What is the meaning of biosafety cabinet?
Biosafety cabinet
Biosafety cabinet is the abbreviation of biological safety cabinet. It is a safety device with box-type negative pressure for air purification to prevent unknown biological particles in the process of experimental operation or aerosol dispersion of some dangers. Biosafety cabinet is widely used in biomedical, microbiology, biomedical products and other fields of scientific research and clinical testing, and is the most basic safety protection equipment in laboratory.
About Laminar flow hood
Laminar flow hood, also known as the clean bench, is designed to meet the needs of local work area cleanliness. The air is sucked into the pre-filter through the fan, and filtered into the HEPA filter through the hydrostatic chamber. The filtered air is sent out in the state of vertical or horizontal airflow so that the operating area can reach the cleanliness of 100 grade and ensure the production of environmental cleanliness requirements. Therefore, laminar flow cabinet does not belong to biosafety cabinet.
What is the principle of biosafety cabinet?
The working principle of biosafety cabinet is mainly to pump the air in the cabinet outward, so that the cabinet maintains negative pressure, through vertical airflow to protect the staff; the outside air in the cabinet also needs to be filtered by HEPA before being discharged into the atmosphere.
HEPA filter: The full name of HEPA filter is high efficiency particulate air filter, that is mainly used to capture particulate dust above 0.5um and various suspended solids as the end of various filtration systems. It is made of ultrafine glass fiber paper as filter material, sandwich paper, aluminum foil plate and other materials as well as galvanized sheet, stainless steel plate, aluminum alloy profile for the outer frame.
Biosafety cabinet parts and functions
There are main five parts and functions of biosafety cabinet:
1. Air filtration system
Air filtration system is the most important system to ensure the performance of biosafety cabinet, which is composed of driving fan, air duct, circulating air filter and exhaust air filter. Its main function is to continuously make clean air into the studio, so that the flow rate of the downdraft (vertical airflow) in the work area is not less than 0.3m/s, to ensure that the cleanliness of the work area reaches 100. In the meantime, the discharged air is also purified to keep off environmental pollution.
The core component of the system is HEPA filter, which uses special fireproof material as the frame. The frame is separated by corrugated aluminum sheets into grids and filled with emulsified glass fiber sub-particles. The filtration efficiency can reach 99.99%~100%. The pre-filter cover or pre-filter of the air inlet makes the air pre-filtered and purified before entering the HEPA filter, which can prolong the service life of the HEPA filter.
2. Exhaust bellows system
The exhaust bellows system consists of the exhaust bellows shell, fan and exhaust pipe. The exhaust fan provides the power of exhaust, the unclean air in the working room is extracted and purified by the exhaust filter to protect the sample and the experimental items in the cabinet. Because of the effect of exhaust, the working area is negative pressure to prevent the air escape in the working area, and to protect the operator.
3. Slide front window drive system
Sliding front window drive system consists of front glass door, door motor, traction mechanism, drive shaft and limit switch, etc. The main function of biological safety cabinet is to drive or traction each door shaft, so that the equipment in the operation process, the front glass door in the normal position.
4. Lighting system
The light source and ultraviolet light source are located inside the glass door to ensure certain brightness of the working room and disinfection of the table and air in the working room.
5. Operation system
The control panel has power supply, ultraviolet lamp, floodlight, fan switch, control front glass door movement and other devices, the main function is to set and display the system state.
Types of biological safety cabinet
According to the NSF49 standard, we can divide biological safety cabinet into three classes to satisfy different demands between biological research and immunization requirements.
Biosafety cabinet class 1
Biosafety cabinet class 1 can protect laboratory staff and environment but not protect samples. The airflow principle is the same as that of the laboratory fume hood, except that the exhaust port is fitted with a HEPA filter. All types of biological cabinets use HEPA filters at the exhaust and intake ports. Cabinet class 1 has no fan and relies on the fan in the external connected air pipe to drive the airflow. Since it cannot provide protection for test products or products, it is seldom used at present.
Biosafety cabinet class 2
Biosafety cabinet class 2 also has air flow into the front window opening, known as "inlet air flow", to prevent the escape of aerosols that may be generated during microbial operation from the front window.
Unlike cabinet class 1, the unfiltered air intake flow is captured by the air intake grille before reaching the work area, so the test product is not contaminated by outside air. A feature of biosafety cabinet level 2 is that vertical laminar airflow filtered through the HEPA filter blows down from the top of the cabinet, known as "downdraft". The downdraft constantly blows through the working area of the safety cabinet to protect the test products in the cabinet from external dust or bacteria contamination. All cabinet class ii can provide protection for operators, environment and products. It is a widely used cabinet type at present.
According to the provisions of NSF49, biosafety cabinet class 2 can be divided into 4 types according to the inlet airflow speed, exhaust mode and circulation mode: A1, A2, B1 and B2.
Types of class 2 | Inlet airflow speed | Exhaust mode | Circulation mode |
A1 | Minimum airflow velocity or average measurement shall be at least 0.38m/s | 30% of the gas is filtered out through the exhaust port | 70% of the gas is recirculated through the HEPA filter to the work area |
A2 | Minimum flow velocity or average measurement shall be at least 0.5m/s | 30% of the gas is filtered out through the exhaust port | 70% of the gas is recirculated through the HEPA filter to the work area |
B1 | Minimum flow velocity or average measurement shall be at least 0.5m/s | 70% gas is removed through the HEPA filter at the exhaust port | 30% of the gas is recirculated to the work area through the supply port HEPA filter |
B2 | Minimum flow velocity or average measurement shall be at least 0.5m/s | 100% of the platoon type | No internal circulating air flow |
Among them, biosafety cabinets class 2 type B are all safety cabinets connected with the exhaust system. The fan connecting the exhaust pipe of the safety cabinet is connected to the emergency power supply, so as to maintain the negative pressure of the safety cabinet in case of power failure, so as to avoid dangerous gas leakage such as laboratory.
Biosafety cabinet class 3
Biosafety cabinet class 3 is designed for level 4 laboratory biosafety level, which is the world's current safety protection level safety cabinet. The cabinet is completely airtight, 100% full discharge type, and all gases do not participate in the circulation. The staff operates through the gloves connected in the cabinet, commonly known as glove box. The test products come in and out of the safety cabinet through the double-door transfer box to avoid contamination, which is suitable for high-risk biological tests.
Biosafety cabinet features
Nowadays, biological safety cabinet class 2 a1 and b2 are widely welcome, here are some features about these two types of bio cabinet in our company.
Biosafety cabinet class 2 type a2
Name | All steel biosafety cabinet |
Type | Class II A2 |
Material | High-quality stainless steel in the working area |
Work area dimensions | 1000*700*600mm |
External dimension of device | 1200*800*2120mm |
Weight | 130kg |
Average wind speed | 0.25m/ s-0.5m/ s |
The power supply | 250V50Hz |
HEPA dimensions | 980*520*50 |
Floodlight | 21W*2 |
Germicidal lamp | 14W*1 |
Features:
1. Air curtain isolation design to prevent internal and external cross-contamination. (negative pressure)
2. Move glass door up and down, with height limit alarm prompt.
3. A special filter is set at the exhaust to control the discharge of pollution.
4. Equipped with a special waterproof socket.
5. LED panel control.
6. The working area is equipped with a 2KW standby socket.
Biosafety cabinet class 2 type b2
Name | B2 biosafety cabinet (100% Exhaust outward ) |
Type | Class II B2 |
Material | High-quality stainless steel in working area |
Work area dimensions | 1000*650*580mm |
External dimension of device | 1300*800*1950mm |
Weight | ≤250kg |
Average wind speed | 0.26m/ s-0.5m/ s |
The power supply | 250V50Hz |
HEPA dimensions | 1050*600*50 |
Floodlight | 20W*1 |
Germicidal lamp | 20W*1 |
Features:
1. Quasi - closed glass door, effectively prevent external air penetration.
2. Adopt an adjustable air volume fan system to ensure the working wind speed is in an ideal state.
3. LED panel control.
4. The laboratory adopts stainless steel, easy to operate.
What is the difference between biosafety cabinet and laminar flow cabinet?
| Biosafety cabinet | Laminar flow cabinet |
Function | Negative pressure safety device for air purification. | Make the operation area reach 100-grade cleanliness, and ensure the production of environmental cleanliness requirements. |
Type | Class 1
Class 2
Class 3 | horizontal laminar flow
vertical laminar flow |
Application | * Microbiology
* Biomedicine
* Genetic engineering
* Biological products and other fields | * Medicine and health
* Bio-pharmaceutical,
* Medical science experiment
* Electronics
Plant tissue culture inoculation,etc |
Advantage | Higher cleanliness level | High work efficiency, short preparation time |
How to use biosafety cabinet?
1. When using the biosafety cabinet, you must wear personal protective clothing and gloves, which should be on the outside of the isolation clothing. Gloves, masks, hats, and shoes should be used correctly, and protective eye masks or masks should be worn if necessary.
2. The use of open flames can affect airflow and pose a hazard when handling volatile and flammable materials. Therefore, avoid using open flame sterilizers such as alcohol lamps. When sterilizing the inoculating ring, an infrared electric heater can be used, or a disposable plastic inoculating ring can be used.
3. When working, try to reduce the movement of the arm, and move slowly to prevent interference with the airflow in the cabinet.
4. The laboratory operation o
n the counter surface shall be conducted in the direction from the clean zone to the contaminated zone, with all operations performed in the middle and rear of the counter surface.
5. Keep biological safety cabinet in a continuous working state as far as possible, and sterilize the surface of all items to provide a certain degree of personnel protection; Take potentially contaminated items from inside the safety cabinet, and be sure to disinfect the surface.
Biosafety cabinet maintenance
1. Clean and disinfect the inside and surface of the biosafety cabinet every day.
2. Clean and disinfect the collecting tank every week.
3. Wipe the external surface of biological safety cabinet every month.
4. Clean stainless steel surface quarterly.
5. Maintain and inspect the biosafety cabinet every year.
How to order biosafety cabinet?
ANTITECK provide lab equipment, lab consumable, manufacturing equipment in life sciences sector. If you are interested in our
biosafety cabinet or have any question, please write an e-mail to
[email protected], we will reply to you as soon as possible.