Fume Hood Usage Guide

Fume Hood Usage Guide:

Variable Air Volume ("Phoenix" system)

By following a few simple guidelines, the effectiveness of your fume hood can be increased significantly and your exposure to harmful substances can be reduced. VAV hoods — unlike a conventional hood — automatically adjust the face velocity to stay within recommended safe work levels.

If the low flow alarm engages, lower the sash until the alarm stops.DO NOT over-ride the safety alarm by permanently engaging the "Mute" or "Emergency" button (e.g., with tape). If your hood is consistently alarming call EH&S at the above phone numbers.

Always work with the sash at or below the level of the arrow sticker and close the sash when not in use for the following reasons:

If most or all bldg. sashes are fully raised, this will generate an alarm at your hood, and your neighbor’s hood, due to the limited capacity of the bldg. fans.

A lowered sash protects you against airborne chemicals and incidents up to 100 times more than at sash full open.

To comply with OSHA safety requirements and ensure a face velocity of 100 to 120 ft/min.

The lower the sash, the greater the energy conservation.

When NOT USING your hood, lower the sash all the way to ensure that there is sufficient air flow in all the hoods in the building.

Store only the bare minimum of equipment and chemicals in your hood because:

Excess materials should not be stored in the hood and permanent equipment should be raised on a stand and kept at least 6 inches back from the front edge to allow the air flow into the lower slot.

Minimize chemicals stored in the fume hood to prevent potential fires and explosions.

Hoods are fitted with vented, labeled cabinets for storage of flammable liquids to reduce the fire hazard, lab smells and cabinet corrosion.

Improper use of perchloric acid has resulted in fires or explosions within fume hood systems. If you want to use perchloric acid you must first contact EH&S (x-3743, x-8787 or x-4899) for technical assistance on proper procedures and equipment.