A chemical fume hood serves as a critical safety control, shielding individuals from volatile and hazardous chemicals. Its design includes a continuous airflow that enters the hood, effectively capturing hazardous substances. This contaminated air then travels through ductwork and is ultimately exhausted through the building’s roof stack. However, it’s essential to recognize that the hood’s effectiveness hinges on proper work practices at the hood’s front face and the overall laboratory conditions. The following are some general guidelines to keep in mind when using a fume hood:
- Training is required prior to using fume hoods. If you do not have the proper training, please contact the district health and safety program coordinator.
- Fume hood exhaust systems should provide an average face velocity of at least 100 linear feet per minute (lfm) with a minimum of 70lfm at any point.
- Position chemicals six inches from the front of the sash to prevent accidental chemical exposure.
- Move slowly at or near the hood opening. Rapid movement creates disruption to the air flow and can cause exposure.
- Large items should be elevated 1 inch off the base of the hood, this allows air to flow underneath the items, sweeping the work surface.