Biological safety cabinets (BSCs)—sometimes simply called biosafety cabinets—are enclosed hoods or workspaces that vent hazardous biological materials, pathogens, and contaminants to keep them from coming into contact with people, work samples, and the environment. A HEPA filter is generally used to pull dangerous particles out of the contaminated air. Three classes of biosafety cabinets are available, depending on the level of protection required and the danger posed by the materials being handled.
Biosafety Cabinet Classification
The three biosafety cabinet classifications are:
This is the lowest level of BSC protection available. Class 1 biosafety cabinets protect people and the environment, but they don’t shield samples from contamination and should never be used if there is a risk of airborne contamination. These cabinets are appropriate for low-to-moderate risk biological agents, or those rated at biosafety levels 1, 2, and 3.
Class 2 biological safety cabinets protect people, the environment, and work samples. These biosafety cabinets are divided into four subtypes—A1, A2, B1, and B2–depending on their airflow speeds and exhaust systems. Like Class 1 BSCs, Class 2 BSCs are appropriate for biosafety levels 1, 2, and 3. Class 2 BSCs feature dual or triple HEPA filter systems to safely handle air exiting the contained unit.
Class 3 biosafety cabinets provide the highest level of protection possible. They protect people, the environment, and work samples, and they can be used with extremely infectious biological agents. Class 3 BSCs are fully-sealed, airtight cabinets that put a comprehensive physical barrier between workers and the substances they’re handling.
Long, heavy duty rubber gloves stretch from the outside to the inside of the cabinet, allowing lab work to be conducted without touching dangerous materials. Class 3 biological safety cabinets are the only BSCs appropriate for working with biosafety level 4 materials.
The four biosafety levels are defined by the Centers for Disease Control (CDC) as follows:
- Biosafety Level 1: Level 1 microbes aren’t known to cause disease in healthy adults and pose a minimal risk for both workers and the environment. No special containment equipment is required for level 1 projects, and the work can be conducted at a standard lab bench.
- Biosafety Level 2: Level 2 microbes are moderately pathogenic and can cause disease. Labs working with level 2 materials have self-closing doors and require workers to wear protective equipment.
- Biosafety Level 3:Level 3 microbes can be transmitted through the air and inhaled. They can cause serious and sometimes life-threatening diseases. Labs working on level 3 projects have self-closing and self-locking doors. Exhaust is never recirculated, but instead replaced by fresh outside air. These labs require workers to wear protective equipment, and they may require respirators as well.
- Biosafety Level 4: Level 4 microbes are highly contagious and extremely life-threatening. In many cases there aren’t treatments available for those who become infected. Level 4 projects require maximum containment and protection at all times. Workers must change clothes upon entering the lab, and they must shower and decontaminate all materials before leaving the protected area.
Biosafety Cabinet Testing / Certification
Industries that rely on biological safety cabinets include healthcare, biomedical labs, and other research environments. The National Science Foundation International tests all biosafety cabinets to make sure they meet the minimum standards for:
- Design, construction, and performance
- Effective protection of people, products, and the environment
- Reliability, durability, and cleanability
- Noise, light, and vibration control
- Electrical safety
All biosafety cabinets must also receive field certification from an independent organization.
Plastic Design, Inc. Capabilities
Plastic Design, Inc. has more than 40 years of experience making products for use in biomedical, pharmaceutical, and animal research applications. Our cabinets are available with a wide range of hood types, including sliding sash, angled open front, fully isolated, tabletop, stand alone, and vertical laminar flow hoods. We’re ISO 9001:2015-certified for quality assurance in our custom plastic products and filtration systems for biomedical and pharmaceutical uses.