OMAHA PUBLIC SCHOOLS
SCHOOLHOUSE PLANNING-ENVIRONMENTAL
WASTE DISPOSAL
and LAB SAFETY PRESENTATION
JUNE 1, 2004
Lab waste / Safety
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Handouts include;
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Laboratory Waste Stream
Lab Waste Incompatible Chemicals
Segregate Waste Bottles
Disposal of Non-Hazardous Solid Chemical Waste
Characteristics of Hazardous Waste
MUD Limits
Hazardous Chemicals Prohibited From Drain Disposal
Waste Containers and Labeling Requirements
Peroxide Forming Chemicals
NFPA & HMIS Identification Systems
Lab Safety Websites
The Five Most Common Errors in
Waste Handling
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Improper segregation of waste.
Improper labeling of waste.
Improper storage of waste.
Failure to cap waste bottles
Accumulation of excess waste
Hazardous Waste Generator
Checklist
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Is the container sound?
Is the container compatible with waste?
Are the contents compatible with each other?
Is the Container labeled Hazardous Waste,
Dated and contents by % or volume?
Is the container capped leaving 1” or 10-15%
headspace?
Is the container stored in a safe location?
University of Kentucky 1997
Explosion from the addition of incompatible
chemicals in waste bottle.
University of Kentucky 1997
Explosion from the addition of incompatible
chemicals in waste bottle.
University of Kentucky 1997
Explosion from the addition of incompatible
chemicals in waste bottle.
PROFESSOR GLICKMAN, THE LAB PRACTICAL JOKER,
DEFTLY PLACES A DROP OF HYDROCHLORIC ACID
ON THE BACK OF PROFESSOR BIGHAM’S NECK.
GARY LARSON—THE FAR SIDE
Most common lab accidents
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Nature/Causes:
Accidents of various nature were reported. Over 90% of the cases
under this category were mere accidental breakage of glassware or
damage of equipment.
Students were hurt when they knocked on floor, stools, benches, or
cupboards.
Tasting of chemicals (e.g. copper (II) sulfate) by students.
Safety Precautions:
All glass items should be handled with care.
Certain laboratory safety rules are fundamental and teachers need
to stress their importance continually to students.
A reasonably good control of class discipline should be maintained
during practical lessons.
Students should not be allowed to engage in horseplay inside the
laboratory and they should be trained to follow instructions given by
the teacher.
Eye Accidents
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Causes/Nature:
Chemical liquids or solids which splashed onto the eyes, giving rise to slight irritation
or discomfort.
Students unintentionally rubbed their eyes with hands contaminated with chemicals.
The chemicals commonly involved were copper (II) sulfate, dilute acids and alkalis.
Students looked at bright light through a magnifying glass.
Safety Precautions:
Eye injuries can be very damaging and hence for accidents involving the eyes,
medical advice should be sought immediately and the cases reported to Risk
Management as soon as possible.
Each laboratory should be equipped with enough safety goggles for use by every
student. Other protective equipment like safety screens should be used where
appropriate to safeguard against injuries.
Teachers should ensure that safety goggles are worn by all students whenever there
is any risk of eye injury. This will include activities involving heating chemicals,
handling acids, alkalis and other corrosive chemicals, working with glass apparatus
under pressure, carrying out potentially violent or exothermic reactions.
Whenever safety goggles are required, they should be continually worn by all until
everyone has finished the activity.
Students should also be asked to wear safety goggles even when observing science
experiments demonstrated by the teacher and washing up laboratory apparatus
Chemical Spills
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Nature/Causes:
Small-scale spillage of chemicals during transfer.
Spillage of mercury from broken mercury thermometers or from its
container.
Incorrect techniques exercised by students in using apparatus such
as separating funnel.
Safety Precautions:
Spilled chemicals should be contained and removed following
proper procedures. Detailed handling methods for chemical spillage
can be found in the Handbook on Safety in Science Laboratories.
Teflon coated mercury thermometers may be used to reduce the
problems of durability and spill cleanup. In the event of breakage the
Teflon coating can contain the mercury
Chemicals on Skin
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Nature/Causes:
Spillage of chemicals during transfer or heating of chemical liquids, washing up of
apparatus containing chemical mixtures, opening the container of chemical or
breakage of glass containers.
Students' mischievous behavior of pouring chemicals to others.
Concentrated sulfuric acid, phenol and sodium hydroxide were the most common
harmful chemicals involved.
Safety Precautions:
Chemicals should always be handled with great care.
The correct ways of handling chemicals should be used, e.g. avoid direct skin contact
when transferring chemicals.
Protective gloves should be worn when highly corrosive chemicals are handled.
Proper laboratory spatula, instead of narrow stem plastic teaspoon, should be used
for handling chemical solids.
All chemicals should never be tasted.
Wash hands after handling chemicals and before leaving the laboratory.
Use the minimum amount and lowest concentration of chemicals in doing
experiments, and use safer alternatives to replace hazardous chemicals or
dangerous procedures whenever possible.
To reduce the possibility of a liquid spurting from the test tube while heating, fill no
more than 1/3 of the test tube with the liquid and heat gently while shaking. Boiling
tubes are preferable to test tubes for boiling liquids. Vigorous boiling can normally be
prevented by adding anti-bumping granules. The mouths of test tubes should never
be pointed towards oneself or others.
Heat Burns / Scalds
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Nature/Causes:
Carelessness in handling hot objects (e.g. tripods, glassware, metal rods/plates,
crucibles or combustion spoons), hot liquids, Bunsen flame or lighted matches.
Safety Precautions:
Do not touch or hold hot objects with bare hands.
Crucible tongs or heat-resistant gloves should be used when picking up hot objects.
Place them on a heat-resistant mat, not directly on the bench, for cooling.
Burners, wire gauzes and tripods remain hot for some time after use. They should
also be handled with care.
Burner tubing should be secured to gas taps and burners by hose clips. They should
also be regularly inspected for defects and replaced at least every three years.
Care should be exercised to ensure that the gas tap to be turned on is the one
connected to the burner. Turn off Bunsen burners that will not be used for some time.
Arms or any parts of the body should not be stretched over lighted burners.
Long hair should be tied up and loose-fit clothing avoided.
Do not apply ointments or any other chemicals to the injured area of heat burn.
CUTS
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Nature/Causes:
Small cuts caused by broken glass apparatus (e.g. test tubes, or
glass tubing), tools (e.g. dissecting instruments, cork borer or cutter)
or sharp edges.
Safety Precautions:
Students should be taught the correct ways of using sharp
instruments (e.g. razor blades, scalpels) with care and not to play
with them.
Unwanted razor blades and mounting needles should be properly
wrapped up before disposal.
Glassware showing signs of cracking or those with broken edges
should not be used for experiments.
The correct way of handling glass apparatus (e.g. fitting a pipette
filler to a pipette) should be taught to students.
Broken pieces of glass should be disposed of properly in a metal or
plastic container assigned for such purpose and never into a general
rubbish container.
SUBSTANCES CATCHING FIRE
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Nature/Causes:
Accidental ignition of flammable liquids (e.g. ethanol or methanol).
Ignition of gas coming out from defective burner tubing or from
opened gas tap not connected to Bunsen burner.
¾ Ignition of blackout curtain by focused sunlight from optical
instrument.
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Safety Precautions:
For flammable chemicals, heating should always be done using a
hot water or oil bath with no naked flame nearby.
¾ The quantity of flammable chemicals used by students during
experiments should be kept to a minimum.
¾ In testing for flammability of liquids, care should be taken not to add
additional liquid to the burning fraction
HMIS
NFPA
What’s wrong with this picture?
Position the hood sash as low as
possible.
PLEASE REMEMBER
¾ LABEL ALL CHEMICAL WASTE
¾ INCOMPATIBLE
CHEMICAL
AWARENESS
¾ PRACTICING SAFE TECHNIQUES
BENEFITS YOU AND OTHERS
¾ University of Kentucky pictures used with
permission granted by Rob Toreki, Safety
Emporium.