Tips for Effective Fume Hood Use 

Do….

• Perform all work that involves hazardous and noxious materials in the hood.
  
• Keep the sash height at or below the arrow on the hood inspection label. This indicates minimum working height to maintain the hoods face velocity at ~100 FPM.
  
• Elevate large apparatus at least 2 inches from the hood deck to allow air to flow around the object and eliminate “dead-air” zones. (Except where rotating equipment is used that may become unstable if elevated.)
  
• Work at least 6 inches into the face of the hood to reduce the effect of turbulence. Use a piece of tape to mark the deck of the hood.
  
• Work extending arms under or around the sash, placing the head behind the sash, with the glass between the worker and the chemical source. The sash will act as a primary barrier in the event of spill, splash or explosion.
  
• Assure that the controls for all services (i.e., vacuum, gas, electric) are located outside of the face of the hood.
  
• Put the minimum amount of materials in the hood required for the current operation. Each additional item in the hood creates additional turbulence and potential for gas/vapor escape.
  
• Have a safety plan that includes emergency operations for each procedure that you begin in the hood. What will you do if the hood breaks down or an accident occurs?
  
• Collect large amounts of chemical vaporized in an operation by distillation or other means. Dispose of collected material as a waste. Minimize waste by adding a step to render the waste non-hazardous.

Don’t….

• Walk directly behind someone working in a hood. (Your draft can pull fumes out of the hood.)
  
• Raise or lower the sash quickly. (Same drafts.) · Cover air vents, move ceiling tiles, use small fans, open windows or otherwise alter the air distribution patterns in the lab. Air distribution in the room affects hood function.
  
• Store chemicals, waste or equipment in the hood. They block the baffles and create “dead-air” zones.
  
• Use perchloric acid in a standard hood. Use a water-washed hood.
  
• Use infectious materials in a chemical fume hood. Hood Maintenance….
  
• Hood inspection stickers should be current within one year.
  
• Face velocity should measure between 80 –120 fpm.
  
• If you use flammable liquids be sure you have an explosion proof fan motor attached to your hood. (Vapors from some distillations can exceed 20 % of the lower explosive limit of some solvents.)
  
• Report suspected hood malfunctions to Environmental Health and Safety to have the hood tested and ECU Facilities Services for specific repairs.