What is laboratory fume hood?
Laboratory fume hood

Laboratory fume hood which is also called
chemical fume hood is an essential part of laboratory design, it is also a kind of local exhaust equipment commonly used in the laboratory. Due to the variety of lab fume hoods, their structure is different, the use of different conditions and the exhaust effect are not the same. Fume hood performance is good or not, mainly depending on the speed of air movement through the fume hood.
In the chemical laboratory, the experimental operation produces a variety of harmful gases, odor, moisture, and flammable, explosive, corrosive substances, to protect the safety of users, to prevent the diffusion of pollutants in the experiment to the laboratory, in the vicinity of the pollution source to use laboratory fume hood.
Biosafety cabinet

Biosafety cabinet is a box-type negative pressure safety device for air purification which can prevent aerosol escape from some dangerous or unknown biological particles in the process of experimental operation and treatment.
It is widely used in scientific research, teaching, clinical testing, and production in microbiology, genetic engineering, biological products, and other fields. It is the most basic safety protection equipment in experiment.
Laboratory fume hood function
There is mainly six functions about laboratory fume hood:
1. Release function
Chemical fume hood can absorb harmful gas generated inside the fume hood and let it dilute and exclude outdoor.
2. Non-reverse flow function
Lab fume hood has the function of reversely flowing harmful gas into the room from the inside of the fume hood by the airflow generated by the exhaust fan.
3. Isolation function
Fume hood in a lab has equipped with a non-sliding glass window to separate the inside and outside of the fume hood.
4. Supplement function
When discharging harmful gases, laboratory fume hood can inhale air from outside.
5. Air velocity function
To prevent the harmful gases in the fume hood from escaping, it is necessary to have a certain absorption speed. The factors that determine the suction speed of the ventilation cabinet are: the heat generated by the experimental content and the relationship with the number of air changes, experiment content, and harmful substances are the main factors. The general rules are as follows:
Attribute | Air velocity |
Generally non-toxic contaminants | 0.25―0.38m/s |
Noxious or dangerous substance | 0.4―0.5 m/s |
Highly toxic or slightly radioactive | 0.5―0.6m/s |
Gas substance | 0.5m/s |
Particulate material | 1m/s |
To ensure such wind speed, the exhaust fan should have the necessary static pressure, that is, the friction resistance of air passing through the fume hood. In addition, noise problems should be also pay attention to determining air velocity. When the air flows in the pipe, it is limited to 7-10m, and noise will be generated if it exceeds 10m. Usually, the noise limit of the laboratory is 70dBA. Increasing the pipe cutting area will reduce the wind speed and noise.
6. Acid and alkali corrosion resistance
Some of the electric furnaces should be placed in chemical fume hoods. Because some experiments produce a large number of acid and alkali and other toxic and harmful gases with strong corrosion, the mesa of the fume hood, the lining plate, the side plate, and the selected water nozzle and air nozzle has an anticorrosive function.
In corrosive experiments using sulfuric acid, nitric acid, hydrofluoric acid, and other strong acid occasions, the overall material of the fume hood is acid and alkali proof, and made of stainless steel or PVC material.
Laboratory fume hood components
Here are components overview of lab fume hood
1. Cabinet
Usually made of thick porcelain white PP, the door is made of porcelain white PP, which can be customized according to the different needs of customers, different sizes, the thickness of cabinet, acid and alkaline ability.
After CNC precision cutting integrated engraving processing, the same color homogeneous electrode fusion welding modification treatment, the surface without acute Angle.
* Upper part of cabinet: adopting top exhaust design, and there is an exhaust tuyere of ∮250mm. The guide plate is made of homogeneous PP material with strong acid and alkali resistance. The installation size is reasonable, and there is no dead angle of airflow, which can capture greater exhaust gas.
* Lower part of cabinet: it's a storage cabinet with a partition in the middle. Equip plastic hinge, corrosion resistance is good.
2. Operation table
Worktop is usually made of PP board, it can resist acid and alkali well, sink on laboratory fume hood counter can be configured according to user's requirements.
3. Adjusting door
* Glass of adjusting door: made of transparent tempered glass or organic glass, with excellent acid and alkali resistance.
* Border id adjusting door: Thick porcelain white PP board type C groove, it is built in combination to ensure safety and durability.
* Suspension cable of adjusting door: each laboratory fume adjusting door uses a cable to connect.
* Balance weight of adjusting door: A non-stage counterweight box design with a silent track to limit up and down travel to avoid rocking and collisions.
4. Electrical equipment
Consists of a switch, a light fitting and a socket section and son on.
Types of laboratory fume hood
Benchtop fume hood

Lining board | 5mm thick high quality pure material PP |
Cabinet | 8mm thick high quality pure polypropylene |
Guide plate | 5mm thick high quality pure polypropylene |
Circuit | LCD control panel, LED lights, 10A multi-functional splash socket |
Lighting | 220V, 12W fluorescent lamp is attached inside |
Window | tempered glass or PMMA |
Color | white |
Application: Research institutes, testing institutions, hospitals, universities
Features: Resistant to strong acid and alkali
Floor-mounted fume hood

Shell | 1.0mm cold-rolled steel plate with anti-rust treatment and electrostatic spraying |
Operation area | anti-double special plate |
Window | a manual window and can be stopped at any height within the travel range. |
Window glass | 5mm thick tempered glass |
Control panel | fluorescent lamp, and uses the wind speed adjustment knob to adjust the fan gear, realizing stepless speed regulation. |
Application: Research institutes, testing institutions, hospitals, universities
Features: With good corrosion resistance, anti-shock and other functions, stable performance, long service life, with power off memory function
Portable/Mini fume hood

Shell | cold rolled steel sheet, surface electrostatic spraying |
Glass of the door | tempered glass |
Lighting | a 8W LED light |
Display | LED display |
Additional function | ultraviolet lamp sterilization |
Application: Bio-pharmaceutical, pharmaceutical health, microbial detection
Features: small size,easy to carry, Intelligent multistage wind speed, protective test sample.
Stainless steel fume hood

Stainless steel | 1mm cold rolled steel sheet |
Glass of the door | tempered glass |
Application: scientific research institutions, chemical enterprises, medical places, chemical enterprises
Features: acid and alkali resistance, wear resistance, high temperature resistance, strong bearing capacity
Ductless fume hood

Metal parts | galvanized steel plate ≥1.2mm, electrostatic spraying with epoxy resin |
Door | ≥6mm acrylic plate |
Layer board | integrated PP tray |
Display | 7 inch LCD touch screen |
Lighting | LED light |
Application: Suitable for a variety of scientific laboratory fields
Features: Specially designed for toxic and harmful chemicals storage, ductless, easy installation, acid and alkali resistance, corrosion resistance, stable performance, super quiet.
Difference between a lab fume hood and biosafety cabinet

According to our previous definition of laboratory fume hood and biosafety cabinet, we can know that a lab fume hood is a ventilated cabinet that can remove harmful chemical fumes and volatile vapors from the laboratory and provide staff protection only. Biosafety cabinet and utilize HEPA filters to provide environmental, human, and product protection.
Although they are sometimes referred to collectively as "fume hoods," biosafety cabinets and laboratory fume hoods are two entirely different categories of laboratory equipment. Both are built to safely deal with scientific hazards, but they are different in the type of protection they offer, airflow, and application.
| Lab fume hood | Biosafety cabinet |
Protection | Provide personnel protection | Provide environmental, human and product protection |
Air flow | * Since fume hoods handle hazardous chemicals, air starts at the surface of the equipment, passes through the work surface and is sucked away through the duct system, where it is released into the atmosphere.
* Proper and undisturbed air flow in fume hood is essential. Do not store large equipment in fume hoods or do anything that may disrupt the flow of air inside the equipment. To maintain a safe and efficient working environment, do not place your head in the fume hood and keep window frames closed as much as possible. | All three biosafety cabinets share one common feature: HEPA filtration.
* In a class I biosafety cabinet, air is sucked away and across the work surface by laboratory staff.
* In a Class II biosafety cabinet, intake air is safely pumped around the operator, sterile air flows down to the work surface, and discharged air is filtered by HEPA and then recirculated to the laboratory or released to the atmosphere through a duct system or canopy connection.
* Class III biosafety cabinet is an airtight cabinet with both intake and exhaust filtered by HEPA.
HEPA: High Efficiency Particle Air |
Application | Can handle odorous substances, toxic gases, reactive substances, chemicals that may fly, aerosols, carcinogens, in-flammables or other toxic and volatile substances. | Biosafety cabinets provide a safe environment for research involving infectious microorganisms or other harmful particulates. |
Laboratory fume hood work practices
The safety of laboratory fume hood is related to the health and life safety of the laboratory staff. Therefore, how correctly operating the chemical fume hood is a necessary skill for laboratory staff. The following work practices about the lab fume hood.
1. Before use to check the lighting, the ventilation system is normal, will be used on both sides of the cabinet.
2. Pull the glass window down to your elbow during experiment to allow air to pass underneath.
3. The indoor air temperature is between -5℃ and 40℃, and the 24-hour average does not exceed 25℃.
4. Laboratory should often be ventilated even though lab fume hood is not used, it is beneficial to the health of the test personnel.
5. When more than two chemical fume hoods share one fan, the "on" and "off" of the fan can only be controlled by one operator to avoid improper operation. If another ventilation cabinet is temporarily not used or stopped using, the air volume control valve can be used to close the vent, to avoid repeating "on" and "off" the fan.
6. Avoid the interference of counter-current wind direction caused by personnel movement to the fume hood.
7. Open Windows for 10 minutes every 2 hours for ventilation. Use time more than 5 hours, to open the window, to avoid negative pressure indoor.
8. After the experiment, the exhaust fan should continue to run for several minutes, so that the exhaust gas in the cabinet is completely removed.
9. If appears malfunction, close the cabinet door immediately and contact the maintenance personnel.
10. The work surface must be cleaned after each use.
Laboratory fume hood safety

In the use of laboratory fume hood, in order to ensure safety, there are several points are forbidden to do:
1. Don’t do laboratory course even if the laboratory fume hood is not open.
2. Don’t put your head into the chemical fume hood for operation or inspection.
3. Don’t store or test inflammable and explosive materials in the fume hood.
4. Don’t place the moving plug bar or electric wire in the fume hood.
How to buy laboratory fume hood?
ANTITECK provide lab equipment, lab consumable, manufacturing equipment in life sciences sector. If you are interested in our
laboratory fume hood or have any question, please write an e-mail to
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