The Importance of Industrial Fans in 3 Common Fume Extraction Systems
A properly designed fume extraction system will collect the air that contains contaminants, make sure they are contained and taken way, and if necessary, clean the air and discharge safely into atmosphere. In this section we’ll look at the main extraction systems that you’ll come across. These can occur in many industries including laboratory, water treatment and environmental sectors.
The size of the fan required in fume cupboards depends on factors related to the specific application and the design of the fume cupboard system. As their primary function is contain within the fume cupboard, or hood, then to effectively extract and remove chemical fumes and contaminants, the fan size is determined by the required airflow rate. The containment requirement determines the need to extract and remove. This should be specified by the fume cupboard manufacturer or governed by safety guidelines.
Important Formula: Sash Size x Capture Velocity = Airflow Volume
Manifold extraction systems are designed to extract fumes from multiple sources and channel them through a centralised ductwork system. These systems are commonly used in industrial and lab settings where there are multiple workstations or processes generating chemical fumes or hazardous substances. The layout and design of the ductwork system play a significant role in determining the fan size used in manifold systems. The length, diameter, and complexity of the ductwork, as well as the number of bends, elbows, and transitions can create resistance to airflow. The fan must have enough capacity to overcome the resistance and maintain the required airflow rate throughout the system.
The total airflow required to extract fumes from all sources needs to be calculated. System configurations such as whether a single central fan system, or multiple fans serving different sections, can affect the size and the capacity of the required fan. We recommend you work with suppliers who have experience in fume extraction systems to accurately select the appropriate fan for the manifold system.
Fan volume is determined by the volume that comes through the ductwork served and connected to the fan.
When selecting corrosion resistant fans for local exhaust ventilation systems that require chemical resistance, it is important to consider the specific corrosive agents present in the environment. Corrosion resistant fan selection ensures the longevity and performance of the fan in the presence of corrosive substances. Therefore, you should identify the specific gases that the LEV system will be exposed to. These include acidic fume, alkalis
corrosive gases and other chemicals. Understanding the nature and concentration of these agents is crucial for selecting a fan with the appropriate corrosion resistance. Choose fans constructed from materials that offer high resistance to corrosion. Polypropylene Is the preferred choice as it aligns with the protection required for most corrosive substances.
Visit www.axair-fans.co.uk to download a wide range of resources and to view more technical information. We update our website regularly with industry leading technical content, case studies, product information and key industry legislation. If you have any additional requirements or questions about specifying our corrosion resistant polypropylene fans in your laboratory or construction specification, contact us on [email protected] or call 01782 349 430.
Fume Cupboards & Fume Hoods
The size of the fan required in fume cupboards depends on factors related to the specific application and the design of the fume cupboard system. As their primary function is contain within the fume cupboard, or hood, then to effectively extract and remove chemical fumes and contaminants, the fan size is determined by the required airflow rate. The containment requirement determines the need to extract and remove. This should be specified by the fume cupboard manufacturer or governed by safety guidelines.
Important Formula: Sash Size x Capture Velocity = Airflow Volume
Key Considerations in Fume Cupboards & Hoods
Face Velocity
Face velocity refers to the speed at which air is drawn into the fume cupboard opening or sash. It is an important parameter to consider when selecting a fan. The fan size must be capable of providing the necessary airflow to maintain the desired face velocity, ensuring that the fumes are accurately contained within the fume cupboard. Learn more about velocity pressure here.Static Pressure
The fan must generate enough static pressure to overcome the resistance offered by the fume cupboard and the associated ductwork.Ductwork Design
Fans must have sufficient capacity to overcome the resistance from the length, diameter, air velocity, and configuration of the ductwork, while maintaining the airflow rate throughout the system.Noise
Fume cupboards are often located within laboratory or workspace environments where noise levels must be kept at an acceptable level. Consideration should be given to selecting fans with low noise levels especially if they will be in close proximity to workstations or occupied areas. This is particularly important for ductwork. High velocity will cause high noises.Manifold Fume Extraction Systems
Fans for manifold systems must have enough capacity to overcome any resistance and maintain the required airflow rate throughout the multi source system.
Manifold extraction systems are designed to extract fumes from multiple sources and channel them through a centralised ductwork system. These systems are commonly used in industrial and lab settings where there are multiple workstations or processes generating chemical fumes or hazardous substances. The layout and design of the ductwork system play a significant role in determining the fan size used in manifold systems. The length, diameter, and complexity of the ductwork, as well as the number of bends, elbows, and transitions can create resistance to airflow. The fan must have enough capacity to overcome the resistance and maintain the required airflow rate throughout the system.
The total airflow required to extract fumes from all sources needs to be calculated. System configurations such as whether a single central fan system, or multiple fans serving different sections, can affect the size and the capacity of the required fan. We recommend you work with suppliers who have experience in fume extraction systems to accurately select the appropriate fan for the manifold system.
Fan volume is determined by the volume that comes through the ductwork served and connected to the fan.
Local Exhaust Ventilation (LEV)
When selecting corrosion resistant fans for local exhaust ventilation systems that require chemical resistance, it is important to consider the specific corrosive agents present in the environment. Corrosion resistant fan selection ensures the longevity and performance of the fan in the presence of corrosive substances. Therefore, you should identify the specific gases that the LEV system will be exposed to. These include acidic fume, alkalis
corrosive gases and other chemicals. Understanding the nature and concentration of these agents is crucial for selecting a fan with the appropriate corrosion resistance. Choose fans constructed from materials that offer high resistance to corrosion. Polypropylene Is the preferred choice as it aligns with the protection required for most corrosive substances.
Visit www.axair-fans.co.uk to download a wide range of resources and to view more technical information. We update our website regularly with industry leading technical content, case studies, product information and key industry legislation. If you have any additional requirements or questions about specifying our corrosion resistant polypropylene fans in your laboratory or construction specification, contact us on [email protected] or call 01782 349 430.