Biosafety Cabinets are specialized workstations widely used in scienitific  and industrial laboratories where experiments need highly contaminant free environment.. Also known as biological safety cabinets and biohazard safety cabinets, these are made in three different class types such as Class 1, Class 2 and Class 3; in which Class 2 is widely used in microbiology laboratories It is biosafety level factor which decides which bsc should be used in laboratory.

The primary purpose of a BSC is to serve as a means to protect the laboratory worker and the surrounding environment from pathogens. All exhaust air is HEPA-filtered as it exits the biosafety cabinet, removing harmful bacteria and viruses. These Biosafety Cabinets have downward airflow and HEPA filters that re-circulate air providing required level of protection from microorganisms and aerosols.


The cabinets are fabricated out of thick high grade steel. The work table is made of Heavy gauge S.S. sheet and is fitted with U.V. Germicidal Light, static pressure Manometer, Exhaust System (suitable for 6 feet duck) and Virus Burn out Unit. Side panels are made out of thick transparent plexi glass duly framed. The unit is fitted with pre-filter and HEPA Filter. Air is drawn through pre-filter and  is made to pass through highly effective HEPA (High Efficiency Particular Air) filters having efficiency retaining all air-boarne particles of size 0.3 micron and larger. Using a dynamic balancing machine, the blower and motor assembly is statically and dynamically balanced. Motor of 1/4 H.P. capacity operates with minimum noise level. The working area is illuminated by fluorescent lighting fitted to the unit. The height of the working table provides a comfortable “SIT DOWN” working position for the operator. In addition to the above futures of a standard Vertical Laminar Flow Bench, the  Bio-safe cabinets have arrangements for re-circulating a part of the air thus creating highest level of clean air. The unit is also convertible to the conventional vertical laminar flow bench with downward air flow by lifting the sliding front door upwards. Air is sucked through the pre-filter and the excess air is thrown out from the top. through a HEPA filter of size 1′ x 1′ x 6’’. Supplied with glove ports, gauntlets, HEPA filter, Pre-filter, U.V. light and fluorescent light.


Biological safety cabinet classes (or biosafety cabinet classes) are classified into classes:

Class I :

Class I cabinet is defined as a ventilated cabinet for personnel and environmental protection. Class I cabinets do not offer product protection from contamination, significantly limiting their applications. they also have a HEPA filter at the exhaust outlet. They may or may not be ducted outside.

The air enters the cabinet via the front aperture passing through a built-in exhaust fan, HEPA filter thus providing operator and environmental protection. The escape of any airborne particulates generated within the cabinet are therefore controlled by means of the inward airflow through the front aperture and by filtration/absorption of the exhausted air.
Unlike fume hoods, the HEPA filter in the cabinet protects the environment by filtering the air before it is exhausted.

Class II :

Class II cabinet is defined as a ventilated cabinet for personnel, product and environmental protection for microbiological work or sterile pharmacy compounding. It has downward HEPA-filtered laminar airflow (product protection) and HEPA-filtered exhaust air (environmental protection).

The air in the work chamber has to pass through two sets of main HEPA filters. This makes the triple filter cabinet the ideal choice of cabinet for working with hazardous materials.The triple filter Biological Safety Cabinet is easier to service as no prior decontamination is needed.

They are further classified into different types :

Type A cabinets are suitable for microbiological research with the absence of any volatile or toxic chemicals .they  arefurther divided into types A1 and A2.

Type A1:

  • 70% air recirculated;
  • 30% exhausted through HEPA filter
  • 75FPM intake;
  • HEPA filtered air can be exhausted outside atmosphere.
  • may have biologically contaminated positive pressure plenum

 Type A2 :

  • 70% air recirculated;
  • 30% exhausted through HEPA filter
  • 100FPM intake;
  • biologically contaminated surrounded by negative pressure

Type B cabinets are hard-ducted to the building exhaust system and are further divided into types B1 and B2.

Type B1:

  • 40% air recirculated; 60% exhausted from cabinet;
  • exhaust air pulled through dedicated exhaust duct into facility exhaust system;
  • 100FPM intake
  • all ducts and plenums are under negative pressure

 Type B2:

  • 0% air recirculated; 100% exhausted from cabinet
  • exhaust air pulled through dedicated exhaust duct into facility exhaust system;
  • 100FPM intake
  • all ducts and plenums are under negative pressure

Type C1:

  • Cabinet must maintain a minimum average inflow velocity of 105 fpm through the sash opening.
  • They can operate as either a Type A cabinet when in recirculating mode or a Type B cabinet when exhausting.

Class III:

A Class III cabinet is defined as a totally enclosed, ventilated cabinet with leak-tight construction and attached rubber gloves for performing operations in the cabinet. The cabinet is maintained under negative pressure and supply air is drawn in through HEPA filters. The exhaust air is treated with either double HEPA filtration or HEPA filtration and incineration.

Working Size 2′ x 2′ x 2′ 3′ x 2′ x 2′ 4′ x 2′ x 2′ 5′ x 2′ x 2′ 6’x2’x2’
Size of HEPA Filter 2′ x 2′ x 6” 3′ x 2′ x 6” 4′ x 2′ x 6’’ 5′ x 2′ x 6’’ 3’x2’x6”
No. of HEPA Filter 1 1 1 2 2
Illumination 1 x 20 W 1 x 20 W 2 x 40 W 2 x 40W 2 x 40 W
Noise Level Less than 60 db
Filter HEPA filter 99.999% efficient (ULPA – Optional)
Particle retention 0.3 micron
Controller Microprocessor controller with digital display
Material of construction High grade stainless steel
Optional   Supplied with complete body pasted in rolled cold steel 304 grade in lieu of sun mica.

Fitted with electronic controller with air velocity measurement features a power on of the PCB,GLCD showing the controlling of the different parameters & 8 keys to control different parameters .

1.     Automatic U.V light age circulating facility

2.     Real time clock

3.     Air velocity measurement in m/s through special sensor

4.     Filter choke indication

5.     Timer for U.V light operation

6.     Timer for blower operation

7.     The menu driven system allow the user to set multiple parameters               easily.

8.     Password protected menu system

9.     Blower timer range 24 hours settable in menu.

10.   Alarm indication when timer gets finished.