetic — it can stain and pit instruments, interfere with subsequent processing, and on ophthalmic devices is implicated in toxic anterior segment syndrome. Solutions should be measured and dosed as the IFU directs, checked against expiration dating, and remade rather than topped off when they become soiled.

    Source: HSPA CRCST Exam Content Outline, Section 2, Work Area Preparation — chemical preparation, dilution and expiration per the manufacturer's IFU; ANSI/AAMI ST79 (methods for reducing the risk of TASS)Report a problem with this question

22. 22. How often should mechanical cleaning equipment such as washer-disinfectors and ultrasonic cleaners be challenged with cleaning verification test devices, and what must happen when a test fails?

    • A.Only when soil is visible on processed instruments; a failed test is rerun until it passes
    • B.Monthly; a failed test may be disregarded if the instruments in the load look visually clean
    • C.Upon installation, each day the equipment is used, and after major repairs; a failure takes the machine out of service, holds or reprocesses the affected loads, and requires investigation and documented corrective action✓ Answer
    • D.Only once a year by the manufacturer during preventive maintenance; a failure is logged and the cycle simply repeated

    Cleaning verification exists because cleaning efficacy cannot be judged by appearance, so the equipment is challenged on installation, each day of use and after major repairs — daily testing catches drift such as clogged spray arms, blocked strainers, incorrect chemical dosing, wrong water temperature or poor load configuration before many loads are affected. A failure is a quality event, not a nuisance: the machine comes out of service, affected loads are held or reprocessed, the root cause is investigated and corrected, and the action is documented. Complementary tools include soil-challenge indicators for washers, foil ablation or commercial cavitation indicators for ultrasonics, and residual protein or ATP tests for individual devices cleaned manually.

    Source: ANSI/AAMI ST79, section 13.2 — mechanical cleaning equipment testing upon installation, each day of use, and after major repairs; HSPA CRCST Exam Content Outline, Section 2, Quality Tests and Maintenance/TroubleshootingReport a problem with this question

Practice questions based on the HSPA CRCST Certification Exam Content Outline, ANSI/AAMI ST79 sterility-assurance practice, and CDC/HICPAC disinfection and sterilization guidance. CRCST is a mark of the Healthcare Sterile Processing Association; this site is not affiliated with or endorsed by HSPA. Always follow the device manufacturer's written instructions for use, your facility's policies, and the current edition of the applicable standards. About the CRCST exam →