DANB DANB Chemical Disinfectants & Sterilants 1 — Questions and Answers
Question 1: Which organization is responsible for registering disinfectants used in dental settings in the United States?
- CDC
- EPA (Correct answer)
- OSHA
- FDA
Correct answer: EPA
The Environmental Protection Agency (EPA) registers all disinfectants and sterilants used in dental and healthcare settings in the U.S.
Question 2: What are the three levels of disinfection recognized in dental infection control?
- Minimal, moderate, and maximum
- Low, intermediate, and high (Correct answer)
- Basic, standard, and advanced
- Primary, secondary, and tertiary
Correct answer: Low, intermediate, and high
Disinfection is categorized into three levels—low, intermediate, and high—based on the spectrum of microorganisms the disinfectant can kill.
Question 3: Which level of disinfection is required to kill all microorganisms including Mycobacterium tuberculosis but NOT necessarily high numbers of bacterial spores?
- Low-level
- Intermediate-level (Correct answer)
- High-level
- Chemical sterilization
Correct answer: Intermediate-level
Intermediate-level disinfection kills most microorganisms including M. tuberculosis and fungi but may not eliminate high numbers of resistant bacterial spores.
Question 4: Glutaraldehyde used as a liquid chemical sterilant typically requires a minimum contact time of how long?
- 10 minutes
- 30 minutes
- 6–10 hours (Correct answer)
- 24 hours
Correct answer: 6–10 hours
To achieve sterilization, glutaraldehyde must remain in contact with instruments for 6–10 hours depending on the product formulation.
Question 5: Which chemical agent is classified as a high-level disinfectant and chemical sterilant in dentistry?
- 70% isopropyl alcohol
- Quaternary ammonium compound
- 2% glutaraldehyde (Correct answer)
- Phenolic compound
Correct answer: 2% glutaraldehyde
2% glutaraldehyde is an EPA-registered high-level disinfectant and chemical sterilant capable of killing all microorganisms including spores with prolonged exposure.
Question 6: Quaternary ammonium compounds (quats) are classified as what level of disinfectant?
- High-level
- Intermediate-level
- Low-level (Correct answer)
- Chemical sterilant
Correct answer: Low-level
Quaternary ammonium compounds are low-level disinfectants effective against some bacteria and lipid-enveloped viruses but not against mycobacteria, bacterial spores, or non-enveloped viruses.
Question 7: Which level of disinfectant is most appropriate for clinical contact surfaces in dental operatories?
- Low-level only
- Intermediate-level or higher (Correct answer)
- Chemical sterilant only
- High-level only
Correct answer: Intermediate-level or higher
CDC guidelines recommend intermediate-level disinfectants (EPA-registered hospital disinfectants with a tuberculocidal claim) for clinical contact surfaces in dental settings.
DANB DANB Chemical Disinfectants & Sterilants 1
Which organization is responsible for registering disinfectants used in dental settings in the United States?