Infection Control and Safety Practice Questions for CNA Certification

Introduction

Infection control and safety represent one of the most critical and heavily tested domains in the Certified Nursing Assistant (CNA) examination, comprising 18-39% of the total exam content. As a CNA, you serve as the first line of defense against healthcare-associated infections, making your understanding of proper infection prevention protocols absolutely essential for patient safety and your own protection. The ability to implement standard precautions, utilize personal protective equipment (PPE) correctly, and maintain proper hand hygiene techniques directly impacts patient outcomes and can prevent the spread of dangerous pathogens in healthcare settings. Healthcare facilities depend on CNAs to consistently follow infection control procedures, as even minor lapses can lead to serious consequences including patient harm, facility outbreaks, and legal liability. This topic area is not only fundamental to passing your certification exam but also forms the foundation of safe nursing practice throughout your career. The questions in this practice set will test your knowledge of isolation procedures, proper disposal of contaminated materials, recognition of infection risks, and emergency safety protocols. Mastering these concepts ensures you can protect vulnerable patients, maintain a safe work environment, and demonstrate the professional competence expected of certified nursing assistants. Your success in this domain directly correlates with your ability to provide quality patient care while minimizing infection transmission risks. The clinical skills portion of your CNA exam will also heavily emphasize proper infection control techniques, making thorough preparation in this area essential for comprehensive exam success. Understanding these principles will serve you well beyond the exam, as infection control remains a daily priority in all healthcare settings where CNAs practice.

Practice Questions

Question 1: When should a CNA perform hand hygiene?

1. Only before patient contact
2. Only after patient contact
3. Before and after patient contact, and after removing gloves
4. Only when hands are visibly soiled

Correct Answer: C) Before and after patient contact, and after removing gloves

Explanation: Hand hygiene is the single most important measure to prevent healthcare-associated infections. CNAs must perform hand hygiene before patient contact to prevent introducing pathogens to the patient, after patient contact to prevent spreading pathogens to other patients or surfaces, and after removing gloves because gloves can have microscopic holes or become contaminated during removal. This follows the “5 Moments for Hand Hygiene” guidelines established by the World Health Organization.

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Question 2: Which type of personal protective equipment (PPE) should be put on FIRST?

1. Gloves
2. Mask or respirator
3. Gown
4. Eye protection

Correct Answer: C) Gown

Explanation: The correct sequence for donning PPE is: gown first, then mask/respirator, then eye protection, and finally gloves. The gown is put on first because it covers the largest surface area and provides the foundation for other PPE. Gloves are always put on last because they go over the cuff of the gown and are most likely to become contaminated during patient care.

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Question 3: A patient is placed on contact precautions. What does this mean for the CNA?

1. The patient can only be touched with bare hands
2. Gown and gloves must be worn for all patient contact
3. Only gloves are required
4. No special precautions are needed

Correct Answer: B) Gown and gloves must be worn for all patient contact

Explanation: Contact precautions require the use of gown and gloves for all patient contact and contact with the patient’s environment. This prevents transmission of pathogens that spread through direct contact with the patient or contaminated surfaces. The gown protects clothing and skin, while gloves protect hands from contamination.

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Question 4: How long should alcohol-based hand sanitizer be rubbed on hands?

1. 5 seconds
2. 10 seconds
3. 15-20 seconds until hands are dry
4. 30 seconds

Correct Answer: C) 15-20 seconds until hands are dry

Explanation: Alcohol-based hand sanitizer should be applied to all surfaces of the hands and rubbed for 15-20 seconds until the hands are completely dry. This contact time is necessary for the alcohol to effectively kill microorganisms. The sanitizer should not be wiped off but allowed to air dry completely.

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Question 5: Which of the following items should be disposed of in a red biohazard bag?

1. Empty medication bottles
2. Used tissues from a patient with a cold
3. Blood-soaked gauze
4. Regular trash from patient rooms

Correct Answer: C) Blood-soaked gauze

Explanation: Red biohazard bags are used for regulated medical waste that is contaminated with blood or other potentially infectious materials. Blood-soaked gauze poses a risk of bloodborne pathogen transmission and must be disposed of as regulated medical waste. Regular tissues, empty medication bottles, and general trash do not require biohazard disposal unless contaminated with blood or body fluids.

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Question 6: When caring for a patient with tuberculosis, which type of mask should the CNA wear?

1. Surgical mask
2. N95 respirator or higher
3. Cloth mask
4. No mask is needed

Correct Answer: B) N95 respirator or higher

Explanation: Tuberculosis is transmitted through airborne droplet nuclei, requiring airborne precautions. An N95 respirator or higher level of respiratory protection is required because it can filter out particles as small as 0.3 microns. Surgical masks are not adequate for airborne precautions as they do not provide a tight seal and cannot filter small airborne particles effectively.

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Question 7: What is the most appropriate action if a CNA accidentally sticks themselves with a used needle?

1. Apply pressure and continue working
2. Wash the wound, report immediately to supervisor, and seek medical evaluation
3. Apply a bandage and finish the shift
4. Only report if the patient has a known infection

Correct Answer: B) Wash the wound, report immediately to supervisor, and seek medical evaluation

Explanation: Needlestick injuries pose a serious risk of bloodborne pathogen transmission including HIV, Hepatitis B, and Hepatitis C. The wound should be immediately washed with soap and water, the incident must be reported to the supervisor immediately, and medical evaluation should be sought promptly. Post-exposure prophylaxis may be necessary and is most effective when started quickly.

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Question 8: Which cleaning solution is most effective for disinfecting surfaces contaminated with Clostridium difficile (C. diff)?

1. Alcohol-based disinfectant
2. Bleach solution (sodium hypochlorite)
3. Hydrogen peroxide
4. Soap and water only

Correct Answer: B) Bleach solution (sodium hypochlorite)

Explanation: C. diff forms spores that are resistant to alcohol and many other disinfectants. Bleach solution (sodium hypochlorite) is one of the few disinfectants effective against C. diff spores. A 1:10 dilution of household bleach is typically recommended for environmental disinfection in areas where C. diff patients are cared for.

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Question 9: When should standard precautions be used?

1. Only with patients who have known infections
2. Only with patients in isolation
3. With all patients at all times
4. Only when handling blood

Correct Answer: C) With all patients at all times

Explanation: Standard precautions are the foundation of infection prevention and should be used with all patients at all times, regardless of their infection status. This approach assumes that all patients may harbor infectious agents, even if not diagnosed. Standard precautions include hand hygiene, use of PPE when indicated, safe injection practices, and proper handling of contaminated equipment.

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Question 10: What is the correct procedure for removing contaminated gloves?

1. Pull off from the fingertips
2. Grasp the outside of one glove and peel off, then slide fingers under the remaining glove to remove
3. Cut them off with scissors
4. Rinse with water first, then remove

Correct Answer: B) Grasp the outside of one glove and peel off, then slide fingers under the remaining glove to remove

Explanation: Proper glove removal prevents contamination of hands. First, grasp the outside of one glove near the wrist and peel it off, turning it inside out. Hold the removed glove in the remaining gloved hand. Then slide the fingers of the ungloved hand under the wrist of the remaining glove and peel it off over the first glove, turning it inside out. This technique ensures that the contaminated surfaces never touch the skin.

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Question 11: A patient’s room requires airborne precautions. What type of room is required?

1. Any private room
2. A private room with negative air pressure
3. A semi-private room
4. Room type doesn’t matter

Correct Answer: B) A private room with negative air pressure

Explanation: Airborne precautions require a private room with negative air pressure relative to surrounding areas. This prevents contaminated air from flowing out of the room. The room should have at least 6-12 air changes per hour and air should be exhausted directly outside or filtered through HEPA filters before recirculation.

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Question 12: Which body fluid requires the same precautions as blood?

1. Saliva
2. Sweat
3. Cerebrospinal fluid
4. Urine (unless visibly bloody)

Correct Answer: C) Cerebrospinal fluid

Explanation: Cerebrospinal fluid is considered a potentially infectious body fluid that requires the same precautions as blood because it can transmit bloodborne pathogens. Other body fluids requiring blood precautions include synovial fluid, pleural fluid, pericardial fluid, peritoneal fluid, and amniotic fluid. Saliva (except in dental procedures), sweat, and urine (unless visibly bloody) are not considered potentially infectious unless contaminated with blood.

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Question 13: How often should isolation gowns be changed?

1. Once per shift
2. Between each patient contact
3. Only when visibly soiled
4. Every 4 hours

Correct Answer: B) Between each patient contact

Explanation: Isolation gowns should be changed between patient contacts to prevent cross-contamination. Even if the gown appears clean, it may be contaminated with microorganisms that are not visible. Using the same gown for multiple patients defeats the purpose of isolation precautions and can spread infections between patients.

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Question 14: What is the minimum time for washing hands with soap and water?

1. 10 seconds
2. 15 seconds
3. 20 seconds
4. 30 seconds

Correct Answer: C) 20 seconds

Explanation: Hands should be washed with soap and water for at least 20 seconds to effectively remove microorganisms. This includes time for wetting hands, applying soap, scrubbing all surfaces (including between fingers and under nails), rinsing thoroughly, and drying with a clean towel. The mechanical action of scrubbing combined with adequate time is essential for effective hand hygiene.

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Question 15: When entering a room with droplet precautions, the CNA should:

1. Wear only gloves
2. Wear a surgical mask within 3 feet of the patient
3. Wear an N95 respirator
4. No special equipment is needed

Correct Answer: B) Wear a surgical mask within 3 feet of the patient

Explanation: Droplet precautions require wearing a surgical mask when within 3 feet of the patient because respiratory droplets typically travel only short distances (usually less than 3 feet) before falling to the ground. Unlike airborne precautions, droplet precautions do not require an N95 respirator because the particles are larger and do not remain suspended in air for long periods.