Fume Hood vs. Biosafety Cabinet: What’s the Difference?

Key Differences Between a Fume Hood and a Biosafety Cabinet

What a Chemical Fume Hood Does (and Doesn’t Do)

Chemical fume hoods are exhaust devices designed to capture and remove chemical vapors, fumes, and particulates generated during laboratory procedures.

Room air is drawn through the sash opening, across the work surface, and exhausted to the outdoors via the building exhaust system. Containment performance is verified through ANSI/ASHRAE 110 testing, which evaluates how effectively the hood prevents contaminants from escaping into the laboratory.

Important Limitation: Fume hoods do not provide product sterility, do not use HEPA filtration, and must not be used for biological product protection.

ANSI/ASHRAE 110-2016 (RA2025): Why It Matters

ANSI/ASHRAE 110 is a performance-based standard that defines how fume hood containment is tested, both at the factory and in the field.

Unlike prescriptive standards, it does not dictate airflow rates. Instead, it evaluates:

• Hood aerodynamic design

• Exhaust system stability

• Laboratory room airflow

• User work practices

This standard provides a quantitative and qualitative method for commissioning new fume hoods and verifying performance over time.

For laboratories in Malaysia, compliance with ASHRAE 110 is a critical part of chemical safety management.

When Should You Use a Chemical Fume Hood?

Use a fume hood when your work involves:

• Toxic or corrosive chemicals

• Volatile solvents

• Acid digestion

• Chemical synthesis

• Processes producing hazardous fumes or vapors

A fume hood is the correct containment device for chemical hazards, not biological materials

What a Biosafety Cabinet Does (and Doesn’t Do)

A biosafety cabinet is an enclosed, ventilated laboratory device designed to protect:

• Personnel

• Product

• The environment

BSCs achieve this through inward airflow, HEPA filtration, and laminar downflow, which prevents cross-contamination and contains biological aerosols.

Biosafety cabinets are classified into three main classes, each offering different levels of protection.

Biosafety Cabinet Classes Explained

Class I Biosafety Cabinets

• Protect personnel and environment only

• No product protection

• Commonly used for:

  • Non-sterile drug compounding

  • Animal cage dumping

  • Tissue homogenization

  • Aerosol-generating equipment

Class II Biosafety Cabinets

All Class II BSCs use internal motor blowers to create personnel inflow and HEPA-filtered laminar downflow for product protection.

Type A1 and A2

• Recirculate ~70% of air through HEPA filters

• Exhaust ~30%

• Type A2 operates at higher inflow velocity (100 fpm)

• May be canopy-connected to facility exhaust

• Application for Type A1: Standard low risk microbiological and non-volatile biological samples

• Application for Type A2: Cell culture, bacterial and viral work at BSL-1 or BSL-2, sample preparation

Type B1

• Hard-ducted to building exhaust

• Exhausts ~70% of air

• Designed for limited volatile chemical use alongside biological work

• Requires exhaust interlocks and alarms

• Application: Microbiology work involving low levels of volatile chemicals or radionuclides

Type B2

• Total exhaust (100%)

• No air recirculation

• Provides the highest chemical safety among Class II cabinets

• Requires reliable exhaust and emergency power

• Application: Workflow with high levels of volatile toxic chemical, radionuclide components and biohazardous chemicals

Type C1

• Hybrid design exhausting ~60%

• Increased mechanical complexity

• Spill cleanup and contamination control can be more challenging

• In many cases, A2 or B1/B2 offers better long-term reliability

• Application: Most BSL-1 and BSL-2 biological work, GMP or R&D labs where protocols may evolve

Can a Biosafety Cabinet Be Used for Chemicals?

This is a critical safety question.

HEPA filters capture particulates and biological agents, but do not remove chemical vapors or gases.

Therefore:

• Only canopy-connected A1, A2, or C1 cabinets, or

• Hard-ducted B1 or B2 cabinets

may be used for limited volatile chemical work, and only after a documented risk assessment.

Using a standard biosafety cabinet for solvent work without proper exhaust can increase exposure risk.

Common Mistakes & Operational Guidance

• Critical Safety Interlocks

• Hard-ducted B1 and B2 cabinets must include exhaust interlocks

• Internal blowers must shut down automatically if exhaust airflow fails

• Exhaust systems should be connected to emergency power

• These safeguards prevent hazardous air from being forced out of the front opening during system failure.

⚠️ Not sure which cabinet configuration is compliant for your lab?
Gaia Science (M) Sdn Bhd supports EHS managers, lab planners, and QA/QC teams across Malaysia in selecting NSF-certified NuAire containment systems.

📞 Speak to a specialist: 03-8065 3889 or write to us at marketing@gaiascience.com.my

Class III Biosafety Cabinets

Class III BSCs provide maximum containment for work with highly infectious agents (BSL-4).

They are:

• Gas-tight enclosures

• Operated under negative pressure

• Equipped with double HEPA-filtered exhaust

• Manipulated using heavy-duty attached gloves

These cabinets offer the highest level of personnel and environmental protection.

NSF/ANSI 49: The Gold Standard for Biosafety Cabinets

NSF/ANSI 49 governs:

• Design and construction

• Performance testing

• Field certification

• Biological containment validation

Cabinets certified to NSF/ANSI 49 meet minimum requirements for personnel, product, and environmental protection, durability, cleanability, and reliability.

Conclusion: Choosing the Right Containment System

Fume hoods and biosafety cabinets serve different safety purposes:

• Fume hoods protect users from chemical vapors

• Biosafety cabinets protect users, products, and the environment from biological hazards

Selecting the correct system is essential for laboratory safety, regulatory compliance, and long-term operational success.

Contact Gaia Science (M) Sdn Bhd

As the sole authorised distributor for NuAire in Malaysia, Gaia Science (M) Sdn Bhd provides comprehensive technical support for laboratory containment selection, installation planning, and compliance requirements.

Still unsure which system fits your laboratory’s risk assessment?

Our trained and certified specialists are ready to guide you — from application review and standards compliance to long-term safety.

Phone / WhatsApp: 03-8065 3889
Email: marketing@gaiascience.com.my

Disclaimer: Content on this page is based on technical information published by NuAire and is provided as general guidance for users.