CSLB General Building (B) — All Questions

A surgical case has just ended and the scrub person is preparing instruments for transport to the decontamination area. What is the correct point-of-use treatment?

• a.Remove gross soil and keep the instruments moist until they reach decontamination✓
• b.Allow the instruments to air dry so blood flakes off during transport
• c.Spray the instruments with saline and wrap them in a dry towel
• d.Perform a full manual wash at the sterile field before transport

Point-of-use treatment means wiping away gross soil and applying a moisture-retention product or damp towel so bioburden does not dry onto surfaces. Dried blood and protein are far harder to remove and can block sterilant contact. Saline is corrosive to instrument alloys, and full cleaning is never performed in the operating room because it creates contaminated aerosols in a sterile environment.AAMI ST79

A new employee asks why the department never uses saline to soak or moisten soiled surgical instruments. What is the correct explanation?

• a.It neutralizes enzymatic detergent and stops protein breakdown
• b.The chloride ions attack the passive layer and cause pitting and corrosion✓
• c.It raises the pH of the soak bath above the safe range for stainless steel
• d.It coagulates protein soil onto the instrument surface

Sodium chloride breaks down the chromium oxide passive layer that protects stainless steel, producing pitting, staining, and eventual instrument failure. Water with an appropriate presoak or enzymatic product is the correct choice. Protein coagulation is caused by heat, not saline, and pH shift is not the mechanism of chloride damage.AAMI ST79

What air pressure relationship should the decontamination area have compared with adjacent areas of the department?

• a.Positive pressure, so clean air is pushed toward the soiled workroom
• b.Equal pressure, so no air movement occurs between rooms
• c.Negative pressure, so contaminated air does not flow into clean areas✓
• d.Alternating pressure controlled by the sterilizer cycle

The decontamination room is held at negative pressure so airborne contaminants and aerosols generated during cleaning are drawn out and exhausted rather than escaping into preparation, packaging, or sterile storage. Positive pressure is used in the clean workroom and sterile storage. Equal or alternating pressure would allow uncontrolled migration of contaminated air.AAMI ST79

A facility engineer is rebalancing the ventilation system and asks what minimum air exchange rate the decontamination area requires. What should the technician answer?

• a.2 air exchanges per hour
• b.4 air exchanges per hour
• c.6 air exchanges per hour
• d.10 air exchanges per hour✓

A minimum of 10 air exchanges per hour is recommended for the decontamination area to dilute and remove aerosols, chemical vapors, and odors. Four air exchanges per hour is the minimum associated with sterile storage, a much lower-risk space. Two and six exchanges per hour are below the recommended level for any active reprocessing area.AAMI ST79

A facility engineer asks what temperature range the decontamination area should be maintained within. What is the correct answer?

• a.60 to 65 degrees F (16 to 18 degrees C)✓
• b.68 to 73 degrees F (20 to 23 degrees C)
• c.75 to 80 degrees F (24 to 27 degrees C)
• d.Any temperature that staff find comfortable in personal protective equipment

The decontamination area is kept cooler, roughly 60 to 65 degrees F, because staff work in full impervious personal protective equipment and the cooler air limits heat stress and microbial growth. The 68 to 73 degrees F range applies to the preparation and packaging area. Storage areas should not exceed about 75 degrees F, and comfort alone is not an acceptable engineering control.AAMI ST79

During a survey, an inspector reviews the department's daily environmental logs and asks what relative humidity range must be maintained in the work areas. What is correct?

• a.10 to 25 percent
• b.30 to 60 percent✓
• c.65 to 80 percent
• d.Humidity does not need to be monitored in decontamination

Relative humidity of roughly 30 to 60 percent limits microbial growth and static electricity while protecting packaging materials from moisture damage. Very low humidity dries out wrappers and generates static; humidity above 60 percent supports microbial proliferation and can cause packaging and stored items to absorb moisture. Humidity must be monitored and documented in all reprocessing areas, including decontamination.AAMI ST79

A technician is about to begin manual cleaning at an open sink where splashing is expected. Which personal protective equipment combination is required?

• a.Gloves and a surgical mask only
• b.A cloth lab coat, gloves, and eyeglasses
• c.Fluid-resistant gown, general-purpose utility gloves, face mask with eye protection or a full face shield, and hair covering✓
• d.A sterile gown and sterile gloves, because the instruments are contaminated

OSHA requires personal protective equipment that prevents blood or other potentially infectious material from reaching skin, mucous membranes, or street clothes, which at a decontamination sink means a fluid-resistant gown, heavy utility gloves, face and eye protection, and hair covering. Personal eyeglasses are not eye protection because they lack side and splash shielding. Sterile attire is irrelevant in decontamination, where the goal is worker protection, not product protection.OSHA 29 CFR 1910.1030

A technician is orienting a student at the ultrasonic cleaner and is asked what actually removes the soil from the instruments. What is the correct answer?

• a.Thermal disinfection at the final rinse temperature
• b.Chemical oxidation of protein by the detergent
• c.High-velocity water jets directed at instrument surfaces
• d.Cavitation, in which microscopic bubbles form and implode against instrument surfaces✓

High-frequency sound waves create low-pressure zones where tiny bubbles form and then collapse, and the energy released by that implosion dislodges fine soil from crevices, box locks, and serrations. Thermal disinfection and spray-jet impingement are mechanisms of washer-disinfectors, not ultrasonic units. Detergent assists cavitation but is not itself the cleaning action.AAMI ST79

An ultrasonic cleaner has just been filled with fresh solution at the start of the shift. Why must the unit be degassed before instruments are processed?

• a.Dissolved air in fresh solution cushions the sound waves and prevents effective cavitation✓
• b.Degassing raises the solution to the required thermal disinfection temperature
• c.Degassing removes residual detergent from the previous shift
• d.Degassing sterilizes the solution so instruments leave the unit sterile

Fresh water holds dissolved gas that absorbs ultrasonic energy and dampens bubble formation, so the unit is run empty for several minutes to drive the gas out and restore full cavitation. Degassing is not a heating, rinsing, or sterilizing step. An ultrasonic cleaner never sterilizes; it is a cleaning device only.AAMI ST79

A technician loads a mixed basket of stainless steel clamps, chrome-plated retractors, and aluminum instruments into the ultrasonic cleaner. What is the problem with this load?

• a.The basket exceeds the maximum weight rating of the transducer
• b.Mixing dissimilar metals in the same ultrasonic bath can cause electrolytic corrosion and plating transfer✓
• c.Aluminum instruments cannot be cleaned by any mechanical method
• d.Chrome-plated instruments must be processed in the ultrasonic twice

When different metals sit in the same conductive bath, ions migrate between them and produce staining, etching, and plating deposits, so instruments should be sorted by metal type. Aluminum can be mechanically cleaned when a compatible neutral or low-alkaline detergent is used. Weight rating and double processing are not the concerns raised by a mixed-metal load.AAMI ST79

A technician fills the wash sink with very hot water to speed up cleaning. Why must manual cleaning water stay below approximately 140 degrees F (60 degrees C)?

• a.Higher temperatures cause the detergent to foam excessively and overflow the sink
• b.Higher temperatures make it impossible to see instruments below the water line
• c.Heat above that point coagulates protein soil and bonds it to the instrument surface✓
• d.Higher temperatures deactivate the chlorides that dissolve blood

Protein denatures and coagulates with heat, so hot water effectively bakes blood and tissue onto instruments and makes removal much harder. Enzymatic detergents also lose activity outside the temperature window on the label. Foaming, visibility, and chloride activity are not the reason for the temperature limit.AAMI ST79

Most instrument manufacturers specify a neutral pH detergent for routine cleaning. What pH range is considered neutral?

• a.pH 1 to 4
• b.pH 4 to 6
• c.pH 9 to 11
• d.pH 6 to 8✓

Neutral detergents fall roughly between pH 6 and 8 and are the safest choice for the widest range of instrument materials, including anodized aluminum and delicate coatings. Strongly acidic products near pH 1 to 4 are reserved for removing mineral scale and rust deposits, and highly alkaline products near pH 9 to 11 attack aluminum and certain finishes even though they cut heavy soil. Selection must always follow the device manufacturer instructions for use.AAMI ST79

A washer-disinfector is being validated and the question arises about which water quality is required for the final rinse. What is correct?

• a.Critical water, which has been treated to remove minerals, ions, and endotoxins✓
• b.Utility water straight from the municipal tap
• c.Softened water only, with no additional treatment
• d.Distilled water heated to at least 180 degrees F but not otherwise treated

Critical water is extensively treated by processes such as reverse osmosis or deionization so that the final rinse does not deposit minerals, ions, or endotoxin residues on devices that will contact sterile tissue. Utility water is acceptable for flushing, washing, and initial rinsing but leaves residues on the final product. Softening alone removes hardness ions but not the full range of contaminants, and temperature does not substitute for treatment.AAMI ST79

A technician is scrubbing a hinged instrument with a brush at the decontamination sink and is spraying water droplets into the air. What is the correct technique?

• a.Brush more slowly under a running faucet so droplets fall back into the sink
• b.Keep the instrument and the brush fully submerged beneath the water surface while brushing✓
• c.Brush above the water line so soil is visible and can be rinsed away immediately
• d.Substitute a high-pressure water gun for the brush at all times

Brushing under the surface of the water contains splash and prevents the release of contaminated aerosols that expose the worker and the room air. Working above the water line, even slowly under a faucet, still generates droplets. Pressurized water guns have their place for lumens but must be used with additional splash protection and do not replace submerged brushing.AAMI ST79

What is the purpose of the elevated-temperature rinse phase, often around 180 degrees F or higher, in a washer-disinfector cycle?

• a.It sterilizes the instruments so they can bypass terminal sterilization
• b.It activates the enzymatic detergent so proteins continue to break down
• c.It provides thermal disinfection that reduces microbial load and improves drying✓
• d.It cools the load gradually to prevent thermal shock to delicate instruments

The hot rinse delivers thermal disinfection, lowering the bioburden so items can be safely handled in the clean workroom, and the residual heat helps the load dry. Thermal disinfection is not sterilization, so terminal sterilization is still required for critical devices. Enzymes are destroyed at that temperature, and the phase heats rather than cools the load.AAMI ST79

A department is writing its quality plan and must set a frequency for cleaning verification testing of its mechanical washers. What should the plan specify?

• a.Only when a visible soil complaint is reported by the operating room
• b.Once per quarter, at the same time as preventive maintenance
• c.Once per month, at the start of the month
• d.At least weekly, and preferably each day the washer is used✓

Routine cleaning verification with a commercial soil test device confirms the washer is still removing soil, and the recommendation is at least weekly with daily testing preferred. Waiting for a complaint is reactive and allows contaminated devices to reach patients. Quarterly and monthly intervals are too infrequent to catch a spray arm blockage, pump failure, or chemical delivery problem in time.AAMI ST79

A new sterile processing department is being designed. Which statement describes correct workflow?

• a.Work flows in one direction only, from soiled receiving through decontamination to clean assembly, sterilization, and storage✓
• b.Clean and soiled items may share a corridor as long as they travel at different times of day
• c.Staff may move freely between decontamination and assembly as long as gloves are changed
• d.Sterilizer loading may occur from either the clean or the soiled side depending on staffing

Unidirectional flow with physical separation between soiled and clean areas is the fundamental design principle that prevents recontamination of processed items. Time separation on a shared corridor does not remove residual contamination or airborne risk. Moving between areas requires full removal of protective attire and hand hygiene, not just a glove change, and sterilizers are always loaded from the clean side.AAMI ST79

Soiled instruments must be transported from the operating room to the decontamination area on a different floor. What is required?

• a.An open cart covered with a clean sheet and moved by the fastest route
• b.A closed or covered leak-proof container or cart labeled with a biohazard symbol or color coded✓
• c.A rigid sterilization container with the filters removed for ventilation
• d.Sealed plastic bags placed inside a food-service transport cart

OSHA requires contaminated items to be transported in containers that prevent leakage and are labeled or color coded so anyone encountering them knows the contents are biohazardous. A cloth sheet is not leak proof and does not warn other staff. Sterilization containers are not soiled-transport containers, and mixing biohazard transport with food-service equipment is prohibited.OSHA 29 CFR 1910.1030

A decontamination area is equipped with three sinks. What is the intended use of each?

• a.Soak, sterilize, and dry
• b.Rinse, disinfect, and lubricate
• c.Wash, intermediate rinse, and final rinse✓
• d.Presoak, ultrasonic, and inspection

The standard three-sink configuration separates the wash bath from an intermediate rinse and then a final rinse, usually with treated water, so detergent and loosened soil are not carried forward onto clean items. Sterilization, disinfection, and lubrication never take place in a decontamination sink. Ultrasonic cleaning and inspection are done in dedicated equipment and areas, not in the sink bays themselves.AAMI ST79

A lumened suction instrument arrives in decontamination. Which cleaning practice is correct?

• a.Soak the device for one hour and rely on the soak to clear the lumen
• b.Run the device through the ultrasonic cleaner only, since brushes cannot reach the channel
• c.Flush the lumen with a high-pressure air gun before any liquid contacts the device
• d.Flush the channel with detergent solution and brush it with a brush of the correct diameter and length, then rinse thoroughly✓

Lumens require mechanical action delivered by a brush that actually contacts the internal wall along the full channel length, followed by thorough flushing and rinsing. A brush that is too small does not touch the walls and one that is too large cannot pass. Soaking alone, ultrasonic alone, or blowing air through a dry contaminated channel will not remove adherent biofilm and soil.AAMI ST79

Instrument sets are consistently arriving in decontamination with hard, dried blood in box locks and serrations. What is the most likely root cause?

• a.Point-of-use treatment is not being performed and the sets sit too long before processing✓
• b.The washer-disinfector detergent concentration is set too high
• c.The decontamination area humidity is above 60 percent
• d.The transport carts are being covered too tightly

Dried, baked-on soil is the classic signature of missing point-of-use treatment combined with delayed transport, and the fix is education of the procedural areas plus prompt pickup. Excess detergent does not create dried soil, and it would be observed after washing rather than on arrival. High humidity would tend to keep soil moist, and covering carts protects rather than harms the instruments.AAMI ST79

A technician keeps a covered coffee cup on a shelf above the decontamination sink. How should this be addressed?

• a.It is acceptable because the cup has a lid and is not on the work surface
• b.It is prohibited because eating, drinking, and storing food or drink are not allowed where occupational exposure occurs✓
• c.It is acceptable if the technician removes gloves before drinking
• d.It is prohibited only if the cup is within the splash zone of the sink

OSHA bans eating, drinking, smoking, applying cosmetics, handling contact lenses, and storing food or drink in any area where occupational exposure to blood or other potentially infectious material is reasonably anticipated. A lid does not protect against contaminated aerosols settling on the exterior of the container. Glove removal and distance from the sink do not create an exemption.OSHA 29 CFR 1910.1030

Instruments are coming out of the washer with a chalky white film. Water testing shows high hardness. What is the appropriate corrective action?

• a.Increase the alkaline detergent concentration to dissolve the film
• b.Extend the wash phase by ten minutes on every cycle
• c.Address water quality with treatment such as softening or deionization, and use a descaling product as directed for existing deposits✓
• d.Lower the final rinse temperature so minerals stay in solution

A white chalky film is mineral scale from hard water depositing during rinsing and drying, and the durable fix is treating the water supply, with an acidic descaler used per manufacturer instructions to remove existing buildup. Adding alkaline detergent does not dissolve mineral scale and risks damaging aluminum. Longer wash times and cooler rinses do not change the mineral content of the water.AAMI ST79

An enzymatic cleaner label lists protease, lipase, and amylase. What does this combination indicate?

• a.The product will disinfect as well as clean
• b.The product is intended for use only in ultrasonic cleaners
• c.The product can be used at any temperature without losing effectiveness
• d.The product targets several soil types, breaking down protein, fat, and starch or carbohydrate residues✓

Each enzyme acts on a specific substrate, so protease attacks protein such as blood and tissue, lipase attacks fatty deposits, and amylase attacks starches and carbohydrates. Enzymatic cleaners clean but do not disinfect or sterilize. They are used in sinks and mechanical equipment alike, and their activity is temperature dependent and destroyed by hot water.AAMI ST79

A technician finishes cleaning and is about to walk into the clean assembly area. What must occur?

• a.Remove all personal protective equipment in the decontamination area, dispose of or store it properly, and perform hand hygiene before entering✓
• b.Keep the gown on but remove gloves, since the gown protects the clean area
• c.Walk through quickly while holding the door with an elbow to avoid touching surfaces
• d.Change gloves only, because the rest of the attire has not touched instruments

Protective attire worn in decontamination is considered contaminated and must be removed before leaving the area, followed by hand hygiene, so contamination is not carried into the clean workroom. A worn gown is a contaminated item, not a barrier that protects clean space. Speed and elbow technique do not remove contamination from attire or hands.OSHA 29 CFR 1910.1030

A case cart cannot be picked up for several hours because of staffing. What is the best interim measure for the soiled instruments?

• a.Immerse the entire set in a covered basin of tap water until pickup
• b.Apply an instrument pre-treatment foam, spray, or moisture-retaining product per the manufacturer instructions and keep the set covered✓
• c.Wrap the set in a saline-dampened towel
• d.Place the set in a warming cabinet so soil stays soft

Pre-treatment products are designed to hold moisture against the soil for extended periods and prevent it from drying, which preserves cleanability during unavoidable delays. Full immersion in open basins creates heavy containers, splash risk, and possible corrosion, and standing water can support microbial growth. Saline damages instruments, and heat accelerates drying and can coagulate protein.AAMI ST79

Why should the lid of an ultrasonic cleaner remain closed while the unit is running?

• a.To maintain the water temperature required for thermal disinfection
• b.To prevent the detergent from evaporating and changing concentration
• c.To contain the contaminated aerosols that the cavitation process releases into the air✓
• d.To keep instruments from floating out of the basket

Cavitation drives contaminated droplets off the solution surface, so keeping the lid closed protects staff and the room air from aerosolized bioburden. Ultrasonic cleaners do not perform thermal disinfection. Evaporation and floating instruments are minor operational issues, not the safety-driven reason for the closed lid.AAMI ST79

During a competency review, a technician is asked to explain why cleaning is considered the single most important step in instrument reprocessing. Which answer is correct?

• a.Cleaning removes the need for a chemical indicator inside the package
• b.Cleaning is what actually kills the spores present on the instrument
• c.Cleaning is required only for instruments that will be used on sterile tissue
• d.Residual soil shields microorganisms from the sterilant, so an item that is not clean cannot be reliably sterilized✓

Blood, tissue, and biofilm form a physical barrier that sterilant cannot penetrate, so any organism protected under residual soil may survive a technically correct sterilization cycle. Cleaning itself does not kill spores; it removes and reduces bioburden so the sterilant can work. Indicators monitor the process and cannot compensate for poor cleaning, and every reusable device requires cleaning regardless of its Spaulding classification.AAMI ST79