How To Properly Size A Blower For A Fume Hood

A fume hood works only as well as the blower used with it. First, a Blower must be properly selected for each installation: chemical resistance, airflow, and static pressure.

There are 2 different types of configurations, a built-in Blower and a Remote Blower configuration. A Built-in Blower's installation is simple and economical. It's ideal for short, straight duct runs and low toxicity applications, but gnereally noisier than remote installations. A Remote Blower is the most common type of installation. It's quieter than the built-in blowers and can be sized for length of duct run.

Labconco outlines the steps needed to properly size a remote blower for a fume hood: 

• Finding Fume hood data/ design requirements
• Detail the Duct Run
• Defining the “System”
• Determine equivalent duct run length
• Find SP loss through duct
• Determine Total SP loss
• Correction Factors
• Select blower