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Acid Safety, continued
• If a cart is used to transport hazardous chemicals,
including acids, place compatible chemicals inside
an unbreakable secondary containment vessel,
such as a plastic tote. The cart should be equipped
with guardrails to prevent plastic totes or bottles
from sliding off the cart.
• If hazardous chemicals are moved from one floor
to another, use an elevator if possible. Only the
teacher transporting the chemicals should be on
the elevator. Although elevator accidents are rare,
should a dangerous material be released in an
elevator while passengers are trapped inside, the
results could be catastrophic.
Preparation of Acid Solutions
See page 717.
To Prepare a Solution
1. Add the appropriate amount of acid to about 2⁄3 of
the required amount of distilled or deionized water.
2. Always add acid to water! Never add water to
concentrated acids. The acid may splatter and
generate acidic steam.
3. Always use borosilicate (e.g., Pyrex®) glassware.
4. Stir to mix the solution.
5. Once the solution has cooled to ambient
temperature, dilute the solution to the proper
volume with water.
6. Use a volumetric flask for accuracy, if needed.
7. When diluting sulfuric acid, place the borosilicate
beaker or flask in an ice bath. The heat of dilution
of sulfuric acid is very high and may melt plastic
containers or crack nonborosilicate glassware.
Using and Dispensing Acids
• Always review the Safety Data Sheet (SDS) before
using any hazardous material in the laboratory.
• Students should dispense acids from smaller
bottles to limit spills and fumes.
• Use lab mats and or plastic trays when dispensing
acids to contain acid spills and drips.
• Dispense acids, especially hydrochloric, nitric and
acetic acids, in an operating fume hood.
• During lab, set the acid bottle in a central
dispensing location and have students bring a
graduated cylinder or test tube to the dispensing
area. This will help minimize spills and accidents
and will limit the amount of acid that is brought
back to the lab bench.
• Instruct students to remove from the bottle only
the amount of acid needed for the experiment.
Chemicals are never added back to the reagent
bottle.
• Have acid spill clean-up materials readily available
whenever acids are used.
• Attach a test tube to the reagent bottle to store the
pipet for dispensing an acid.
• Acids are corrosive and will eat through most
fabrics, resulting in small holes in clothing. This
process does not occur instantly, but rather over
several hours, and may not become apparent until
the clothes are washed. Always wear a chemicalresistant
apron or laboratory coat when working
with acids.
SAFETY REFERENCE ACID SAFETY
• If an acid is splashed onto clothing, remove the
clothing immediately before the acid soaks through
the clothing and reacts with the skin. If an acid
splashes onto your skin and clothing, immediately
begin rinsing the affected skin with water (a
safety shower is ideal) and then begin to remove
affected clothing. Modesty must take a back seat
to potential chemical burns that can occur.
• If acid is ingested, the primary goal is to dilute
the acid in the stomach and prevent further injury
caused by vomiting. If the victim is conscious,
immediately
have the victim rinse their mouth
out with water. Have the victim drink one or two
cups of water or milk. Gastric antacids, such as
milk of magnesia or aluminum hydroxide, can
also be given. Do not induce vomiting, do not try
to neutralize the acid with a strong base, and do
not give the victim any sodium bicarbonate or
Always dilute and neutralize acids
before disposal.
any carbonated drinks. Call poison control center
(1-800-222-1222) or hospital emergency room and
follow their directions.
Disposal
• Always dilute and neutralize all acids before
disposal.
• See Flinn Suggested Disposal Methods #24a and
#24b in the Flinn Scientific Catalog/Reference
Manual for detailed disposal procedures and
warnings.
Personal Protection Equipment
and Safety Aids
• Nitrile rubber gloves are acid-resistant and are the
best choice to use when handling concentrated
acids. However, any plastic or vinyl glove will
provide some protection against the occasional
splash, small spill and splatter that may occur when
using or dispensing acids.
• Operating eyewashes must be available in any
classroom or laboratory where acids or acid
solutions are used. An approved eyewash must
treat both eyes and provide clean potable water for
at least 15–20 minutes.
• Chemical splash goggles must be worn anytime
acids or acid solutions are used. Safety glasses are
not adequate protection.
• Good ventilation should be available whenever
hydrochloric, nitric or acetic acid will be used in the
lab.
• Spill control materials (e.g., sand, absorbent and
neutralizer) must be available whenever acids or
acid solutions are used.
First Aid
• Always seek professional medical attention upon
exposure to any hazardous chemical, especially
concentrated acids.
• The best first aid for any chemical exposure to body
tissue or eyes is immediate dilution with water.
• If an acid is splashed in the eyes, use an eyewash
to irrigate the eyes for at least 15–20 minutes. Make
sure the eyelids are held open to properly irrigate
them. Ask the victim to look up, down and sideways
to better reach all parts of the eye.
Always add acid to water…
• If an acid is splashed onto bare skin, rinse with
water for at least 15–20 minutes.
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