Do not use any metallic pads. Instead, for stubborn stains, use a plastic
light-duty cleansing pad and rub GENTLY in the direction of the metal
grain.
Caution
Extreme care must be taken when handling the materials
described below. Always work in an area with adequate ventilation. Use the
precautions as outlined in the Material Safety Data Sheet (MSDS) and the
manufacturer instructions for the product being utilized. Also, follow the
personal protection index found in the Hazardous Materials Information
System (HMIS) section of the MSDS.
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If stains continue to persist, use one of the following chemicals and
methods:
• Any of a variety of “scale removers” available at local supermarkets or
hardware stores used for the cleaning of coffee marks, humidifiers or
vaporizers.
• A 15% to 35% phosphoric acid solution available from laboratory
supply distributors for scale and rust removal. Allow solution to soak
the surface affected until rust and scale is loosened. Immediately follow
with a clean water rise.
• Citric acid based cleaners.
• Bathroom tub and tile cleaners.
• A mixture of 20% nitric acid and 1.5% hydrofluoric acid (or 1.5%
hyrochloric acid). Swab solution on surface allowing it to remain until
rust is loosened. Immediately follow with a clean water rise. (This
method should ONLY be used if SEVERE rust and scale stains are
present.)
• Oxalic acid 2% to 5% in warm water. Swab solution on surface
allowing it to remain until rust is loosened. Immediately follow with a
clean water rise. (This method should ONLY be used if SEVERE rust
and scale stains are present.)
Regardless of the approach utilized, ALWAYS follow the manufacturer
ʼ
s
directions and allow the chemicals to do the cleaning with MINIMAL
scrubbing.
Always follow cleanings with a clean water rinse. Air dry.
Note
The use and disposal of these chemicals may be regulated by your
local city codes; consult those regulations before of disposing of these
materials.
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7-4
Vacuum Oven
VWR Collection
Section 7
Maintenance
Cleaning Methods
