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5 Factors To Consider When Choosing a Biological Safety Cabinet

In the field of science, working with hazardous biological agents is a common practice. To ensure the safety of both researchers and the environment, biological safety cabinets (BSCs) are essential. These specialized enclosures provide a controlled environment that minimizes the risk of exposure to infectious materials and protection for the product, operator, and the environment.

When selecting a biological safety cabinet, there are five key factors that must be carefully considered to ensure optimal protection and efficient operation.

1. Level of Protection (Biosafety Level)

When selecting a biological safety cabinet (BSC), the most critical factor to consider is the level of protection it provides. This is determined by the biosafety level (BSL) required for the specific microorganisms being handled. BSLs range from BSL-1 (low risk) to BSL-4 (high risk).

It is essential to carefully assess the level of protection required based on your specific application and your laboratory’s safety protocols. Selecting the appropriate BSC ensures compliance with regulatory standards and minimizes the risk of exposure to infectious agents, safeguarding the health and safety of laboratory personnel.

Key Protection Considerations

  • Biosafety levels range from BSL-1 (low risk) to BSL-4 (high risk)
  • The level of protection required depends on the biosafety level of microorganisms and if fume protection is needed
  • Class II, Type A2 cabinets provide BSL-1, 2, 3 protection
  • Class II, Type B2 cabinets are ducted units that can be used for applications that also require protection from fumes
  • Class III cabinets provide BSL-4 protection

2. Certification

Certification is another important factor to consider when choosing a biological safety cabinet. In accordance with OSHA Laboratory Safety Biosafety Cabinets (BSCs), all biosafety cabinets should be certified when installed, whenever they are moved, and at least annually. The NSF tests and certifies biosafety cabinetry to the standard NSF/ANSI 49, which verifies the BSC meets basic requirements for design, construction and performance. In addition to the NSF/ANSI 49 standard, some BSCs may also be certified to meet the requirements of other standards, such as the European EN 12469 standard.

Certification provides assurance that the cabinet has been independently tested and meets the required safety and performance criteria. It also gives users confidence that the cabinet is effective in protecting laboratory personnel, the environment, and the product from hazardous or potentially hazardous particulates.

The Purair® BIO biological safety cabinet (BSC) is certified for safety and performance in accordance with NSF/ANSI Standard 49 and EN12469 which certifies Class II, Type A2 laminar flow cabinets are suitable for working with biosafety agents at levels 1, 2 and 3.

3. Filter Integrity

The next important factor to consider when choosing a biological safety cabinet is filter integrity. HEPA filter quality is essential. Not all HEPA filters on the market are of the same quality. Inferior manufacturing practices and low-quality components can lead to filters that are dangerous to use. HEPA (High-Efficiency Particulate Air) filters are used to capture greater than 99.995% of airborne particles at 0.3 microns.

Regular filter integrity testing is crucial to ensure that the HEPA filters are functioning properly and maintaining the required level of protection. There are various methods for testing filter integrity, including the DOP (dioctyl phthalate) test and the aerosol photometer method. The DOP test involves releasing a DOP aerosol into the cabinet and measuring the concentration of particles downstream of the HEPA filter. The aerosol photometer method measures the light scattering of particles passing through the HEPA filter.

HEPA filter integrity testing requirements vary by region, so it is crucial to review your specific requirements.

4. Airflow

Biological safety cabinets provide a safe laboratory workspace using an integrated HEPA filtration system combined with an optimum airflow design. Airflow is therefore an integral component that ensures the continued safety of your workspace.

A well-designed airflow system draws in room air, passes it through a HEPA filter to capture contaminants, and then directs the purified air in a vertical laminar flow pattern toward the work surface. This continuous flow of HEPA-filtered air creates a negative pressure environment within the cabinet, preventing the escape of hazardous particulates and effectively containing potential biohazards.

The airflow velocity also plays a crucial role in the cabinet’s performance. Uneven airflow increases the likelihood of uneven particulate loading in the filter. Dual motor designs can introduce a number of problems, including unbalanced airflow and uneven filter loading. Airflow adjustments are simpler, operational costs lower and maintenance easier for BSCs equipped with single EC blower motors.

By carefully considering the airflow design, velocity, and maintenance requirements, laboratories can select biological safety cabinets that provide a safe and controlled environment for handling hazardous microorganisms, protecting both personnel and the surrounding environment from potential contamination.

5. Efficiency

Efficiency is a crucial factor to consider when choosing a biological safety cabinet. The most efficient BSCs are those designed with ergonomics and flexibility in mind in addition to energy efficiency. An efficient cabinet can save you time, money, and energy.

  • Ductless. Because conditioned air is not externally vented with a ductless BSC, these can help reduce HVAC loads and thereby reduce energy consumption for applications that do not require chemical fume protection.
  • Flexible. The Purair BIO includes multiple service connections for maximum flexibility. It includes duplex electrical outlets with splash-proof, UL listed covers. CSA certified service valves for gas, air and vacuum are also available. They can accommodate a maximum working pressure of 75 PSI.
  • Safe. The anti-ultraviolet, 6 mm tempered glass ensures maximum protection for the operator.
  • Ergonomic. The user interface combines ergonomics, safety and aesthetics with a 10° angled window design that reduces operator head and elbow discomfort, as well as eye strain and fatigue.
  • Slim-Profile. The Purair BIO is one of the narrowest BSCs on the market and permits easy passage through standard doorways.

The Purair BIO has been designed with efficiency, flexibility, and safety in mind. It features an ergonomic design and a low noise level, so it won’t disrupt your work. The Purair BIO can be used for various applications and has a wide range of accessories available, so you can customize it to meet your specific needs.

From assessing the required level of protection to evaluating certification, filter integrity, airflow, and overall efficiency, each element plays a crucial role in safeguarding your laboratory and personnel.

Shop online at to find the perfect BSC for your laboratory today.