CSLB General Building (B) — All Questions

Infection control works by interrupting the chain of infection. Which set correctly lists links in that chain?

• a.Sterilizer, autoclave, and ultrasonic cleaner
• b.Infectious agent, reservoir, portal of exit, mode of transmission, portal of entry, and susceptible host✓
• c.Bacteria, viruses, fungi, and prions only
• d.Gloves, mask, eyewear, and gown

The chain of infection consists of the infectious agent, a reservoir, a portal of exit, a mode of transmission, a portal of entry, and a susceptible host; breaking any single link stops disease transmission. Sterilizers and PPE are tools used to break links, not links themselves. Listing categories of microorganisms names only one link, the infectious agent.CDC Guidelines for Infection Control in Dental Health-Care Settings

A patient's medical history lists no infectious diseases. How should the dental team treat this patient?

• a.With reduced precautions, since the history is negative
• b.With gloves only, skipping mask and eyewear
• c.With full precautions only if the patient looks unwell
• d.With standard precautions, which are applied to every patient regardless of known diagnosis✓

Standard precautions treat the blood and body fluids of every patient as potentially infectious, because many carriers of bloodborne pathogens are asymptomatic or unaware of their status. Reducing precautions based on a negative history or on appearance leaves the team unprotected against undiagnosed infections. Gloves alone do not protect the eyes and mucous membranes from spatter.CDC Guidelines for Infection Control in Dental Health-Care Settings

What is the correct sequence for putting on personal protective equipment before a dental procedure?

• a.Gown, then mask, then protective eyewear, then gloves✓
• b.Gloves, then gown, then mask, then eyewear
• c.Mask, then gloves, then gown, then eyewear
• d.Eyewear, then gloves, then mask, then gown

PPE is donned gown first, then mask, then protective eyewear, and gloves last, so that gloved hands never touch items that must be adjusted around the face and body. Putting gloves on first contaminates the gown and mask during handling. Any sequence that ends with the gown or mask requires reaching over already-gloved hands, which breaks aseptic technique.CDC Guidelines for Infection Control in Dental Health-Care Settings

An assistant's hands are visibly soiled with saliva after removing gloves. What is the correct hand hygiene action?

• a.Apply an alcohol-based hand rub and continue working
• b.Wash hands with soap and running water, because alcohol rubs are not effective on visibly soiled hands✓
• c.Wipe hands with a surface disinfectant wipe
• d.Put on a second pair of gloves without any hand hygiene

When hands are visibly soiled they must be washed with soap and running water, since alcohol-based rubs do not remove organic material and lose effectiveness in its presence. Alcohol rubs are appropriate only for hands that are not visibly soiled. Surface disinfectants are formulated for environmental surfaces and must never be applied to skin, and double gloving without hand hygiene traps contamination against the skin.CDC Guidelines for Infection Control in Dental Health-Care Settings

The team is preparing for an oral surgical procedure. Which hand hygiene method is indicated before donning sterile gloves?

• a.A quick rinse with plain water
• b.Routine handwashing with plain soap for 15 seconds
• c.Surgical hand antisepsis using an antimicrobial soap or an alcohol-based surgical hand preparation with persistent activity✓
• d.An alcohol wipe applied to the fingertips only

Before oral surgical procedures the team performs surgical hand antisepsis with an antimicrobial soap or a surgical alcohol preparation that has persistent activity, which reduces resident as well as transient flora. Plain water and a brief plain-soap wash remove only some transient organisms and are used for routine, non-surgical care. Wiping the fingertips alone leaves the rest of the hands and forearms untreated.CDC Guidelines for Infection Control in Dental Health-Care Settings

How should an instrument processing area be laid out?

• a.Clean and contaminated items may share one counter as long as they are wiped down
• b.In a single direction from the contaminated receiving and cleaning area, to preparation and packaging, to sterilization, to clean storage✓
• c.Sterile storage should be closest to the sink for convenience
• d.Packaging should occur before instruments are cleaned

The processing area must flow in one direction from dirty to clean, moving from receiving and cleaning through preparation and packaging to sterilization and finally to clean storage, so processed items are never recontaminated. Sharing a counter and placing sterile storage next to the dirty sink both invite cross-contamination. Instruments must always be cleaned before packaging, because debris shields microorganisms from the sterilant.CDC Guidelines for Infection Control in Dental Health-Care Settings

Contaminated instruments cannot be cleaned right away because the office is short-staffed. Why are they placed in a holding solution?

• a.It sterilizes the instruments while they wait
• b.It replaces the need for ultrasonic cleaning
• c.It sharpens the cutting edges of the instruments
• d.It keeps blood and debris from drying and hardening on the instruments✓

A holding solution keeps bioburden moist so it does not dry onto the instruments, which would make later cleaning far more difficult and could shield microorganisms from the sterilant. A holding solution does not sterilize or disinfect and never replaces mechanical cleaning in an ultrasonic unit or instrument washer. It has no effect on instrument sharpness.CDC Guidelines for Infection Control in Dental Health-Care Settings

Why is an ultrasonic cleaner or instrument washer preferred over hand scrubbing contaminated instruments?

• a.It eliminates the need for sterilization afterward
• b.It allows instruments to be packaged while still wet
• c.It reduces the risk of percutaneous injury by limiting direct handling of sharp contaminated instruments✓
• d.It is the only method that removes cement and impression material

Mechanical cleaning is preferred because the operator handles sharp contaminated instruments far less, which lowers the risk of a puncture injury and exposure to bloodborne pathogens. Cleaning is a preparatory step and never substitutes for sterilization. Instruments must be rinsed and dried before packaging, and hand scrubbing with a long-handled brush is still sometimes needed for stubborn set materials.CDC Guidelines for Infection Control in Dental Health-Care Settings

Which gloves should be worn when cleaning contaminated instruments and disinfecting operatory surfaces?

• a.Heavy-duty puncture-resistant utility gloves✓
• b.The same examination gloves worn during the procedure
• c.Sterile surgical gloves
• d.No gloves, provided hands are washed afterward

Puncture-resistant utility gloves are required for instrument processing and surface cleaning because thin examination gloves tear easily and offer little protection against sharp instruments and harsh chemicals. Reusing the treatment gloves spreads contamination and provides no puncture resistance. Sterile surgical gloves are intended for surgical procedures, and working barehanded around contaminated sharps is never acceptable.OSHA Bloodborne Pathogens Standard (29 CFR 1910.1030)

How often should a dental office perform biological (spore) monitoring of each sterilizer?

• a.Once a year at the annual equipment inspection
• b.Once a month
• c.Only when a sterilizer is repaired
• d.At least weekly, and also with every load containing an implantable device✓

Biological monitoring with spore tests is performed at least weekly for each sterilizer, and additionally with every load that contains an implantable device, because spores are the only method that verifies microorganisms were actually killed. Annual or monthly testing would leave failures undetected for long periods. Testing after repairs is also required, but it does not replace the routine weekly schedule.CDC Guidelines for Infection Control in Dental Health-Care Settings

Which organism is used in the spore test that verifies a steam autoclave is working?

• a.Staphylococcus aureus
• b.Mycobacterium tuberculosis
• c.Geobacillus stearothermophilus✓
• d.Escherichia coli

Geobacillus stearothermophilus spores are highly heat resistant and are used to challenge steam autoclaves and unsaturated chemical vapor sterilizers. Staphylococcus aureus and Escherichia coli are vegetative bacteria that are killed easily and cannot verify a sterilization cycle. Mycobacterium tuberculosis is used as a benchmark for disinfectant potency, not as a sterilizer spore test.

An assistant sees that the tape on a sterilization pouch has changed color and concludes the instruments inside are sterile. Why is that conclusion wrong?

• a.An external chemical indicator only shows the package was exposed to the process, not that sterilization was achieved✓
• b.Color-change tape is only used to label the date
• c.Chemical indicators are more reliable than spore tests
• d.The tape changes color only when the cycle fails

External chemical indicators distinguish processed from unprocessed packages but respond to a single parameter such as heat, so a color change does not confirm that all conditions for sterilization were met. Only biological spore testing verifies that microorganisms were killed. The tape is not a date label, it changes with successful exposure rather than with failure, and it is less definitive than a spore test.CDC Guidelines for Infection Control in Dental Health-Care Settings

Which set of parameters describes a typical steam autoclave cycle for wrapped instruments?

• a.160°F for 5 minutes at atmospheric pressure
• b.About 250°F (121°C) at 15 psi for roughly 15 to 30 minutes✓
• c.350°F for 3 minutes with no pressure
• d.212°F for 60 minutes in an open water bath

A standard gravity steam cycle for wrapped instruments runs at approximately 250°F (121°C) under 15 psi for about 15 to 30 minutes, and pressure is what raises steam above the boiling point. A cycle at 160°F would not kill spores. Dry heat sterilizers reach around 320°F to 375°F but need pressure-free chambers and longer times, and boiling water at 212°F does not sterilize.

An office sterilizes carbon steel cutting instruments that rust in a steam autoclave. Which method is most appropriate?

• a.Dry heat sterilization at approximately 320°F (160°C) for one to two hours✓
• b.Soaking in an intermediate-level surface disinfectant for ten minutes
• c.Wiping with 70 percent isopropyl alcohol
• d.Rinsing in hot tap water and air drying

Dry heat at about 320°F for one to two hours sterilizes without moisture, which protects carbon steel from corrosion and dulling. Surface disinfectants and alcohol wipes are not sterilants and cannot be used on instruments that penetrate tissue. Hot tap water and air drying accomplish neither cleaning nor sterilization.

Under the accepted classification of patient-care items, a surgical scalpel and a bone chisel are considered:

• a.Noncritical items that need only low-level disinfection
• b.Semicritical items that may be high-level disinfected
• c.Critical items that must be heat sterilized between patients✓
• d.Environmental surfaces requiring a barrier only

Critical items penetrate soft tissue or bone and must be heat sterilized after every use because any contamination poses a high risk of infection. Semicritical items such as mirrors contact mucous membranes but do not penetrate tissue, and noncritical items such as a blood pressure cuff touch only intact skin. Instruments are patient-care items, not environmental surfaces.CDC Guidelines for Infection Control in Dental Health-Care Settings

A countertop is visibly contaminated with blood after an extraction. Which product should be used after the visible blood is cleaned up?

• a.Plain soap and water only
• b.A household glass cleaner
• c.A low-level disinfectant with no tuberculocidal claim
• d.An EPA-registered intermediate-level hospital disinfectant with a tuberculocidal claim✓

Surfaces visibly contaminated with blood require an EPA-registered hospital disinfectant that is intermediate level, meaning it carries a tuberculocidal claim, after the gross contamination has been removed. Soap and water clean but do not disinfect. Glass cleaner is not a registered disinfectant, and a low-level product without a tuberculocidal claim is reserved for surfaces without blood contamination.CDC Guidelines for Infection Control in Dental Health-Care Settings

Plastic barriers cover the light handles, chair controls, and air-water syringe. How should they be managed?

• a.Wiped with disinfectant and left in place for the rest of the day
• b.Removed while still gloved after each patient, then replaced with fresh barriers after hand hygiene✓
• c.Left on for a week because they are impervious
• d.Removed only if they appear visibly soiled

Barriers are removed with gloved hands after each patient, discarded, and replaced with fresh barriers once hands have been cleaned and regloved, since the barrier surface is considered contaminated. Wiping a barrier and reusing it defeats its purpose. Contamination is frequently invisible, so leaving barriers up for a day, a week, or until they look dirty allows cross-contamination.CDC Guidelines for Infection Control in Dental Health-Care Settings

Which procedure correctly describes disinfecting an uncovered clinical contact surface between patients?

• a.Spray the disinfectant and wipe immediately, then move on
• b.Wipe with a dry paper towel and then spray
• c.Clean the surface first to remove bioburden, then apply the disinfectant and allow the full manufacturer's contact time✓
• d.Apply the disinfectant and wipe it off before it can dry

Surfaces must first be cleaned to remove bioburden, then treated with disinfectant that remains wet for the full contact time listed by the manufacturer, which is often several minutes. Spraying and wiping immediately removes the product before it can kill microorganisms. Wiping with a dry towel spreads contamination, and drying the surface early defeats the required contact time.CDC Guidelines for Infection Control in Dental Health-Care Settings

What is the recommended maximum bacterial count for water used in nonsurgical dental treatment delivered through the dental unit?

• a.No more than 500 CFU/mL of heterotrophic bacteria✓
• b.No more than 5,000 CFU/mL
• c.No more than 50,000 CFU/mL
• d.There is no recommended limit for dental unit water

Dental unit water used for nonsurgical procedures should contain no more than 500 CFU/mL of heterotrophic bacteria, the same standard applied to safe drinking water. Counts of 5,000 or 50,000 CFU/mL indicate biofilm growth in the waterlines and require treatment of the system. Sterile solutions delivered through a sterile device are used for surgical procedures instead.CDC Guidelines for Infection Control in Dental Health-Care Settings

What should be done with handpieces and other devices attached to dental unit waterlines after each patient?

• a.Wipe the outside with alcohol and reuse immediately
• b.Flush the device to discharge water and air for about 20 to 30 seconds, then clean and heat sterilize the handpiece✓
• c.Soak the handpiece in a holding solution until the end of the day
• d.Rinse the handpiece under running tap water only

Devices connected to the waterlines are flushed for roughly 20 to 30 seconds after each patient to expel material that may have entered the turbine, and handpieces are then cleaned and heat sterilized between patients. Wiping with alcohol does not sterilize an internal lumen. Soaking in a holding solution or rinsing under tap water neither cleans the internal channels nor sterilizes the device.CDC Guidelines for Infection Control in Dental Health-Care Settings

Which description matches a compliant sharps container in the operatory?

• a.A cardboard box lined with a plastic bag, emptied weekly
• b.A clear glass jar with a screw lid stored under the sink
• c.Any waste basket, as long as needles are recapped first
• d.A closable, puncture-resistant, leakproof container that is color-coded or labeled with the biohazard symbol and located as close as practical to the point of use✓

Sharps containers must be closable, puncture resistant, leakproof on the sides and bottom, labeled or color-coded for biohazard, and placed as close as feasible to where sharps are used. Cardboard, glass jars, and ordinary waste baskets are not puncture resistant and allow injuries and spills. Recapping by hand is itself prohibited and does not make a regular trash can acceptable.OSHA Bloodborne Pathogens Standard (29 CFR 1910.1030)

An assistant must recap a contaminated anesthetic needle before the dentist gives a second injection. What is the correct method?

• a.Use a one-handed scoop technique or a mechanical recapping device✓
• b.Hold the cap in one hand and guide the needle in with the other
• c.Ask a coworker to hold the cap steady
• d.Leave the needle uncapped on the tray until the next injection

Recapping is permitted only when no alternative exists, and then only with a one-handed scoop or a mechanical recapping device that keeps the free hand away from the needle. Holding the cap in the opposite hand or having a coworker hold it places a hand directly in the path of the sharp. Leaving an uncapped needle on the tray creates a serious puncture hazard for everyone in the operatory.OSHA Bloodborne Pathogens Standard (29 CFR 1910.1030)

An assistant sustains a needlestick from a contaminated needle. What is the correct FIRST action?

• a.Squeeze the wound hard to force out as much blood as possible
• b.Immediately wash the wound with soap and running water, then report the incident and seek medical evaluation✓
• c.Finish the appointment, then report the injury at the end of the day
• d.Apply a surface disinfectant to the puncture site

The first step is immediate washing of the wound with soap and running water, followed by prompt reporting so that a confidential medical evaluation, source testing, and any indicated post-exposure prophylaxis can begin without delay. Squeezing the wound is not recommended and can damage tissue. Delaying the report can push treatment outside the window in which prophylaxis is most effective, and surface disinfectants must never be applied to skin or wounds.OSHA Bloodborne Pathogens Standard (29 CFR 1910.1030)

After an exposure incident is reported, what must the employer provide?

• a.A written warning placed in the employee's personnel file
• b.A bill for the medical evaluation, payable by the employee
• c.A requirement that the employee be tested publicly in front of staff
• d.A confidential medical evaluation and follow-up, at no cost to the employee and at a reasonable time and place✓

The employer must make available a confidential medical evaluation and follow-up immediately after an exposure incident, provided at no cost to the employee and at a reasonable time and place. Charging the employee or disciplining the employee for reporting would discourage reporting and violates the standard. Test results and evaluation records are confidential and must never be handled publicly.OSHA Bloodborne Pathogens Standard (29 CFR 1910.1030)

A newly hired dental assistant will have occupational exposure to blood. What must the employer do about hepatitis B vaccination?

• a.Require the employee to buy the vaccine before the first day of work
• b.Offer the vaccine only after the employee has an exposure incident
• c.Make the vaccination series available at no cost within 10 working days of initial assignment, after required training✓
• d.Offer the vaccine only to employees who have worked at least one year

The hepatitis B vaccination series must be offered at no cost to the employee within 10 working days of initial assignment to duties with occupational exposure, after the employee has received bloodborne pathogens training. Charging the employee is prohibited. Waiting for an exposure incident or for a year of service leaves the worker unprotected during the highest-risk early period.OSHA Bloodborne Pathogens Standard (29 CFR 1910.1030)

An assistant declines the hepatitis B vaccine that the employer offers. What must happen next?

• a.The employee must be reassigned to non-clinical duties permanently
• b.The refusal is noted verbally and no record is kept
• c.The employee signs the required declination statement, and may still receive the vaccine free of charge later if she changes her mind✓
• d.The employee must pay a fee for declining

An employee who declines must sign the required declination form, and the employer must still provide the vaccination series at no cost if the employee later decides to be vaccinated while still occupationally exposed. A verbal note is not sufficient documentation. Declining is not grounds for reassignment or for any fee or penalty.OSHA Bloodborne Pathogens Standard (29 CFR 1910.1030)

A safer medical device with a retractable needle shield is installed in the office. This is an example of which control?

• a.An engineering control, because the device itself isolates or removes the hazard✓
• b.A work practice control, because it changes how a task is performed
• c.Personal protective equipment, because it is worn by the employee
• d.An administrative record, because it is documented in the exposure control plan

Engineering controls are devices that isolate or remove the bloodborne pathogen hazard from the workplace, and a self-sheathing or retractable needle is a classic example. Work practice controls change how a procedure is carried out, such as using a one-handed scoop technique. PPE is worn by the employee, and documentation in the plan is a record rather than a control.OSHA Bloodborne Pathogens Standard (29 CFR 1910.1030)

Which item from a dental procedure is considered regulated medical waste rather than general waste?

• a.A lightly spotted patient bib
• b.A gauze square saturated with blood that would release liquid if compressed✓
• c.An empty anesthetic carpule box
• d.A used paper cup

Regulated waste includes liquid or semi-liquid blood, items caked or saturated with blood that would release it if compressed, contaminated sharps, and pathological waste such as extracted teeth. A lightly spotted bib does not release liquid when squeezed and is treated as general waste. Empty packaging and paper cups carry no such contamination.OSHA Bloodborne Pathogens Standard (29 CFR 1910.1030)

How often must a dental practice review and update its written exposure control plan?

• a.Only when the practice changes owners
• b.Every five years
• c.Only after an exposure incident occurs
• d.At least annually, and whenever new tasks, procedures, or safer devices affect occupational exposure✓

The written exposure control plan must be reviewed and updated at least annually and whenever new or modified tasks and procedures, or newly available safer medical devices, change employees' exposure. A five-year cycle or an ownership-change trigger would leave the plan badly outdated. Reviewing only after an incident is reactive and does not meet the requirement for regular review.OSHA Bloodborne Pathogens Standard (29 CFR 1910.1030)

When must employees with occupational exposure receive bloodborne pathogens training?

• a.At the time of initial assignment to tasks with occupational exposure, and at least annually thereafter✓
• b.Once during the first five years of employment
• c.Only if they request it in writing
• d.Only after they have been vaccinated for hepatitis B

Training must be provided at the time of initial assignment to tasks involving occupational exposure and at least annually thereafter, with additional training whenever new tasks or procedures alter exposure. A single session in five years or training only on request leaves employees uninformed about current hazards. Vaccination status does not determine training obligations, since training must precede the vaccine offer.OSHA Bloodborne Pathogens Standard (29 CFR 1910.1030)