Experience has demonstrated the necessity of maintaining a
constant awareness of the hazards of experimental work performed in the study
of chemistry. The best way for a student
to protect himself and his coworkers is to incorporate safety as an integral
part of each task and operation.
You are expected to exercise good judgment and common sense
in preventing hazardous situations. To
help you plan your work safely, this safety handbook has be compiled. Remember that these safe practices are not
hard and fast and that all circumstances are not covered. If under exceptional circumstances good
judgment indicates certain of these practices should not be followed, then make
certain you are not creating a hazard by selecting a different procedure.
I. LABORATORY SAFETY RULES
1. Eye Protection
All students must
wear safety goggles or safety glasses while doing work in the chemistry
laboratory. If you do not have safety
glasses (available in bookstore) do not come to lab. Do not wear contact lens in the lab.
2. Horseplay
Horseplay and practical joking of any kind are strictly
forbidden.
3. Working alone
No one is to perform experimental work in a chemical
laboratory unless a second person is present or nearby.
4. Work authorization
Unauthorized experiments are forbidden. Extra work or original work is encouraged,
but before any experiment is performed in a laboratory, approval must be given
by the instructor in charge.
5. Safety precautions
Before performing any experiment, become familiar with any
safety hazards (flammability, toxicity, etc.) which may be present and take
necessary safety precautions.
6. Reporting
accidents and fires
All accidents resulting in injury, property damage, or fire
must be reported immediately to an instructor.
7. Eating
Preparation, storage, or consumption of food or drink in
work areas is not allowed and should not be practiced because of the danger of
contamination with toxic and poisonous substances. Before handling food, students should
thoroughly wash their hands.
8. Smoking
Smoking is not permitted in the laboratories or
stockrooms. Flammable liquids, vapors,
or gases create a definite fire hazard.
9. Working at night
Except for regularly scheduled night classes, all students
must obtain the instructor’s permission to work in the building after
II. EMERGENCY PROCEDURE
A. In case of accident or illness:
·
Render prompt first aid.
·
Have someone report to an instructor for help.
·
If injury or illness appears to be serious, have someone
call an ambulance.
·
Report all accidents that cause injury, regardless how
minor, immediately to your supervisor.
B. In case of fire:
·
If automatic alarm is not sounded, pull the alarm switch
located in each hall.
·
If fire is small and easily extinguished, use the laboratory
extinguisher at once.
·
If fire is large and difficult to extinguish, have someone
call the fire department at once. Make
sure on one is injured and immediately evacuate the area. Proceed with an orderly evacuation of the
building
·
Immediately report all fires to your instructor.
·
Take all fire extinguishers that have been used to the
storeroom for replacement. Tag such
extinguishers as empty.
·
If your clothing should catch fire, try to stay calm, don’t
run, but quickly get under a shower.
·
Call for help.
·
If the fire alarm sounds, prepare to shut down your
experiment and evacuate the building.
C. First Aid
If any chemical gets into your eyes or mouth, or on your
skin, go quickly to the nearest eye wash, sink or shower and wash with as much
water as possible. If the eye is
involved, hold the eyelids open with your fingers and allow water to run freely over the ball of the eye. It is best to assume that all substances
except pure water are harmful when in contact with any part of the body.
In case of a cut, direct pressure on the cut in usually the
best way to stop bleeding. All cuts,
burns, and other injuries should be reported to the instructor at once.
III. GENERAL LABORATORY
PRACTICES
A. Safety check
1.
Locate all exits from the laboratory and from the
building. Every laboratory has at least
two exits.
2.
Locate the fire extinguisher.
3.
Locate the nearest telephone for use in case of an
emergency.
4.
Locate the safety showers and eye wash fountains.
5.
Locate the power line cut-offs. (multi-breaker
boxes).
6.
Locate the nearest fire alarm switch.
7.
To perform laboratory work safety, it is essential that the
worker include in his experimental design provision for power or water failure
which could cause an accident situation or an unsafe condition to develop. For example, consider the possibility of the
loss of cooling water to a condenser or the loss of power to an expensive
instrument. Plan to meet such an
eventuality.
8.
Operations or experiments are not to be left unattended.
9.
Unsafe conditions and practices cause virtually all
accidents. A person observing an unsafe
act, practice, or situation should call it to the attention of his instructor.
9.
B. Housekeeping (Removal of the Hazard)
The continuous practice of good housekeeping is essential to
the prevention of accidents, fires, and injuries. Students re expected to keep their benches
neat and orderly; a
cluttered laboratory is a dangerous place in which to work.
1.
Keeping benches, tables, hoods, floors, and desks clear of
all material not being used.
2.
Keeping adequate passageway to exits.
3.
Cleaning up spills.
4.
Removing broken glass.
5.
Using proper waste-disposal receptacles.
6.
Keeping all chemical containers clean and properly labeled.
6.
NOTE: Eye wash
fountains are not drinking
fountains or sinks for disposal of chemicals or solutions.
C. Handling Chemicals
Chemicals can be dangerous unless properly handled. Before working with any chemical, know its
properties. Hazardous chemicals include
those which are flammable, toxic, corrosive, and/or reactive. Use of a hood is required in cases where an
undesirable gas is produced.
A most important safety practice is to keep all material
properly labeled. The label should show
the following:
1.
Chemical name and structure.
2.
Date of purchase, preparation, or transfer to present
container.
3.
Brief notation of hazard, if any.
4.
If a solution, concentration and name of person preparing
solution.
Safety
Precautions
1.
Keep reagent container clean.
2.
Use rubber or plastic gloves as necessary.
3.
avoid contact
of chemicals with skin.
4.
Avoid breathing vapors.
5.
Avoid contamination by not returning unused portions of
reagents to stock bottles.
6.
Never taste a chemical.
7.
Do not pipette by mouth
8.
When preparing solutions add concentrated chemicals (never
vice versa).
9.
Keep flammable solvents away from heat and flame.
10. Use care
in transporting chemicals.
11. Use
caution in working with mercury. The
equilibrium concentration of the vapor over liquid mercury at room temperature
is approximately 20 times the threshold toxic limit.
12. Clean up
spills immediately. Use sodium
bicarbonate to neutralize acids and dilute acetic acid to neutralize bases.
13. Never look
directly into a test tube or beaker, or point a test tube toward anyone,
especially when
heating.
14. Before
using a reagent always read the label twice to be certain you have the correct
reagent.
14.
14.
D. Chemical Waste Disposal
1.
Water-soluble wastes may be flushed down the drain with
large amounts of water.
2.
Liquid wastes not miscible with water
must not be poured into the sink.
Consult your laboratory instructor for directions.
3.
Water-insoluble solids should not be poured into the sink.
3.
E. Handling Compressed Gas
Know the
cylinder contents and its properties.
Transport cylinders carefully, using a wheeled cart for large
cylinders. To remove gas through a
regulator, make sure all valves are closed, then open
slowly all valves, starting with the cylinder valve. Make sure all cylinders are securely attached
to a bench or wall.
F. Handling Laboratory Glassware
1.
Always carry glass tubing in a vertical position. Protect hands with towel when cutting tubing.
2.
Lubricate, using water or glycerine,
the surface of glass tubing, and thermometers before inserting into a
stopper. Protect your hands with a
towel. If it is difficult to remove
glass from a stopper, cut off the stopper.
3.
Broken or cracked glassware is unsafe and must be disposed.
4.
Never heat graduated cylinders, bottles, funnels, or watch
glasses over a flame.
G. Fire Prevention
To start a
fire, three components are necessary:
fuel, oxidizing agent, and source of heat for ignition. Many fires can be prevented by keeping fuel
and oxidant away from hot ignition source.
A fire is
extinguished by using the same principles followed in trying to avoid it.
1.
Reduce air supply by smothering—cover the vessel or apply CO2.
2.
Shut off or reduce fuel supply.
3.
Cool the fuel below its ignition temperature.
4.
Lower the concentration of the fuel by diluting with an
inert material.
Types of
Fires:
·
Class A: Burning
wood, paper, cloth, etc.;
extinguish with water, foam, soda-acid, or CO2.
·
Class B: Burning
oils, greases, paints, etc.;
extinguish with foam, CO2, or dry chemical.
·
Class C: Live
electrical equipment;
extinguish with CO2 or dry chemical.
·
Class D: Active
metals, such as sodium, potassium, magnesium etc.; extinguish by smothering
with dry soda ash, or dry chemical extinguisher.
·
H. Teaching
Assistant: Duties and Responsibilities
for Safety:
1.
Teach and enforce safety as an integral part of the course.
2.
See that the students make a careful analysis for safety
before starting an experiment.
3.
See that safety rules are obeyed. Set a good example yourself.
4.
Remain in the laboratory at all times when students are
present.