Different Types of Autoclaves: Full Detailed

What Is an Autoclave?

An autoclave is a sterilization device that uses high-temperature saturated steam under pressure to destroy all microorganisms, including:

• Bacteria
• Viruses
• Fungi
• Mycobacteria
• Bacterial spores

Autoclaves are considered the gold standard for sterilization because they are reliable, effective, and environmentally safe when used correctly. 

In this complete guide by Aarogyaa Bharat, we explain:

• What an autoclave is and how it works
• Autoclave classification by Class (B, N, S)
• Autoclave classification by design and application
• Use-case mapping for hospitals, labs, and clinics
• How to choose the right autoclave for your facility

How Autoclaves Are Classified

Autoclaves can be broadly classified in two major ways:

1. By sterilization class (Class B, Class N, Class S)
2. By design and application (gravity, vacuum, tabletop, vertical, etc.)

Understanding both classifications helps in choosing the right equipment for your workflow.

Classification 1: Types of Autoclave by Class (EN 13060 Standard)

1. Class B Autoclave (Most Advanced)

Class B autoclaves are the highest and most versatile category of steam sterilizers.

How it works

• Uses pre-vacuum and post-vacuum cycles
• Removes air completely before steam injection
• Ensures excellent steam penetration into complex loads

What it can sterilize

• Wrapped and unwrapped instruments
• Hollow instruments (Type A & B)
• Porous loads
• Textile packs

Where it is used

• Hospitals
• CSSD departments
• Dental clinics
• Surgical centres

Advantages

• Highest sterilization assurance
• Suitable for all load types
• Meets international standards (NABH, JCI)

Limitations

• Higher cost
• Requires trained staff and maintenance

Best choice for facilities handling critical instruments

2. Class N Autoclave (Basic Sterilization)

Class N autoclaves are designed for simple, unwrapped solid instruments.

How it works

• Uses gravity displacement
• No vacuum phase

What it can sterilize

• Solid, unwrapped instruments only

Cannot sterilize:

• Wrapped instruments
• Hollow instruments
• Porous loads

Where it is used

• Small clinics
• Tattoo studios
• Simple outpatient setups

Advantages

• Affordable
• Easy to operate

Limitations

• Limited applications
• Not suitable for advanced medical procedures

Not recommended for hospitals or dental clinics handling complex instruments

3. Class S Autoclave (Specialized Use)

Class S autoclaves fall between Class B and Class N.

How it works

• Limited vacuum cycles
• Sterilization capability depends on manufacturer specification

What it can sterilize

• Specific wrapped or hollow instruments (as defined by manufacturer)

Where it is used

• Specialty clinics
• Facilities with known, limited instrument types

Advantages

• More flexible than Class N
• Lower cost than Class B

Limitations

• Not universal
• Requires careful load compatibility checks

Classification 2: Types of Autoclaves by Design & Application

1. Gravity Displacement Autoclave

• Steam displaces air naturally
• Simple and cost-effective

Best for:
Laboratories, media sterilization, basic instruments

2. Pre-Vacuum (High-Vacuum) Autoclave

• Uses vacuum pump to remove air
• Superior steam penetration

Best for:
Hospitals, CSSD, wrapped surgical instruments

3. Tabletop / Benchtop Autoclave

• Compact and space-saving
• Often Class B or S

Best for:
Dental clinics, small labs, outpatient centers

4. Vertical Autoclave

• Top-loading design
• Ideal for liquids and culture media

Best for:
Laboratories, pharmaceutical units

5. Horizontal Autoclave

• Front-loading, large chamber
• High throughput

Best for:
Hospitals, large CSSD units

Choosing the Right Autoclave for Your Facility

Ask These Key Questions

1. What type of instruments are being sterilized?
• Solid only → Class N
• Hollow / wrapped → Class B
2. Volume of sterilization?
• Low → Tabletop
• High → Horizontal / CSSD autoclave
3. Regulatory requirements?
• NABH / JCI → Class B recommended
4. Available space & utilities?
• Small clinic → Benchtop
• Hospital → Floor-mounted systems

Comparison Table: Autoclave Types at a Glance

Why Aarogyaa Bharat Is Your Trusted Partner for Autoclaves

At Aarogyaa Bharat, we help healthcare and laboratory facilities choose the right sterilization solution, not just any autoclave.

We offer:

• Class B, S, and N autoclaves
• Tabletop, vertical, and CSSD systems
• Expert guidance based on your use case
• Reliable after-sales and service support

Our mission is to ensure safe, compliant, and efficient sterilization across India.

Conclusion

Understanding the different types of autoclaves is essential for making the right sterilization investment. While Class N autoclaves may suit basic needs, Class B autoclaves provide the highest level of safety, flexibility, and compliance - making them the preferred choice for modern healthcare facilities.

When sterilization matters, choosing the right autoclave makes all the difference.