The Class 2 Biological Safety cabinet must meet personnel, environmental and product protection requirements. The air flow is drawn into the working room through the front opening and continues under the bench and exits to the back plenum, where 70% is recirculated through the main HEPA filter and 30% comes out of the HEPA filter exhaust. Vertical laminar flow Biological Safety Cabinet provides operator protection

through inflow, product protection through downstream, and environmental protection through filtered exhaust.

The Biological Safety Cabinet is equipped with double HEPA filters according to European standard EN 12469. It can also be produced with triple filters according to DIN 12980. The triple HEPA filter system ensures that cross-contamination is eliminated as the air in the working room must pass through two main sets of HEPA filters. This makes the triple filter cabinet the ideal cabinet choice for working with hazardous materials such as cytostatics, virus manipulation and category 3 pathogens. The triple filter Biological Safety Cabinet is easier to service since no decontamination was required before.

Class 2 Biological Safety Cabinet has three main features:

Carefully a front opening with constant inward air flow.

Vertical, unidirectional air flow with HEPA filter in the work area.

Exhaust air with HEPA filter in the room or exhaust connected to an external extraction system.

As Class II designs allow different airflow patterns, velocities, HEPA air filter position, ventilation rates, and exhaust methods, some sort of classification is required to distinguish Class II safety cabinet variants.

Class 2 Biological Safety Cabinets Types

There are two different types (Type A and Type B) depending on their structure and configuration.

These are classified according to the percentage of air circulating from the common air plenum. In addition, cabinets have different exhaust vehicles, some of which can be returned directly to the laboratory, while others can supply air to an external ventilation system through the duct.

Type A cabinets are suitable for microbiological research without any volatile or toxic chemicals since air is circulated inside the cabinet. This cabin type is also subtype to A1 and A2 types.

A1 Biological Safety Cabinet

Downstream with HEPA filter.

70% of the air is recirculated in the cabin.

30% of HEPA filtered air is delivered to the laboratory or outside atmosphere.

HEPA filtered air can be sent back to the laboratory or outside atmosphere via the ferrule-type duct connection.

Alternatively it has a biologically contaminated positive pressure plenum.

A2 Biological Safety Cabinet

Downstream with HEPA filter.

70% of the air is recirculated in the cabin.

30% of the HEPA filtered air is discharged into the laboratory or outside atmosphere either through a ferrule duct connection.