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Question 1Cleaning, Disinfection and Environmental Hygiene Practices

A technician is about to damp mop a hallway outside patient rooms. Which action best prevents slips and falls?

  1. Ask patients to stay in their rooms instead of using warning signs
  2. Place a wet-floor sign only after the mopping has been completed
  3. Place wet-floor signs at both approaches before mopping starts Correct answer.
  4. Mop during shift change so that fewer people are in the hallway

Explanation

Warning signs must be in place before and while a floor is wet, positioned where people approach the wet area, and left until the floor is dry. Verbal instructions do not reach visitors or staff who arrive later, and scheduling cannot replace signage.

Question 2Cleaning, Disinfection and Environmental Hygiene Practices

An environmental services technician removes gloves after cleaning a patient bathroom. What should be done next?

  1. Rinse the hands with water only and continue working
  2. Put on a fresh pair of gloves before touching the cart
  3. Perform hand hygiene before touching clean supplies Correct answer.
  4. Wipe the gloves with disinfectant and keep working

Explanation

Gloves can harbor organisms and are never a substitute for hand hygiene; hands must be cleaned immediately after glove removal and before contact with clean equipment or supplies. Plain water does not remove or kill organisms effectively.

Question 3Cleaning, Disinfection and Environmental Hygiene Practices

Which set of items is classified as high-touch surfaces that require frequent disinfection in a patient room?

  1. Ceiling tiles, air vents, and window glass
  2. Bed rails, call buttons, and light switches Correct answer.
  3. Inside cabinets, supply boxes, and sealed shelves
  4. Floors, baseboards, and lower door frames

Explanation

High-touch surfaces are those contacted often by hands, such as bed rails, call buttons, light switches, and overbed tables, and they carry the greatest risk of transferring organisms. Floors, ceilings, and closed storage are low-touch and are cleaned on a different schedule.

Question 4Cleaning, Disinfection and Environmental Hygiene Practices

A technician finds a used hypodermic needle on the floor of a patient room. What is the correct action?

  1. Use tongs or a dustpan to place it in a sharps container Correct answer.
  2. Snap the needle off and discard the syringe separately
  3. Pick it up with a gloved hand and place it in the sharps box
  4. Wrap it in a paper towel and drop it in the regular trash

Explanation

Sharps must never be handled with the hands; a mechanical device such as tongs or a dustpan and brush is used to place the item directly into a rigid, puncture-resistant sharps container. Bending or breaking sharps is prohibited because it causes injury and aerosol generation.

Question 5Cleaning, Disinfection and Environmental Hygiene Practices

Which sequence reflects accepted practice for cleaning a patient room?

  1. Top to bottom, and from cleaner to dirtier areas Correct answer.
  2. Bottom to top so dirt falls onto surfaces already cleaned
  3. Floor first, then the bed rails and the overbed table
  4. Bathroom first, then the bed area, then the entry door

Explanation

Working from high to low keeps loosened soil from falling onto surfaces that are already clean, and working from cleaner to dirtier areas prevents moving contamination back into cleaner zones. Floors are done last because soil settles downward.

Question 6Cleaning, Disinfection and Environmental Hygiene Practices

A disinfectant label lists a contact time of 3 minutes. What does this require?

  1. The surface must stay wet with the product for 3 minutes Correct answer.
  2. The product must be wiped dry within 3 minutes of use
  3. The room must stay closed for 3 minutes afterward
  4. The concentrate must sit for 3 minutes before dilution

Explanation

Contact time, also called dwell time, is the period the surface must remain visibly wet with the product for the label claim to be met; the surface is then allowed to air dry or is wiped per the label. Wiping the product away early shortens the exposure and reduces efficacy.

Question 7Cleaning, Disinfection and Environmental Hygiene Practices

Which statement best describes the difference between cleaning and disinfection?

  1. Cleaning and disinfection mean the same process
  2. Disinfection applies to floors only; cleaning covers the rest
  3. Cleaning destroys spores, while disinfection removes soil
  4. Cleaning removes soil; disinfection reduces pathogens Correct answer.

Explanation

Cleaning is a physical process that removes visible soil, organic matter, and many organisms, while disinfection is a chemical process that reduces the number of pathogens on a surface. Cleaning generally must precede disinfection because soil interferes with chemical action.

Question 8Cleaning, Disinfection and Environmental Hygiene Practices

How should soiled patient linens be handled during a room cleaning?

  1. Sort clean and soiled items into piles on the bed
  2. Set them on the floor beside the cart until the room is done
  3. Shake them over the floor to remove loose debris
  4. Bag them where they are used without shaking Correct answer.

Explanation

Soiled linens are bagged at the point of generation, held away from the body, and never shaken, because shaking disperses microorganisms into the air and onto nearby surfaces. Linens are also never placed on the floor or sorted on patient beds.

Question 9Cleaning, Disinfection and Environmental Hygiene Practices

A flexible endoscope contacts mucous membranes but does not enter sterile body cavities. How is it classified and processed?

  1. Noncritical; it requires low-level disinfection
  2. Critical; it requires sterilization before reuse
  3. Semicritical; it requires high-level disinfection Correct answer.
  4. Noncritical; it needs only soap and water cleaning

Explanation

Under the Spaulding classification, items that contact intact mucous membranes are semicritical and require high-level disinfection. Critical items enter sterile tissue or the vascular system and require sterilization, while noncritical items contact only intact skin.

Question 10Cleaning, Disinfection and Environmental Hygiene Practices

Which disinfectant should be used for terminal cleaning of a room vacated by a patient with Clostridioides difficile infection?

  1. A quaternary ammonium product at its routine dilution
  2. Isopropyl alcohol wipes applied to all high-touch surfaces
  3. An EPA-registered chlorine sporicidal used per its label Correct answer.
  4. A phenolic disinfectant diluted to half its labeled strength

Explanation

C. difficile produces spores that survive routine quaternary ammonium products and alcohol, so an EPA-registered sporicidal chlorine-based product must be applied at the labeled concentration and contact time. Under-diluting a product can also cause toxicity without improving kill.

Question 11Cleaning, Disinfection and Environmental Hygiene Practices

When leaving a patient room after cleaning, which PPE item should be removed first?

  1. Gloves Correct answer.
  2. Gown
  3. Face shield or goggles
  4. Respirator or surgical mask

Explanation

Gloves are the most contaminated item and are removed first, followed by hand hygiene, then eye protection and gown, with respiratory protection removed last after leaving the room. Removing respiratory protection early exposes the technician while still in the contaminated space.

Question 12Cleaning, Disinfection and Environmental Hygiene Practices

A technician is mopping several patient rooms with the same bucket of solution. Which practice best reduces cross-contamination?

  1. Rinse the mop in the toilet of each room before continuing
  2. Add a splash of concentrate to the bucket between rooms
  3. Mop from the bathroom out into the hallway in each room
  4. Change the mop head and solution at the policy interval Correct answer.

Explanation

Solution becomes soiled and loses effectiveness as it is used, and a mop that is returned to clean solution contaminates it, so mop heads and solution are changed at the interval defined by facility policy and manufacturer instructions. Working outward from the bathroom also spreads contamination into the hallway.

Question 13Cleaning, Disinfection and Environmental Hygiene Practices

Why are cleaning cloths color-coded by area, for example one color for bathrooms and another for patient rooms?

  1. To show which cloths were laundered most recently
  2. To indicate the contact time needed on each surface
  3. To record which staff member used each cloth
  4. To prevent cross-contamination between areas Correct answer.

Explanation

Color coding keeps a cloth that has touched a higher-risk area such as a bathroom from being used in a lower-risk area, which limits the movement of pathogens between zones. The code reflects the area of use, not staff identity, laundry age, or product contact time.

Question 14Cleaning, Disinfection and Environmental Hygiene Practices

Before using a disinfectant on a hospital surface, what should the technician verify on the product label?

  1. That the fragrance is pleasant enough for patient rooms
  2. That it is EPA-registered for the intended use Correct answer.
  3. That it costs less than other products in its category
  4. That it can be mixed with other products to widen its spectrum

Explanation

A product must carry an EPA registration with a claim for the surface type and target organisms, and it must be used exactly as directed for dilution and contact time. Mixing products is dangerous and can inactivate both chemicals.

Question 15Cleaning, Disinfection and Environmental Hygiene Practices

How does terminal cleaning differ from routine daily cleaning of a patient room?

  1. It is done after discharge and covers the whole room Correct answer.
  2. It is limited to the floor and the entry door handles
  3. It uses water alone so that surfaces are not damaged
  4. It is done only while the patient is awake in the room

Explanation

Terminal cleaning occurs when the patient is discharged or transferred and includes all surfaces and items in the room, often with more thorough methods such as curtain changes and wall spot cleaning. Daily cleaning while the patient is present is a different, more limited task.

Question 16Cleaning, Disinfection and Environmental Hygiene Practices

What is the correct sequence for cleaning a blood spill on a hard floor?

  1. Absorb the spill, remove the bulk, clean, then disinfect Correct answer.
  2. Blot the blood with towels, then mop the floor with water
  3. Cover the spill with disinfectant and leave it overnight
  4. Disinfect the bulk spill first, then mop, then remove PPE

Explanation

After donning PPE, the spill is contained and absorbed, bulk material is removed, the area is cleaned of visible soil, and then an EPA-registered hospital disinfectant is applied for the full contact time. Removing organic matter first is essential because blood interferes with disinfectant action.

Question 17Cleaning, Disinfection and Environmental Hygiene Practices

How should a concentrated disinfectant be measured when preparing a working solution?

  1. Double the concentrate to be sure it is strong enough
  2. Add concentrate until the solution looks cloudy
  3. Estimate the amount from the bottle cap
  4. Use the manufacturer's dispenser or a graduated cup Correct answer.

Explanation

The labeled dilution ratio must be measured accurately with the manufacturer's dispensing system or a graduated measuring device, because under-dilution reduces efficacy and over-dilution increases cost, residue, and exposure risk. Visual estimates and appearance are not reliable indicators.

Question 18Cleaning, Disinfection and Environmental Hygiene Practices

Which item is properly discarded as regulated medical waste in a labeled biohazard container?

  1. A dressing saturated with blood Correct answer.
  2. An empty juice carton from a patient tray
  3. An empty cardboard box from supplies
  4. A used paper towel from a hallway dispenser

Explanation

Regulated medical waste includes items saturated or dripping with blood or other potentially infectious material, and these go into a labeled biohazard container. General trash such as food packaging, paper towels, and cardboard is not regulated medical waste.

Question 19Cleaning, Disinfection and Environmental Hygiene Practices

What is the purpose of testing a diluted disinfectant with a test strip?

  1. To verify the active ingredient is in range Correct answer.
  2. To find the room temperature the product needs
  3. To record how long the solution has been in the bucket
  4. To confirm the solution smells strong enough

Explanation

Test strips confirm that the concentration of active ingredient falls within the label's use range, since dispensing errors and product degradation can leave a solution too weak to be effective. Odor and appearance are not reliable indicators of concentration.

Question 20Cleaning, Disinfection and Environmental Hygiene Practices

A technician transfers cleaning solution from a large container into a spray bottle. What is required?

  1. Keep the bottle unlabeled to avoid mix-ups with other products
  2. Label the bottle with the product name and hazards Correct answer.
  3. Mark the bottle with the room number only
  4. Nothing, as long as the bottle is used the same day

Explanation

Secondary containers must carry the product name and the hazard information from the original label so that anyone using the bottle knows what it contains and how to use it safely. Unlabeled containers cause chemical misidentification and injury.

Question 21Cleaning, Disinfection and Environmental Hygiene Practices

A supervisor uses an ATP bioluminescence swab on a bed rail after terminal cleaning, and the reading is high. What does this result most likely indicate?

  1. A specific pathogen such as MRSA is present
  2. Organic soil or biomass remains on the surface Correct answer.
  3. The swab was past its expiration date
  4. The disinfectant contact time was too short

Explanation

ATP testing detects adenosine triphosphate from organic material and living cells, so a high reading signals that soil or biomass was left behind and the cleaning step needs improvement. It does not identify specific organisms or measure contact time directly.

Question 22Cleaning, Disinfection and Environmental Hygiene Practices

Why must a surface or device with visible biofilm be cleaned before it is disinfected?

  1. The matrix shields organisms from the disinfectant Correct answer.
  2. Disinfectants dissolve biofilm, so cleaning is unnecessary
  3. Biofilm lengthens contact time, so cleaning slows disinfection
  4. Biofilm is only cosmetic and does not affect disinfection

Explanation

Biofilm is a polysaccharide matrix that protects embedded microorganisms and prevents the disinfectant from reaching them, so mechanical cleaning is required to disrupt the film first. Disinfectants are not formulated to penetrate established biofilm.

Question 23Cleaning, Disinfection and Environmental Hygiene Practices

What precaution is required when entering a room vacated by a patient with suspected pulmonary tuberculosis to perform terminal cleaning?

  1. A surgical mask is enough because the patient has left
  2. Prop the door open to ventilate the room during cleaning
  3. No respiratory protection is needed after an hour
  4. A fit-tested N95 respirator and a closed door Correct answer.

Explanation

Tuberculosis is transmitted by the airborne route, so entry requires a fit-tested N95 or equivalent respirator and the door stays closed, with room clearance timed according to the facility's air exchange policy. A surgical mask does not provide adequate protection against airborne particles.

Question 24Cleaning, Disinfection and Environmental Hygiene Practices

Which practice supports control of Legionella in a building water system?

  1. Shutting off water to unused wings without flushing
  2. Lowering the hot water set point to save energy
  3. Adding bleach to the domestic water at every faucet
  4. Following the site water management plan Correct answer.

Explanation

A water management plan sets temperature ranges, flushing schedules for low-use outlets, and monitoring that together limit Legionella amplification in building water systems. Lowering hot water temperatures and abandoning outlets without flushing create conditions that favor growth.

Question 25Cleaning, Disinfection and Environmental Hygiene Practices

A surface is heavily soiled with feces. Why must the visible soil be removed before the disinfectant is applied?

  1. Removing soil is done only for appearance, not germ kill
  2. Disinfectants work faster when diluted by organic matter
  3. Organic matter can inactivate the disinfectant Correct answer.
  4. Soil keeps the disinfectant from evaporating too quickly

Explanation

Organic material such as feces, blood, and mucus can chemically inactivate many disinfectants and physically block contact between the chemical and the organisms. Cleaning to remove visible soil is therefore a prerequisite for effective disinfection, not a cosmetic step.

Question 26Cleaning, Disinfection and Environmental Hygiene Practices

A technician is preparing cleaning chemicals for a shift. Which practice prevents a hazardous chemical reaction?

  1. Choose products with the same label color so they are chemically compatible.
  2. Combine leftover products in one container to reduce storage space.
  3. Never mix chlorine bleach with ammonia-based or acid-based products. Correct answer.
  4. Add hot water to every mixture to speed up the reaction before use.

Explanation

Mixing sodium hypochlorite with acids releases chlorine gas, and mixing it with ammonia forms chloramines; both can cause severe respiratory injury. Products must be used only as directed on the label and never combined unless the manufacturer specifies it.

Question 27Cleaning, Disinfection and Environmental Hygiene Practices

A housekeeping aide finishes cleaning a room and has visible soil on both hands. What is the appropriate hand hygiene action?

  1. Wash with soap and water. Correct answer.
  2. Wipe the hands with a disinfectant surface wipe.
  3. Rinse the hands with warm water and dry with a paper towel.
  4. Apply an alcohol-based hand rub and rub until dry.

Explanation

Alcohol-based hand rubs are intended for hands that are not visibly soiled; soap and water physically removes soil along with transient organisms, including spores such as Clostridioides difficile that alcohol does not reliably kill.

Question 28Cleaning, Disinfection and Environmental Hygiene Practices

In what order should the surfaces of a patient room be cleaned?

  1. Dirtiest areas first, ending with the cleanest areas.
  2. In any order, as long as one cloth is used for the whole room.
  3. From highest to lowest, and from cleanest to dirtiest. Correct answer.
  4. Floor first, then walls, then high-touch items.

Explanation

Working from high to low and from clean to dirty keeps dust and soil from falling onto surfaces that have already been cleaned, and it keeps the cleaning tool from carrying contamination into cleaner areas. Floors are cleaned last for the same reason.

Question 29Cleaning, Disinfection and Environmental Hygiene Practices

How should clean linens and unused patient-care supplies be stored?

  1. In the soiled utility room, sealed inside plastic bags.
  2. On the floor of the storage closet, stacked against the back wall.
  3. In a clean, dry area off the floor and away from soiled items. Correct answer.
  4. In the patient's room, so they are readily available during care.

Explanation

Clean supplies must be kept in a clean, dry space, elevated off the floor and physically separated from soiled equipment and linen, so that they are not contaminated by splashes, pests, or contact with dirty items.

Question 30Cleaning, Disinfection and Environmental Hygiene Practices

A technician is halfway through a shift and the bucket of disinfectant is running low. What is the correct action?

  1. Discard the remaining solution and prepare a fresh bucket. Correct answer.
  2. Add fresh concentrate to the bucket until it reaches full strength.
  3. Top up with solution left over from a room cleaned earlier in the shift.
  4. Add water only, since the disinfectant is already dissolved in the bucket.

Explanation

A working solution loses potency as it picks up organic soil and evaporates, and its concentration can no longer be verified once it has been used. Facility policy and the product label set a use limit, after which the solution is discarded and a fresh batch is prepared.

Question 31Cleaning, Disinfection and Environmental Hygiene Practices

A sharps container in a patient room is about three-quarters full. What should the technician do?

  1. Close and replace the container, and start a new one. Correct answer.
  2. Press the contents down to make room for additional sharps.
  3. Keep filling it until the sharps reach the top, then seal it.
  4. Empty the contents into a larger container in the utility room.

Explanation

Sharps containers are closed and replaced when they reach about three-quarters full, which leaves room for safe closure and prevents needlesticks from protruding or being forced into an overfilled container.

Question 32Cleaning, Disinfection and Environmental Hygiene Practices

A norovirus outbreak has occurred on a patient unit. Which approach is most appropriate for disinfecting surfaces in the affected rooms?

  1. A chlorine-based disinfectant used at the concentration specified for norovirus. Correct answer.
  2. Soap and water alone, because norovirus is not affected by chemical disinfectants.
  3. A quaternary ammonium wipe with a one-minute contact time.
  4. An alcohol-based spray applied to all high-touch surfaces.

Explanation

Norovirus is a non-enveloped virus that survives many routine low-level disinfectants, including alcohol and standard quaternary ammonium concentrations. Chlorine-based products at the concentration specified on the label for norovirus are the recommended option, applied for the full contact time after cleaning.

Question 33Cleaning, Disinfection and Environmental Hygiene Practices

A technician prepares a diluted chlorine bleach solution for the shift. Which practice preserves its effectiveness?

  1. Keep a large batch on hand for a month so it is always ready to use.
  2. Store it in an open tray so fumes do not accumulate in the bucket.
  3. Prepare it fresh and use it within the facility's stated limit, generally 24 hours. Correct answer.
  4. Add a small amount of detergent to extend the shelf life of the solution.

Explanation

Hypochlorite loses activity over time, and degradation accelerates with heat, light, and organic soil. Solutions should be prepared fresh, kept in a closed labeled container away from light, and discarded within the time limit set by the facility or the label.

Question 34Cleaning, Disinfection and Environmental Hygiene Practices

A technician must clean a series of patient rooms, two of which house patients on contact precautions. In what order should the rooms be cleaned?

  1. Whichever rooms are nearest the exit, regardless of precaution status.
  2. Contact precaution rooms first, while supplies and energy are still fresh.
  3. Routine rooms first, then the contact precaution rooms. Correct answer.
  4. Isolation rooms alternating with routine rooms to save time and steps.

Explanation

Rooms are cleaned from the least contaminated to the most contaminated, so that organisms from a precaution room are not carried on equipment or clothing into rooms occupied by other patients. The cleaning cart is restocked and tools are disinfected before moving to the next room.

Question 35Cleaning, Disinfection and Environmental Hygiene Practices

A hospital adds ultraviolet-C disinfection to its terminal cleaning process. How should this technology be used?

  1. Before manual cleaning, so the light can penetrate soil deposits.
  2. As an adjunct to manual cleaning, never as a substitute for it. Correct answer.
  3. As a replacement for manual cleaning of high-touch surfaces.
  4. Only in operating rooms, because it damages surfaces elsewhere.

Explanation

Ultraviolet-C devices reduce organisms only on surfaces the light reaches, and soil or shadowing blocks the dose. Cleaning must come first to remove organic material, and the device is then used as a supplemental step in addition to standard cleaning and disinfection.

Question 36Cleaning, Disinfection and Environmental Hygiene Practices

After mopping a floor, how should reusable mop heads be handled?

  1. Stored in the bucket of used solution until the next shift.
  2. Rinsed in the dirty utility room sink and hung by the handle.
  3. Wrung out and stacked damp inside a closed cabinet.
  4. Laundered, dried completely, and stored head up. Correct answer.

Explanation

Mop heads hold moisture and soil and support rapid microbial growth if left damp. They are laundered, dried thoroughly before reuse, and stored with the head up so water drains away from the fibers.

Question 37Cleaning, Disinfection and Environmental Hygiene Practices

When should privacy curtains in a patient room be changed?

  1. Once a year, following the facility's scheduled maintenance calendar.
  2. At terminal cleaning, and whenever they are visibly soiled or contaminated. Correct answer.
  3. Every day during routine cleaning of every occupied patient room.
  4. Only when a patient or family member specifically asks staff for a change.

Explanation

Curtains are porous, frequently touched, and often overlooked, so they are changed at terminal cleaning and immediately when soiled or contaminated. Many facilities also set a periodic change interval as part of their written policy.

Question 38Cleaning, Disinfection and Environmental Hygiene Practices

A patient with Candida auris has been discharged. Which approach to terminal disinfection of the room is most appropriate?

  1. An EPA-registered sporicidal product effective against C. auris. Correct answer.
  2. Soap and water only, because C. auris is an enveloped virus.
  3. An alcohol wipe-down of every high-touch surface in the room.
  4. A standard quaternary ammonium product used at the label contact time.

Explanation

Candida auris is a yeast that persists on surfaces and is not reliably killed by routine quaternary ammonium products. Terminal disinfection requires an EPA-registered product with a claim against C. auris, such as a sporicidal agent, hydrogen peroxide, peracetic acid, or chlorine, used for the full contact time.

Question 39Cleaning, Disinfection and Environmental Hygiene Practices

Why should staff avoid discarding thickened liquids or beverages in patient room sinks?

  1. Sinks drain into greywater systems that are not permitted to receive organic waste.
  2. Sink drains and traps can become reservoirs that spread resistant organisms. Correct answer.
  3. Hospital sinks are intended only for hand hygiene and cannot accept other liquids.
  4. The trap will clog within days and require repeated plumbing repairs.

Explanation

Sink drains, traps, and the adjacent countertop are recognized reservoirs for gram-negative organisms such as Pseudomonas and carbapenem-resistant Enterobacterales, which can splash back onto hands and items. Waste fluids are discarded in a designated hopper or toilet, and sinks are reserved for hand hygiene.

Question 40Cleaning, Disinfection and Environmental Hygiene Practices

Which statement about processing hospital linens is accurate?

  1. Linen from patients on contact precautions must be double-bagged and labeled as contaminated.
  2. Hot-water washing at the specified temperature and time provides thermal disinfection. Correct answer.
  3. Linen must be sorted in the patient room and labeled with the patient's name for tracking.
  4. Cold-water washing with detergent is acceptable if an extra rinse cycle is added.

Explanation

Thermal disinfection is achieved by washing at a specified hot-water temperature for a defined time, or alternatively by a validated chemical disinfection process. All used linen is handled as contaminated with standard precautions and placed in a leak-resistant bag at the point of use.

Question 41Infection Prevention and Chain of Transmission

In the chain of infection, which link is defined as the place where an infectious agent normally lives, grows, and multiplies?

  1. Reservoir Correct answer.
  2. Mode of transmission
  3. Susceptible host
  4. Portal of exit

Explanation

The reservoir is the habitat in which an infectious agent normally lives and multiplies, such as humans, water, or contaminated equipment. The portal of exit and mode of transmission describe how the agent leaves the reservoir and travels to the next host, not where it resides.

Question 42Infection Prevention and Chain of Transmission

Standard precautions apply to which group of patients?

  1. Only patients placed in isolation rooms
  2. Only patients with a known bloodborne pathogen
  3. All patients, regardless of diagnosis Correct answer.
  4. Only patients with visible blood or body fluids

Explanation

Standard precautions are based on the principle that every patient may carry a transmissible organism, whether or not the infection is known or suspected. They therefore apply to all patients at all times and are supplemented by transmission-based precautions when a specific organism is identified or suspected.

Question 43Infection Prevention and Chain of Transmission

Which single practice is considered the most effective measure for preventing healthcare-associated infections?

  1. Wearing gloves for every patient contact
  2. Placing every patient in a private room at all times
  3. Performing hand hygiene at the appropriate moments Correct answer.
  4. Changing scrub uniforms every shift

Explanation

Hand hygiene is the single most effective intervention for interrupting the transmission of organisms on hands, which are the most common vehicle in healthcare settings. Other measures are useful adjuncts but do not substitute for correct timing and technique of hand hygiene.

Question 44Infection Prevention and Chain of Transmission

A patient with an infected wound colonized with methicillin-resistant Staphylococcus aureus is scheduled for hyperbaric therapy. Which precaution category is indicated?

  1. Airborne precautions
  2. Standard precautions only
  3. Contact precautions Correct answer.
  4. Droplet precautions

Explanation

Methicillin-resistant Staphylococcus aureus is transmitted primarily by direct and indirect contact with contaminated hands, surfaces, and equipment, so contact precautions are required in addition to standard precautions. Airborne and droplet precautions apply to organisms spread by respiratory aerosols or droplets.

Question 45Infection Prevention and Chain of Transmission

Which organism requires airborne infection isolation precautions?

  1. Staphylococcus aureus
  2. Mycobacterium tuberculosis Correct answer.
  3. Neisseria meningitidis
  4. Clostridioides difficile

Explanation

Mycobacterium tuberculosis is spread by droplet nuclei that remain infectious while suspended in air, so airborne precautions with a fit-tested respirator and negative-pressure room are required. Meningococcus and Clostridioides difficile are managed with droplet and contact precautions respectively.

Question 46Infection Prevention and Chain of Transmission

After drawing up an injectable medication, how should the used needle be handled?

  1. Recap it carefully using two hands, then place it in a biohazard bag
  2. Break the needle off the syringe and place it in a red bag
  3. Collect it in a cardboard box lined with a plastic bag
  4. Place it directly into a puncture-resistant sharps container Correct answer.

Explanation

Needles must never be recapped, bent, or broken by hand; they are deposited immediately into a puncture-resistant sharps container. Immediate disposal at the point of use removes the handling step that causes most needlestick injuries.

Question 47Infection Prevention and Chain of Transmission

Alcohol-based hand rub has poor activity against which of the following?

  1. Clostridioides difficile spores Correct answer.
  2. Candida albicans
  3. Methicillin-resistant Staphylococcus aureus
  4. Influenza A virus

Explanation

Alcohol denatures proteins and disrupts lipids but does not kill bacterial spores, so it is unreliable against Clostridioides difficile. For patients with known or suspected Clostridioides difficile infection, hand washing with soap and water is preferred because the mechanical action removes spores.

Question 48Infection Prevention and Chain of Transmission

A sharps container should be replaced when it is filled to approximately:

  1. Completely full
  2. One-half full
  3. One-quarter full
  4. Three-quarters full Correct answer.

Explanation

Containers are closed and replaced when they reach about three-quarters capacity, which leaves room for safe insertion and prevents sharps from protruding. Overfilling creates a risk of injury when the container is handled or closed.

Question 49Infection Prevention and Chain of Transmission

A patient with suspected influenza must be moved to the hyperbaric suite. What is the most appropriate action during transport?

  1. Place an N95 respirator on the patient, if tolerated
  2. Postpone transport until the fever has resolved
  3. Transport the patient without a mask and notify receiving staff
  4. Place a surgical mask on the patient during transport Correct answer.

Explanation

For droplet precautions, the patient wears a surgical mask in transit to contain respiratory droplets, and healthcare personnel wear a mask plus eye protection for close contact. Source control during movement is the key step that limits contamination of corridors and common areas.

Question 50Infection Prevention and Chain of Transmission

Which statement about N95 respirators is correct?

  1. Respirators may be shared between staff after being wiped with alcohol
  2. A surgical mask worn over the respirator removes the need for a seal check
  3. Fit testing is required only once, at the time of hire
  4. A user seal check is performed each time the respirator is donned Correct answer.

Explanation

A user seal check confirms that the respirator is seated correctly on the face and is repeated at every donning, because small gaps defeat the filtration. Fit testing is repeated periodically and after changes in facial features or equipment, and respirators are assigned to individuals.