- Departmental Considerations 15%
- Cleaning, Decontamination and Disinfection 21%
- Preparation and Packaging 21%
- Sterilization Process 21%
- Sterile Storage, Transport and Inventory Management 9%
- Patient Care Equipment and Distribution 5%
- Professional Development and Human Relation Skills 8%
Free · 2026 · 21% of the HSPA CRCST CRCST Cleaning, Decontamination and Disinfection practice questions
Cleaning, Decontamination and Disinfection is 21% of the HSPA CRCST. Answer 10 questions (6 on Cleaning, Decontamination and Disinfection) and see your score by domain, with every answer explained. Free, no sign-up.
After cleaning, a technician notices a whitish, chalky film on several stainless steel instruments. The supervisor says the deposits are mineral scale from hard water. Which type of cleaning product is designed to remove this deposit, if the instrument IFU allows it?
Tap an answer, or press A to D
PPE and bloodborne pathogens, microbiology, point-of-use care, manual and mechanical cleaning, detergents and water quality, equipment testing, and disinfection by Spaulding category.
What the HSPA CRCST exam tests in Cleaning, Decontamination and Disinfection
- Area safety: OSHA Bloodborne Pathogens Standard, PPE types, donning and doffing, when to change and how to dispose of PPE, sharps safety, wet floors, chemical safety, eyewash and shower stations, equipment operator manuals
- Microbiology and infection prevention: chain of infection, modes of transmission, cross-contamination, bacteria and bacterial spores, viruses, fungi, prions and Creutzfeldt-Jakob disease (CJD), biofilm, endotoxin, relative resistance to disinfection and sterilization
- Receiving soiled items: point-of-use treatment, safe transport into decontamination, inspecting for and reporting inadequate point-of-use cleaning, sorting reusable and disposable items, sharps and waste disposal (regulated medical waste vs regular trash), third-party reprocessing and sustainability
- Work-area preparation and cleaning chemistry: cleaning tools and brushes (selection, size, single-use vs reusable), detergents (enzymatic, pH-neutral, alkaline, acidic), dilution, temperature and expiration per IFU, checking and replenishing chemicals in equipment, water quality (utility vs critical water)
- Manual cleaning: following the device IFU (including loaned trays), disassembling, opening and sorting instruments, sink method, water temperature, preventing aerosols, brushing and flushing lumens, high-pressure water and air guns, visual inspection with magnification
- Mechanical cleaning and equipment care: ultrasonic cleaners, washer-disinfectors, cart washers, automated endoscope reprocessors (AERs), load configuration and cycle selection, operator cleaning and maintenance (strainers, drains, spray arms, manifolds, baskets), chemical feed lines and detergent dosage, alarms and malfunctions, outlets (regular, emergency)
- Cleaning quality tests: efficacy testing for washer-disinfectors, ultrasonic cleaners, AERs and cart washers, test frequency, documenting and interpreting results, cleaning verification tests for instruments
- Disinfection: Spaulding classification (critical, semi-critical, noncritical), levels of disinfection, disinfectant families (quaternary ammonium compounds, phenolics, alcohols, halogens, aldehydes, peroxygens), exposure time, concentration and minimum effective concentration (MEC) testing, temperature, rinsing, documentation, corrective actions for failed tests, safety measures, drying, storage and transport of disinfected items
- Special processing risks: Toxic Anterior Segment Syndrome (TASS) prevention for intraocular instruments, CJD/prion precautions, flexible endoscope leak testing and cleaning basics
High-yield cleaning, decontamination and disinfection facts
- Cleaning removes soil and most microbes, and it is the most important reprocessing step: soil shields microbes from sterilants and inactivates chemicals.
- Definitions: - Decontamination makes an item safe to handle. - Disinfection kills most microbes but not necessarily spores. - Sterilization kills all microbial life, including spores.
- OSHA Bloodborne Pathogens Standard (29 CFR 1910.1030): - Standard precautions: treat all blood and other potentially infectious materials as infectious. - Written exposure control plan, reviewed at least annually. - PPE, hepatitis B vaccine and training provided free to the employee. - Hepatitis B vaccine offered within 10 working days of assignment; an employee who declines signs a declination. - Training at assignment and at least annually.
- Bloodborne pathogens records and labels: - Training records kept 3 years; medical records kept for duration of employment plus 30 years. - Biohazard labels are fluorescent orange or orange-red; red bags or containers may substitute. - Sharps containers are closable, puncture-resistant and leakproof on sides and bottom, kept upright, and replaced before overfilling.
- Sharps injury or splash: wash with soap and water (flush eyes or mucous membranes with water), report immediately, and get post-exposure evaluation.
- Decon PPE: fluid-resistant gown with sleeves, heavy-duty long-cuffed utility gloves, mask plus goggles or a face shield, hair cover, and shoe covers or boots.
| Rank | Agent |
|---|---|
| 1 | Prions (CJD) |
| 2 | Bacterial spores |
| 3 | Mycobacteria (TB) |
| 4 | Small non-enveloped viruses |
| 5 | Fungi |
| 6 | Vegetative bacteria |
| 7 | Enveloped (lipid) viruses |
The full CRCST High-Yield Cram Sheet comes with full prep.
Common cleaning, decontamination and disinfection traps
- A washer-disinfector cycle makes items safe to handle, not sterile.
- Pre-rinse with cool water; hot water bakes protein onto instruments.
- Keep soiled instruments moist with water or an enzymatic product, never saline.
- Brush below the water line; brushing above it creates aerosols.
- Don't mix dissimilar metals in the ultrasonic, and always rinse after ultrasonic cleaning.
- Final rinse uses critical water, not utility water.
- A solution that passes MEC but is past its reuse life is still discarded.
- Leak test a flexible scope before immersion.
Free CRCST cleaning, decontamination and disinfection practice questions
Question 1
A new technician takes a flexible gastroscope from its transport container and connects it directly to the automated endoscope reprocessor (AER). He reasons that the AER will both clean and disinfect it. What is the error?
- AThe AER should simply be run twice in a row to make up for skipping manual steps
- BThe scope should be steam sterilized first so it is safe to handle at the AER
- CThe scope should first be soaked in saline so the AER can remove the loosened soil
- DThe scope must first be leak tested and manually cleaned, including brushing and flushing its channels
Show answer and explanation
Answer: D. Leak testing comes before immersion, and manual cleaning removes soil and biofilm. The AER then performs high-level disinfection on a clean scope per the IFU.
Why not A: Repeating the automated cycle doesn't remove soil in channels the way brushing does. It also skips the leak test, which detects damage.
Why not B: Flexible endoscopes are heat-sensitive and would be damaged by steam. Steam sterilization also doesn't replace cleaning.
Why not C: Saline is corrosive and is never used to keep soil moist. Soaking doesn't replace leak testing and brushing.
Remember: Flexible endoscopes are leak tested and manually cleaned before the AER; the AER doesn't replace these steps.
Question 2
A technician finishes an ultrasonic cycle for a basket of hinged orthopedic instruments. The instruments look clean, so the technician plans to lift the basket out and send it straight to the prep and pack area to dry. What is the main problem with this plan?
- AThe instruments should be degassed after the cycle to release trapped air from the box locks.
- BThe instruments should cool down inside the ultrasonic tank before they are removed.
- CLoosened soil and detergent stay in the solution and on the items, so they must be rinsed thoroughly.
- DUltrasonic solution acts as a disinfectant, so the instruments need a longer soak instead.
Show answer and explanation
Answer: C. Cavitation loosens soil into the solution rather than removing it from the tank, so instruments must be rinsed after ultrasonic cleaning.
Why not A: Degassing is done to fresh solution before use, not to instruments after the cycle.
Why not B: Cooling in the tank is not a required step and does not remove residue left from the solution.
Why not D: Ultrasonic cleaning is a cleaning process, not disinfection, and soaking longer leaves the residue in place.
Remember: Ultrasonic cleaning loosens soil into the solution, so instruments must be rinsed thoroughly afterward.
Question 3
To get a heavily soiled orthopedic tray clean faster, a technician fills the sink with the hottest tap water available before adding the enzymatic detergent. What is the main problem with this practice?
- AHot tap water contains chlorine, so critical water must be used to prepare every enzymatic cleaning solution
- BHot water dilutes the enzymes, so double the measured amount of detergent should be added to compensate
- CHot water is acceptable, but the instruments must soak twice as long because enzymes act more slowly when heated
- DVery hot water can inactivate the enzymes and set protein soil, so the solution should be made at the temperature in the detergent IFU
Show answer and explanation
Answer: D. Enzymes work within a limited temperature range, usually lukewarm. Excess heat both inactivates them and coagulates blood on the instruments.
Why not A: Utility water is appropriate for washing solutions. Critical water is reserved for the final rinse, and the real issue here is temperature.
Why not B: Temperature does not change the concentration. Adding extra detergent leaves residue and still leaves the enzymes heat-damaged.
Why not C: Heated enzymes do not just slow down. They are inactivated, and a longer soak cannot restore them.
Remember: Prepare enzymatic detergents at the temperature in the product's IFU (typically lukewarm), because excess heat inactivates enzymes and fixes protein soil.
Question 4
A technician finds a single-use device mixed in with reusable instruments on a returned tray. The hospital has a program with an FDA-registered third-party reprocessor for this type of device. What should the technician do?
- ADiscard it in the sharps container, because single-use items can never be reused.
- BWash it in the sink and return it to the OR's disposable supply stock.
- CPlace it in the designated collection container for the third-party reprocessor.
- DClean and sterilize it with the tray so it can be used for the next case.
Show answer and explanation
Answer: C. Eligible single-use devices are segregated and sent to the FDA-registered reprocessor through the facility's program, which supports sustainability without in-house reprocessing.
Why not A: When an approved third-party program exists, eligible items go to the reprocessor. Sharps containers are only for sharps.
Why not B: Returning a used single-use device to stock after informal washing is unsafe and bypasses regulated reprocessing.
Why not D: Hospitals that reprocess single-use devices in-house are regulated as manufacturers. The device should not go through routine processing.
Remember: Sort single-use devices from reusables early and send eligible ones only to an FDA-registered third-party reprocessor, never reprocessing them in-house.
Question 5
To save time, a technician places stainless steel retractors and several chrome-plated instruments in the same ultrasonic cleaner basket. Her supervisor stops her. What is the main reason?
- ACombining the two groups would put the basket over the 25-pound weight limit for instrument sets
- BPlacing different metals together in the bath can cause ion transfer that etches or plates the instruments
- CStainless steel needs a higher frequency setting than chrome-plated items in an ultrasonic unit
- DChrome plating absorbs the sound energy, so cavitation can't reach the stainless steel items
Show answer and explanation
Answer: B. Dissimilar metals in the ultrasonic solution can exchange ions, which damages the instrument surfaces through etching or plating.
Why not A: The 25-lb limit applies to packaged sets for sterilization. It has nothing to do with mixing metals in an ultrasonic cleaner.
Why not C: Frequency is set by the equipment and the IFU, not by metal type in this way. This doesn't explain why mixed loads are prohibited.
Why not D: This is not the concern. The problem with mixed metals is a chemical reaction between them in the solution, not chrome blocking the sound energy.
Remember: Don't mix dissimilar metals (such as stainless steel with chrome-plated, brass or aluminum items) in the same ultrasonic cycle.
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