VFHOMT-11/18 -
3
Operating Procedures
Procedures for Perchloric Acid Fume Hoods
When heated, Perchloric Acid becomes a strong oxidizer producing unstable
residues which contaminate the fume hood and ductwork and produce an
explosion hazard. The following additional precautions should be followed when
heating perchloric acid.
1. Use this hood only for Perchloric Acid procedures. Perchloric Acid may react
with organic materials to create an explosion hazard.
2. Operate the water wash down system for 15 minutes after each use. If the
hood is used continuously during the work day, then the wash down system
should be used at the end of the work day.
During the wash down procedure a small amount of water may drip into
the hood work area. Prior to operating the wash down system clear the
hood work area of any materials or equipment that may be damaged or
contaminated by this water.
The exhaust fan should be turned off during the operation of the wash
down system. The fan impeller wheel may be damaged by the water spray
impacting on it at a high velocity.
The valve for the hood wash down is located on the left front vertical fascia.
There may be a separate valve or switch for activating the wash down system
for the duct.
3. Approximately once a week, clean the interior surfaces of the work area with
water.
4. Place large hot plates on 2” or 3” tall metal legs to allow air flow below the hot
plate.
5. The use of other inorganic acids in the hood may adversely affect the
stainless steel liner and necessitate more frequent cleaning and operation of
the wash down system.
Summary of Contents for Supreme Air Series
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