The Big Picture
Asepsis involves reducing or eliminating microorganisms that could cause illness. There are two levels of asepsis: medical asepsis and surgical asepsis.
The biggest idea to remember is that clean and sterile do not mean the same thing. Clean means there are no visible contaminants. Sterile means there are no microbes or their spores.
Look for Nova Scotia CCA Notes throughout this page for current provincial guidance.
Quick tip: Tap, click, or press Enter on any term with a dotted underline and an ⓘ icon to see its plain-English definition.
Start Here If You’re Overwhelmed
Focus on these core ideas:
- Asepsis means reducing or eliminating potential pathogens.
- Medical asepsis reduces pathogens and helps prevent their spread.
- Hand hygiene is the most important part of medical asepsis for preventing the spread of illness.
- Clean means no visible contaminants. Contaminated means exposure to pathogens has occurred.
- Sterile means free from all microbes and their spores.
- Surgical asepsis keeps equipment and supplies free from all microbes and their spores.
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Course Notes: Key Ideas You Need to Know
What Is Asepsis?
Asepsis is the practice of reducing or eliminating potential pathogens. Pathogens include bacteria, viruses, fungi, and parasites.
There are two levels of asepsis:
- Medical asepsis
- Surgical asepsis
These two levels have different goals.
Medical Asepsis
Key fact: The goal of medical asepsis is to exclude all pathogenic microorganisms.
Medical asepsis, also called clean technique, includes practices that:
- reduce the number of pathogens
- prevent pathogens from spreading from one person to another
- prevent pathogens from spreading from one place to another
Medical asepsis is the most commonly used level of asepsis. All health care workers should practise it because they have an important role in preventing infection from spreading.
Nova Scotia CCA Note
Sorrentino’s Canadian Textbook for the Support Worker, 5th Edition teaches the general principles of medical asepsis. Nova Scotia’s current CCA Occupational Standards of Practice add specific expectations for how a CCA takes part in infection control.
In Nova Scotia, a CCA identifies infection-control and environmental risks, applies personal protective equipment (PPE), and uses appropriate isolation precautions and infection-control practices. The CCA also maintains the safety and cleanliness of the care setting according to the care plan, legislation , employer policies , acts, and regulations . (novascotiacca.ca)
Why this matters in Nova Scotia: The current standards help define CCA practice and are used as a foundation for the provincial CCA Certification Exam. Connect infection prevention with the care plan and workplace requirements when studying the CCA role. (novascotiacca.ca)
Official source: Continuing Care Assistant Occupational Standards of Practice (CCA OSoP)
Last checked: September 12, 2026
Hand Hygiene
Hand hygiene means cleaning the hands.
Hand hygiene is the most important part of medical asepsis that health care workers practise to help prevent illnesses caused by pathogens from spreading.
What Does Clean Mean?
In most health care units, clean describes something that has no visible contaminants.
For example, washed hands or washed clothing may be described as clean. Clean does not mean sterile.
Clean gloves are different from sterile surgical gloves. Clean gloves are changed between clients.
What Does Contaminated Mean?
Contaminated, or unclean, describes something that has been exposed to pathogens.
The contamination does not need to be visible. Soiled bed linen is one example of something considered contaminated.
Contamination means exposure to microorganisms, including pathogens.
What Does Sterile Mean?
Sterile means free from all microbes, including:
- pathogens
- nonpathogens
- microbial spores
A clean environment is therefore different from a sterile environment.
Something may be clean because it has no visible contamination, but sterile means microbes and their spores are absent.
Surgical Asepsis
Surgical asepsis, also called sterile technique, includes practices that keep equipment and supplies free from all microbes and their spores.
Surgical asepsis aims to exclude all microorganisms and their spores. This differs from medical asepsis, which focuses on pathogenic microorganisms and reducing their number and spread.
During surgery and invasive procedures, microbes cannot be present because infection is a risk. Operating rooms and instruments inserted into the body must therefore be sterile.
What Is Sterilization?
Sterilization is the process of destroying all microbes.
This includes:
- pathogens
- nonpathogens
- their spores
Medical Asepsis vs. Surgical Asepsis
| Medical Asepsis | Surgical Asepsis |
|---|---|
| Also called clean technique | Also called sterile technique |
| Reduces the number of pathogens | Keeps equipment and supplies free from all microbes |
| Prevents pathogens from spreading | Excludes microorganisms and their spores |
| Hand hygiene is the most important part of medical asepsis | Operating rooms and instruments inserted into the body must be sterile for surgery or invasive procedures |
Clean, Contaminated, and Sterile
| Term | What It Means |
|---|---|
| Clean | No visible contaminants |
| Contaminated | Exposed to pathogens, even when contamination is not visible |
| Sterile | Free from all microbes and their spores |
The key difference is the standard being described. Clean focuses on visible contamination. Sterile means microorganisms and spores are absent.
Exam Clue Words
- Most important: Hand hygiene is the most important part of medical asepsis that health care workers practise to prevent the spread of illnesses caused by pathogens.
- Should: Medical asepsis should be practised by all health care workers.
- Must: Operating rooms and instruments inserted into the body must be sterile during surgery or invasive procedures.
Fast Review
Keep the main differences clear. Medical asepsis focuses on reducing pathogens and their spread. Surgical asepsis focuses on keeping equipment and supplies free from all microbes and spores.
- Asepsis means reducing or eliminating potential pathogens.
- The two levels are medical asepsis and surgical asepsis.
- Medical asepsis is also called clean technique.
- Medical asepsis reduces pathogens and helps prevent their spread.
- Hand hygiene is the most important part of medical asepsis for preventing the spread of illness.
- Clean means no visible contaminants.
- Contaminated means exposed to pathogens, even when contamination is not visible.
- Sterile means free from pathogens, nonpathogens, and their spores.
- Surgical asepsis is also called sterile technique.
- Sterilization destroys all microbes, including their spores.
Final Pep Talk
The main challenge here is separating words that sound similar. Focus on the differences between clean, contaminated, and sterile, then connect medical asepsis with clean technique and surgical asepsis with sterile technique.